The presentation will cover breakthroughs in detector technology in accelerator based and non-accelerator based particle physics experiments and facilities.
I review recent developments in the global QCD analysis by the CTEQ-TEA group that follows the public release of the new CT18 NNLO parton distributions last year [arXiv:1912.10053]. The role of LHC experiments at 7, 8, and 13 TeV in constraining the CT PDFs is discussed. Theoretical and methodological advancements aimed at obtaining reliable central PDFs and their uncertainties are reviewed,...
Testing the couplings of the Higgs boson to leptons is important to understand the origin of lepton masses. This talk presents measurements of Higgs boson production in decays to two tau leptons or two muons based on pp collision data collected at 13 TeV.
LHCb is a fully instrumented spectrometer covering the forward rapidity region at the LHC, and provides unique access to the small x region inside the nucleus. This talk will present a selection of recent results from the LHCb heavy ion program, including data on charged hadrons, open charm and charmonia production in pPb collisions, and J/psi production in peripheral PbPb collisions....
Threshold photoproduction of charmonium at JLab and EIC can be used to extract the distribution of mass inside the proton by using the scale anomaly of QCD and the multipole expansion. Theoretical analysis of this problem will be presented and confronted with the first experimental data from JLab.
The suppression of $J/\psi$ production caused by the color-screening effect in heavy-ion collisions is considered as an evidence of the creation of quark-gluon plasma. To interpret the observed suppression in heavy-ion collisions, a good understanding of its production mechanism in p+p collisions is needed. However, the production of $J/\psi$ in hadronic collisions remains not fully understood...
The CMS experiment at LHC has performed the first measurement of the CP structure of the Yukawa coupling between the Higgs boson and tau leptons. The measurement is based on data collected in proton-proton collisions at sqrt(s) = 13 TeV during 2016-18, corresponding to an integrated luminosity of 137 fb^-1. The analysis utilizes the angular correlation between the decay planes of tau leptons...
In this talk we present the analysis of prompt photon production at the LHC with the kT-factorization approach. We consider two leading partonic channels, qg->q\gamma and gg*->q\bar{q}\gamma and three theoretical schemes known under the acronyms KMR, GBW, CCFM. We find sensitivity of the calculated prompt photon transverse momentum distribution to the gluon transverse momentum distribution....
The experimental observation of strikingly large transverse single-spin asymmetries (TSSAs) revealed that there were significant spin-momentum correlations present in hadronic collisions, both within nucleons and the process of hadronization. TSSA measurements have allowed for the development of both transverse momentum dependent and collinear twist-3 descriptions of these nonperturbative...
We present recent updates from the CTEQ-Jefferson Lab (CJ) global analysis of parton distribution functions with a new set of electroweak measurements. Electroweak measurements in proton collisions provide unique access to quark flavor separation and strangeness in the proton. In particular, recent W and Z boson measurements from the STAR experiment at RHIC are included which provide...
The Electron-Ion Collider (EIC) is a new, innovative, large-scale particle accelerator to be built at Brookhaven National Lab in the USA over the next 10 years. It will collide beams of polarized electrons with polarized beams of light ions, or with heavy ions, at high luminosity. The goal is to study the fundamental structure of nucleons and nuclei, and the theory of Quantum Chromodynamics...
The CP structure of the Higgs boson in its coupling to the particles of the Standard Model is amongst the most important Higgs boson properties which have not yet been constrained with high precision. In this study, all relevant inclusive and differential Higgs boson measurements from the ATLAS and CMS experiments are used to constrain the CP-nature of the top-Yukawa interaction. The model...
We present, the results of a phenomenology analysis at Next-to-Leading accuracy for the Mueller-Tang jet process, where two jets separated by a large rapidity interval and no other radiation are observed. This process is of high interest, as one might be able to investigate Balitsky-Fadin-Kuraev-Lipatov (BFKL) dynamics which emerges in the high-energy limit of quantum chromodynamics...
We study inclusive $J/\psi$ photoproduction at NLO at large $P_T$ at HERA and the EIC. Our computation includes NLO QCD leading P_T corrections, QED contributions via an off-shell photon as well as those from $J/\psi$+charm channels. For the latter, we employ the variable-flavour-number scheme. Our results are found to agree with the latest HERA data by H1 and provide, for the first time, a...
Understanding the transverse spin and momentum structure of the proton is of large interest to the nuclear physics community and it is one of the main goals of the spin physics program at the Relativistic Heavy Ion Collider (RHIC). Transverse single spin asymmetry measurements for charged particles produced in proton proton collisions provide keen insight into initial and final state...
We present a new release of the NNPDF family of global analyses of parton distribution functions: NNPDF4.0. It includes a wealth of new experimental data from HERA and the LHC, from dijet cross-sections to single-top and top-quark pair differential distributions. The NNPDF4.0 methodology benefits from improved machine learning algorithms, in particular automated hyperparameter optimisation and...
The realisation of the LHeC and the FCC-eh at CERN require the development of the energy recovering technique in multipass mode and for large currents ${\mathcal O}(10)$ mA in the SRF cavities. For this purpose, a technology development facility, PERLE, is under design to be built at IJCLab Orsay, which has the key LHeC ERL parameters, in terms of configuration, source, current, frequency and...
Recent results from the ATLAS experiment on charmonium production will be presented. The measurement of the associated production of the J/psi meson and a photon, including an estimation of the transverse-momentum-dependent distribution function of linearly polarized gluons in an unpolarized proton, will be discussed. The measurement of J/psi and psi(2S) differential cross sections at large...
Proton at high energy is a hugely complex many-body quantum system where gluons are the dominant degrees of freedom. The information of the three-dimensional structure of the proton is encoded in the transverse Momentum Dependent Parton distribution function (TMDs). Transverse Momentum Dependent Parton distribution functions (TMDs) are among the key subjects to be fully investigated at current...
This paper presents an experimental study of proton-proton collision events where the two leading jets are separated by a large pseudorapidity interval devoid of particle activity, referred to as jet-gap-jet events. The pseudorapidity gap is expected from hard color-singlet exchange. The analysis is based on data collected by the CMS and TOTEM experiments during a low luminosity,...
With the pp collision dataset collected at 13 TeV, detailed measurements of Higgs boson properties can be performed. This talk presents measurements of Higgs boson properties using Higgs boson decays to two photons, two Z bosons, or two W bosons, including production mode cross sections and simplified template cross sections.
We present predictions and projections for hadron-in-jet measurements and electron-jet azimuthal correlations at the future Electron-Ion Collider. These observables directly probe the quark transversity and Sivers parton distributions, the Collins fragmentation functions, and TMD evolution. This jet-based approach will allow us to avoid the convolution of TMD parton distributions and...
Transverse momentum dependent parton distribution functions (TMDs) are extensions of the well- known collinear PDFs. They contain, apart from the usual x- and scale dependence, also information on the intrinsic transverse momentum carried by the parton, and on the spin correlations.
Experimentally, not so much is known about gluon TMDs, since they are subleading with respect to their quark...
We present recent results on the analysis of Higgs to WW decays and the corresponding constraints on the Higgs couplings. Focus is concentrated on the recent measurements exploiting the full Run 2 statistics. Recent constraints on new physics models derived from high mass searches in the WW channel are also presented.
Inclusive measurements of forward back-to-back dijets/dihadrons in deeply inelastic scattering (DIS) present a promising channel to access signatures of gluon saturation inside nuclear matter at the future Electron-Ion Collider (EIC). Most phenomenological studies employ the transverse momentum dependent (TMD) factorization framework; however, there are important kinematic (perturbative power)...
We study the Sivers azimuthal asymmetry, and the role of the gluon Sivers function (GSF), in inelastic $J/\psi$ leptoproduction, $l\,p^\uparrow \to l'+ J/\psi+ X$, at small-to-moderate transverse momentum. To this end, we adopt the color-gauge invariant generalized parton model and the NRQCD framework for quarkonium formation. We compare our estimates for the unpolarized cross-section with...
We present the new MSHT2020 set of parton distribution functions (PDFs) of the proton, determined from global analyses of the available hard scattering data. The PDFs are obtained using the same basic framework as MMHT2014, but supersede these. The parameterisation is now adapted and extended and we include a large number of new data sets: from the final HERA combined data on total and heavy...
The SPD (Spin Physics Detector) facility is meant to be a universal 4π detector at the new collider complex NICA at the Joint Institute for Nuclear Research (JINR, Russia). The main goal of the experiment is to study the polarized gluon structure of proton and deuteron in the production of charmonium, open charm and direct photons. At its initial stage, SPD will also focus on various...
The Belle II experiment at the SuperKEKB energy-asymmetric $e^+ e^-$ collider is an upgrade of the B factory facility at KEK in Tsukuba, Japan. The experiment began operation in 2019 and aims to record a factor of 50 times more data than its predecessor. Belle II is uniquely capable of studying the so-called "XYZ" particles: heavy exotic hadrons consisting of more than three quarks. First...
We present results with soft-gluon resummation for the associated production of a single top quark and a Higgs boson. We present analytical results for the higher-order soft-gluon corrections and numerical results for the total cross section and top-quark transverse momentum and rapidity distributions at LHC energies.
At large values of $x$ the parton distribution functions (PDFs) of the proton are poorly constrained and there are considerable variations between different global fits. Data at such high $x$ have already been published by the ZEUS Collaboration, but not yet used in PDF extractions. A technique for comparing predictions based on different PDF sets to the observed number of events in the ZEUS...
The LHeC and the FCC-eh offer fascinating, unique possibilities for discovering BSM physics in DIS, both due to their large centre-of-mass energies and high luminosities. In this talk we will review most recent studies as presented in the 2020 LHeC Conceptual Design Report update [1]. We will show the prospects for observing extensions of the Higgs sectors both with charged and neutral...
The most precise measurements of Higgs boson cross sections, using the framework of simplified template cross sections, are obtained from a combination of the measurements performed in the different Higgs boson decay channels. This talk presents the combined measurements, as well as their interpretations.
A framework to study gluon saturation in QCD using trijet processes is presented.
The so-called small-x Improved Transverse Momentum Dependent factorization (ITMD) was originally formulated for the dijet final states in hadron collisions. I present results for a multiparton extension, in particular for trijets both for proton-proton and proton-lead collisions at center of mass energy 5.02...
We study exclusive quarkonium production in the dipole picture at next-to-leading order (NLO) accuracy, using the non-relativistic expansion for the quarkonium wavefunction. This process offers one of the best ways to obtain information about gluon distributions at small x, in ultraperipheral heavy ion collisions and in deep inelastic scattering. The quarkonium light cone wave functions needed...
Recent results from the ATLAS experiment on exotic heavy hadrons will be presented. Studies of the Pentaquarks with hidden charm in the Lambda_b decays in proton-proton collisions at 7 - 8 TeV will be discussed. New results on the heavy tetraquarks in the Run 2 data at 13 TeV will also be reported.
A comprehensive set of azimuthal single-spin and double-spin asymmetries in semi-inclusive leptoproduction of pions, charged kaons, protons, and antiprotons from transversely polarized protons is presented. These asymmetries include the previously published \hermes results on Collins and Sivers asymmetries, the analysis of which has been extended to include protons and antiprotons and also to...
We present a new global QCD analysis of inclusive DIS data, using a Monte Carlo approach to extract the spin-averaged PDFs. We focus on the high-$x$, low-$W$ region, where effects from power corrections, such as target mass corrections (TMCs) and higher twists, are important. We focus in particular on the quantification of the nuclear corrections, including Fermi motion, binding and nucleon...
The universality of the couplings of the different generations of leptons to the electroweak gauge bosons is at the core of the Standard Model of particle physics. In this contribution, a measurement of the ratio of the rate of decay of W bosons to τ-leptons and muons, R(τ/μ)=B(W→τντ)/B(W→μνμ), is presented, that constitutes an important test of this axiom. The measurement is based on a novel...
The sPHENIX detector currently under construction at Brookhaven National Laboratory's Relativistic Heavy Ion Collider (RHIC) is designed to significantly advance studies of the microscopic nature of the Quark Gluon Plasma. With a multi-year physics program beginning in 2023, sPHENIX employs state-of-the art detector technologies and will fully exploit the highest planned RHIC luminosities. ...
Measurements of the differential cross sections of Z + jets and γ + jets production, and their ratio, are presented as a function of the boson transverse momentum. Measure- ments are also presented of the angular distribution between the Z boson direction and a jet in events where the Z boson is emitted collinear with a jet. The analysis is based on a data sample of proton-proton collisions at...
As data become more precise, estimating theoretical uncertainties in global PDF determinations is likely to become increasingly necessary to obtain correspondingly precise PDFs. Here we present a next generation of global proton PDFs (NNPDF4.0) that include theoretical uncertainties due to the use of heavy nuclear and deuteron data in the fit. We estimate these uncertainties by comparing...
We apply the formalism developed earlier $[1,2]$ for studying the small-$x$ asymptotics of transverse momentum dependent parton distribution functions (TMDs) to construct the small-$x$ asymptotics of the quark Sivers function. We explicitly construct the transversely polarized, fundamental "Wilson line" operator to sub-sub-eikonal order. We then express the Sivers function in terms of dipole...
We discuss the production mechanism of a new state, a fully charm tetraquark, discovered recently by the LHCb at M = 6.9 GeV in the $J/\psi J/\psi$ channel. Both single parton scattering (SPS) and double parton scattering (DPS) mechanisms are considered. We calculate the distribution in the invariant mass of the four-quark system $M_{4c}$ for SPS and DPS production of $c c \bar c \bar...
The exploration of the transverse spin structure of the nucleon by measuring the transverse-spin-dependent azimuthal asymmetries in Drell-Yan process is one of the main topics of the phase-II research programme of the COMPASS experiment (CERN, SPS-M2 beamline).
In 2015 and 2018 the experiment performed Drell-Yan measurements using a 190 GeV $\pi^-$ beam interacting with a transversely...
The description of the Drell-Yan (DY) transverse momentum spectrum requires matching of fixed order QCD calculations with soft gluon resummation up to all orders in the QCD coupling. It has been noticed in the literature that a consistent description of DY data in a wide kinematic regime from fixed-target to LHC energies is problematic. In this talk the predictions for transverse momentum...
Within the Color Glass Condensate effective theory or other related frameworks, the theoretical description of low-x (or high-energy) QCD processes sensitive to the nonlinear gluon saturation physics relies on two main pillars.
The first one is the semiclassical approach: due to the high density of low x gluons in an incoming proton or nucleus target, scattering processes off that target...
Exotic hadrons, which are composed of more than three valence quarks, can provide new insights into the internal structure and dynamics of hadrons, thus improving our knowledge of the non-perturbative regime of QCD. The data collected by the LHCb experiment provides unique opportunities for precise measurement of properties of established exotic hadrons and search for new ones. This talk...
We perform the global analysis of polarized Semi-Inclusive Deep Inelastic Scattering (SIDIS), pion-induced polarized Drell-Yan (DY), and W/Z boson production data and extract the Sivers function for u, d, s and for sea-quarks. We use the framework of transverse momentum dependent factorization at N3LO accuracy. The Qiu-Sterman function is determined in a model-independent way from the...
Precision measurements of the production cross-sections of W/Z boson at LHC provide important tests of perturbative QCD and information about the parton distribution functions for quarks within the proton. We present measurements of fiducial integrated and differential cross sections for inclusive W+, W− and Z boson production using data collected by the ATLAS experiment at various...
We calculate the inclusive quark-photon production in high energy proton-nucleus collisions using a new formalism which includes the dynamics of gluon saturation at small $x$ as well as large x gluons of the target. We show how this unified formalism can be applied to di-jet production in DIS at all Bjorken x.
In this talk, we present a thorough analysis of $\eta_c(1S, 2S)$ and $\chi_{c0},\chi_{b0}$ quarkonia hadroproduction in $k_T$-factorisation in the framework of the light-front potential approach for the quarkonium wave function.
The off-shell matrix elements for the $g^{*}g^{*}\to\eta_c, \chi_{c0}$
vertices are derived in terms of the quarkonium light-front wave function.
We discuss the...
We report on our progress in updating our global analysis of nuclear PDFs. In particular, we will discuss the inclusion of double differential 5TeV dijet and D-meson measurements, as well as 8TeV electroweak data from LHC p-Pb collisions. The new analysis will also involve recent JLab data for deeply-inelastic scattering. As a novel aspect within our approach, we now intend to also chart the...
The Bayesian reweighting procedure is applied for the first time to a transverse momentum dependent distribution, the quark Sivers function extracted from Semi-Inclusive DIS (SIDIS) data. By exploting the recent published single spin asymmetry data for the inclusive jet production in $p^\uparrow p$ collisions from the STAR collaboration at RHIC, we show how such a procedure allows to...
The LHeC and the FCC-eh will open a new realm in our understanding of nuclear structure and the dynamics in processes involving nuclei, in an unexplored kinematic domain. In this talk we will review the most recent studies as shown in the update of the 2012 CDR [1]. We will discuss the determination of nuclear parton densities in the framework of global fits and for a single nucleus. Then we...
Quasi parton distribution functions (PDFs) are related to the matrix elements of bilocal operators with space-like separation. The possibility to calculate these objects on the lattice has attracted much attention in the QCD community. I will present the behavior of quark and gluon quasi-PDFs at low-x.
The large data sample accumulated by the Belle experiment at the KEKB asymmetric-energy e^{+}e^{-} collider provides a unique opportunity to perform studies related to hadron spectroscopy utilising various production mechanisms. We report on radiative decays of excited Xi_c baryons, study of Xi_c → Xi_0 K+ K0, branching fraction measurement of Lambda_c^+, determination of the spin and parity...
Pseudo-data with simulated experimental errors can be generated to train an ensemble of Artificial Neural Networks (ANN) implemented on a regression to extract Transverse Momentum-dependent Distributions (TMDs). A preliminary analysis will be presented on the reliability in extraction of the Sivers function imposed in the pseudo-data given the bounds on the experimental errors, data sparsity,...
The recent exclusive backward-angle electroproduction of omega from Jefferson Lab Hall C electron-proton fixed-target scattering experiments above the resonance region, published in the PRL, hints on a new domain of applicability of QCD factorization in a unique u-channel kinematics regime. Thanks this pioneering effort, the interests of studying nucleon structure through u-channel meson...
Understanding the relation between QCD evolution in the Bjorken limit and the Regge limit is crucial to achieve a complete and smooth picture of proton and nuclear structure. The hope in the small x regime (where gluon density is expected to reach saturation and the naif partonic breaks down), was that by computing higher order corrections to small x evolution (BK equations) one would capture...
Thanks to the large amount of data that is being and will be collected at Run-III and High Luminosity (HL) stage, precision measurements at the LHC are reaching an unprecedented level of statistical accuracy, whilst PDF uncertainties prevail. We study the impact of future measurements of lepton-charge and forward-backward asymmetries on PDF determination. The numerical results have been...
Heavy quarkonium production provides valuable opportunities for exploring fundamental QCD dynamics with multiple scales. Thus far, NRQCD factorization has been successful in describing many features of the data. Despite many theoretical efforts at NLO accuracy, however, there are still unresolved issues, including the lack of a full understanding of quarkonium polarization at high $p_T$. One...
We perform explorative analyses of the 3D gluon content of the proton via a study of unpolarized and polarized gluon TMDs at twist-2, calculated in a spectator model for the parent nucleon. Our approach embodies a flexible parametrization for the spectator-mass function, suited to describe both moderate and small-$x$ effects. All these studies can serve as a useful guidance in the...
W and Z boson production and Neutrino deep inelastic scattering (DIS) data are the two most important data sets for constraining the strange quark parton distribution function (PDF) and for flavor decomposition in PDF extractions in general. We extend the nCTEQ15 nuclear PDFs (nPDFs) by adding the recent W and Z production data from LHC in a nCTEQ framework-based global nPDF fit. We identify...
High-$p_T$, multi-lepton events remain one of the most sensitive probes of new physics at the LHC. Despite this, multi-weak boson and top quark-associated production channels remain leading Standard Model backgrounds for these signatures. We present a new class of jet vetoes, one that is defined on an event-by-event basis, that precisely targets these so-called irreducible backgrounds and can...
The analysis of single transverse-spin asymmetries (SSAs) gives us tremendous insight into the internal structure of hadrons. For example, the Sivers and Collins effects in semi-inclusive deep-inelastic scattering (SIDIS), Sivers effect in Drell-Yan, and the Collins effect in electron-positron annihilation have been widely investigated over many years in order to perform 3D momentum-space...
Gluon parton distribution functions (PDF) in protons and nuclei are known
to be difficult to determine with fits of deep inelastic scattering (DIS)
and Drell-Yan (DY) data alone. The nCTEQ15 analysis of nuclear PDFs
therefore resorted also to inclusive neutral pion production data from
RHIC. In this talk, we present a new global analysis of nuclear PDFs based
on a much larger set of...
In hadronic collisions, beauty quarks are produced in hard-scattering processes with large momentum transfer. The production of hadrons containing beauty quarks provides a very important test of perturbative QCD calculations in pp collisions. The measurement of the production of beauty-strange mesons relative to that of beauty hadrons without strange-quark content is useful to study the...
The CLAS12 detector at Jefferson Lab produced the first results in SIDIS and DI-HADRON reactions. Making use of the CEBAF high energy (up to 11 GeV) and highly longitudinal polartized (up to 90%) electron beam will cover unexplored territories in electron-scattering physics. Exclusive reactions on nuclons and nuclei will be measured with high precision in high luminosity (up to 10e35 cm-2s-1)...
Droplets of quark-gluon plasma produced in heavy-ion collisions rapidly evolve expanding and cooling. During considerable part of this dynamics the system can be described within relativistic hydrodynamics. Recently, there were some attempts to include effects of the medium motion to the jet energy loss and jet modification calculations in a variety of models. Here we will present the first...
We present an update of the measurements of the azimuthal decorrelation angle between the leading jet and scattered lepton in deep inelastic scattering, with the ZEUS detector at HERA. The studied data was collected in the HERA II data-taking period and corresponds to an integrated luminosity of ~ 330 pb$^{-1}$. Azimuthal angular decorrelation has been proposed to study the $Q^2$ dependence of...
We use the nCTEQ analysis framework to investigate nuclear Parton Distribution Functions (nPDFs) in the region of large x and intermediate-to-low Q, with special attention to recent JLab Deep Inelastic Scattering data on nuclear targets. This data lies in a region which is often excluded by W and Q cuts in global nPDF analyses. As we relax these cuts, we enter a new kinematic region, which...
Many theories beyond the Standard Model predict additional Higgs bosons or other resonances, either at lower or higher masses than the observed Higgs boson near a mass of 125 GeV. This talk presents searches for such new states in leptonic or photonic final states using the full LHC Run 2 dataset recorded with the ATLAS detector.
The transversity distribution function, $h^{q}_{1}(x)$, a leading twist parton distribution function, is a fundamental component of the spin structure of the nucleon. $h^{q}_{1}(x)$ describes the distributions of transversely polarized quarks inside a transversely polarized nucleon, where x is the longitudinal8momentum fraction of the proton carried by quark q. It is loosely constrained by...
SoLID spectrometer was proposed to fully exploit the potential of JLab 12 GeV energy upgrade. It is a large acceptance detector which can handle very high luminosity. An overview of the rich physics program will be given, which includes number of planned measurements: a multi-dimensional mapping of semi-inclusive DIS asymmetries for tomography of the nucleon in momentum space in the high-x...
We present the results that are necessary in the ongoing lattice calculations of the gluon parton distribution functions (PDFs) within the pseudo-PDF approach. We give a classification of possible two-gluon correlator functions and identify those that contain the invariant amplitude determining the gluon PDF in the light-cone $z^2\to0$ limit. One-loop calculations have been performed in the...
Light meson measurements in high-energy proton-nucleus collisions provide a probe to study the physics of strongly interacting matter and the quark-gluon plasma. In particular, measuring the nuclear modification factor, where the particle production in p-A is compared to a baseline proton-proton reference which is scaled to account for nuclear geometry, provides important insight to the...
Lepton flavor violation (LFV) constitutes a clear signature of New Physics, and has been searched for in many experiments. We present recent results on LFV searches from the Belle experiment. The results include a search for B → K(*) l l', B → tau l, tau → p l l', tau → l gamma decays. We also cover the study on the lepton flavor universality. The results are based on the full data sample...
We present a constrained analysis of the valence transversity Parton Distribution Functions from dihadron production in semi-inclusive DIS. While usual extractions of the transversity distributions rely explicitly on the fulfilment of the Soffer bounds, our analysis releases that restriction to implement further constraints through the Lagrange multipliers method. The results are...
Two-particle azimuthal correlations have been measured in neutral current deep inelastic ep scattering with virtuality $Q^2> 5$ GeV$^2$ at a centre-of-mass energy $\sqrt{𝑠}= 318$ GeV recorded with the ZEUS detector at HERA. The correlations of charged particles have been measured in the range of laboratory pseudorapidity $−1.5 < \eta < 2.0$ and transverse momentum $0.1 < p_T< 5.0$ GeV and...
The goal of LHCspin is to develop, in the next few years, innovative solutions and cutting-edge technologies to access spin physics in high-energy polarized fixed-target collisions, by exploring a unique kinematic regime given by the LHC beam and by exploiting new probes.
This ambitious task poses its basis on the recent installation of SMOG2, the unpolarized gas target in front of the LHCb...
We propose a new method for the extraction of transversity distributions from Semi-Inclusive Deep Inelastic Scattering (SIDIS) data. The $u$-quark and $d$-quark transversity distributions are usually extracted from spin asymmetry data in the SIDIS processes, where it has to be coupled with a chiral odd-partner, typically the Collins or the di-hadron fragmentation function. Motivated by a...
We present a comprehensive analysis of the potential sensitivity of the Electron-Ion Collider (EIC) to charged lepton flavor violation (CLFV) in the channel $ep\to \tau X$, within the model-independent framework of the Standard Model Effective Field Theory (SMEFT). We compute the relevant cross sections to leading order and
perform simulations of signal and SM background events in...
The ridge phenomenon found in high multiplicity pp and pPb collisions is one of the most important observations at the LHC. In such small systems, final state explanations become challenging. We study particle correlations in the Color Glass Condensate, which offers a weak coupling but non perturbative framework to study how correlations in the wave function of the incoming hadrons reflect on...
A. SHABETAI (for the ALICE Collaboration)
The measurement of jet production and structure observables in pp collisions provides significant tests of perturbative QCD. Jet measurements in proton-lead collisions enable study of cold nuclear matter effects. Jets are generated in the early stages of ultra-relativistic heavy-ion collisions and provide unique channels for probing the quark-gluon...
Investigations of coherent production background and eA collision geometry using forward particles at the EIC
Wan Chang
Institute of Particle Physics, Central China Normal University, Wuhan 430079, China
and Department of Physics, Brookhaven National Laboratory, Upton, NY 11973, USA
changwan@mails.ccnu.edu.cn
The Electron-Ion Collider (EIC) is a next generation accelerator which will...
The finding of long rapidity range azimuthal correlations in small collision systems, pp and pA, at the LHC poses a crucial challenge for our understanding of hadronic and nuclear collisions at the highest available energies. In such small collisions systems the final state explanations standardly accepted in heavy ion collisions face conceptual problems and initial state alternatives have...
We present results on the nucleon valence quark distribution extracted from Lattice QCD simulations, using a gauge ensemble of $N_f=2+1$ Wilson-Clover fermions with a pion mass of $m_\pi = 350$ MeV and lattice spacing of $a=0.091$ fm. We obtain reduced Ioffe Time Distributions (rITDs) by computing appropriate matrix elements on the lattice, and elaborate on the extraction of the desired quark...
Using the unification of chiral SU(3) model and QCD sum rules, we deduce the in-medium properties of $K^\pm_1$ meson. Within chiral SU(3) model, medium modified gluon and quark condensates are evaluated through their interactions with the scalar fields ($\sigma$, $\zeta$, $\delta$ and $\chi$). These condensates are further used as input in the Borel transformed equations of QCD sum rules to...
Leptoquarks (LQ) are predicted by many new physics theories to describe the similarities between the lepton and quark sectors of the Standard Model and offer an attractive potential explanation for the lepton flavour anomalies observed at LHCb and flavour factories. The ATLAS experiment has a broad program of direct searches for leptoquarks, coupling to the first-, second- or third-generation...
Quasi-PDF approach, proposed by Ji in 2013, has made it possible to directly extract light-cone PDFs from lattice QCD. This approach relies on the extraction of matrix elements of space-like operators for fast-moving hadrons. Quasi-PDFs can be related to the light-cone PDFs through a perturbatively calculable matching coefficient. We explore the formalism of matching, for the very first time,...
Color charge correlations in the proton at moderately small x are
extracted from its light-cone wave function. ${\cal O}(g^2)$ corrections to the
leading order correlations due to perturbative emission of a gluon,
which is not required to be soft, have been accounted for. This
analysis provides initial conditions for Balitsky-Kovchegov
high-energy evolution of the dipole scattering...
Studies on the production of light- and heavy-flavour baryons are of prominent importance to characterise the partonic phase created in ultrarelativistic heavy-ion collisions and to investigate hadronization mechanisms at the LHC, in particular through the study of the evolution of the baryon-over-meson production ratio as a function of the transverse momentum. Measurements performed in pp and...
In large-momentum effective theory, renormalization of
the Euclidean operators in lattice regularization is a challenge due to the linear divergences in the self-energy of Wilson lines.
Based on the Lattice QCD matrix elements of the quasi-PDF operator at $a$= 0.03fm $\sim$ 0.12 fm with clover and overlap valence quarks on staggered and domain-wall sea, we design a strategy to disentangle...
Twist-3 PDFs contain important information that characterizes nucleon's structure. In this talk, we show our lattice exploration of the twist-3 PDFs g_T(x) and h_L(x). We use the quasi-distribution approach to connect the lattice-extracted matrix elements, renormalized in the RI/MOM scheme, to light-cone distributions, applying the matching procedure that we developed in parallel. We also...
Jets are algorithmic proxies of hard scattered partons, i.e. quarks/gluons, in high energy collisions. Current jet measurements utilize algorithms that cluster objects, either particles from an event generator or charged tracks/calorimeter towers in experiments, iteratively depending on the distance between objects and a momentum threshold. These clustering algorithms contain additional...
Through the 21st and 22nd International Workshop on Deep Inelastic Scattering, a possibility of the non-perturbative contribution for the non-zero transverse single spin asymmetry of $\pi^0$ ($2 < \eta < 4$) was brought up. Bigger asymmetry was observed in more isolated final state which was connected with the non-perturbative event topology. Since the non-perturbative contribution has been...
A multi-TeV muon collider is a discovery machine and an invaluable tool for many precision measurements such as the shape of the Higgs boson potential. The update of the European Strategy for Particle Physics recognized the unique opportunity of a muon collider to reach the energy frontier, despite the challenges to produce intense cooled muon beams. A 3 TeV and a 10+ TeV collider option is...
The Precision Proton Spectrometer (PPS) started operating in 2016 and has collected more than 110 fb−1 of data over the course of the LHC Run 2, now fully available for physics analysis. The talk will discuss the key features of PPS alignment and optics calibrations developed from scratch. The reconstructed proton distributions, performance of the PPS simulation and finally validation of the...
We discuss strategies for comparisons of nonperturbative and lattice QCD predictions for collinear PDFs at large partonic momentum fractions x with high-energy experiments. While nonperturbative approaches offer increasingly complete predictions about the nucleon and meson structure at energies below 1 GeV, experimental measurements at energies above 1 GeV rely on perturbative QCD...
We present theoretical results with soft-gluon corrections for two separate processes: (1) the production of a single top quark in association with a W boson in the Standard Model; and (2) the production of a single top quark in association with a heavy Z' boson in new physics models with or without anomalous couplings. We show that the higher-order corrections from soft-gluon emission are...
We present the forward rapidity gap spectra from proton-lead (pPb) collisions for both pomeron-Pb and pomeron-p topologies measured at CMS. The analysis is performed over 10.4 units of pseudorapidity at a center-of-mass energy of 8.16 TeV, almost 300 times higher than previous measurements of diffractive production in proton-nucleus collisions. For the pomeron-Pb topology, the cross-section...
Hard exclusive meson production is a well established tool to study the 3D nucleon structure in terms of the transverse position and the longitudinal momentum component of the partons. The QCD factorisation mechanism in the "nearly forward region" ($t/Q^{2}$ small) can be divided into a hard part, described by perturbative QCD (pQCD) and in two general structure functions, the GPDs for the...
The electro-weak interactions of the top quark are tested at the LHC by measurements of electro-weak single top quark production, of associated production processes of top quarks with gauge bosons and of top quark decay. In this contribution, the most recent ATLAS results are discussed, including measurements of the differential cross section for ttZ and ttgamma production using the full run 2...
We point out a problem in the phenomenological definition of the valence partons inside the proton. Parton degrees of freedom are definitively classified in the Euclidean path-integral formulation of the hadronic tensor in QCD. They include the valence and connected sea partons, the connected sea antipartons, and the disconnected sea partons and antiprotons. We resolve the problem by showing...
We propose the inclusive hadroproduction of a heavy-light dijet system, as a new channel for the investigation of high energy QCD. We build up an hybrid factorization that incorporates a partial next-to-leading BFKL resummation inside the standard collinear description of observables. We present a detailed analysis of different observables: cross-section summed over azimuthal angles and...
The Belle II experiment at the SuperKEKB energy-asymmetric $e^+ e^-$ collider is a substantial upgrade of the B factory facility at the Japanese KEK laboratory. The design luminosity of the machine is $8\times 10^{35}$ cm$^{-2}$s$^{-1}$ and the Belle II experiment aims to record 50 ab$^{-1}$ of data, a factor of 50 more than its predecessor. With this data set, Belle II will be able to measure...
The muon campus program at Fermilab includes the Mu2e experiment that will search for a charged-lepton flavor violating processes where a negative muon converts into an electron in the field of an aluminum nucleus, improving by four orders of magnitude the search sensitivity reached so far.
Mu2e’s Trigger and Data Acquisition System (TDAQ) uses {\it otsdaq} as its solution. Developed at...
Possibilities for inclusive diffraction in electron-proton/nucleus collider, EIC in the US are analyzed. We find that thanks to the excellent forward proton tagging, the EIC will be able to access the wider kinematical range of longitudinal momentum fraction and momentum transfer of the leading proton than at HERA. This opens up the possibilities of measurement of subleading diffractive...
We present the results of a comprehensive new Monte Carlo analysis of high-energy lepton-lepton, lepton-hadron and hadron-hadron scattering data to simultaneously determine parton distribution functions (PDFs) in the proton and parton to hadron fragmentation functions (FFs). The analysis includes all available semi-inclusive deep-inelastic scattering and single-inclusive $e^+ e^-$ annihilation...
Using a recent extraction of deeply virtual Compton scattering (DVCS) Compton form factors, done within the PARTONS framework, we derive timelike Compton scattering (TCS) amplitudes and calculate TCS observables only assuming leading-twist dominance. In the framework of collinear QCD factorization, the leading-twist scattering amplitudes for DVCS and TCS are intimately related thanks to...
Jets are collimated sprays of hadrons created by the fragmentation of high energy partons, and serve as an experimental tool for studying quantum chromodynamics. In particular, we can explore the properties of parton showers and jet evolution by measuring jet sub-structure. One of the techniques that allows experimental access to the parton shower is the jet grooming technique called SoftDrop....
We show that the cross section for the diffractive dissociation of a small onium off a large nucleus conditioned to a minimum rapidity gap can be identified to a simple classical observable on the stochastic process representing the quantum evolution of the onium in the QCD dipole model. This holds true in the parametric limit defining the geometric scaling region. Such an identification...
LHC collisions can act as a source of photons in the initial state, in addition to the more standard quark and gluon initiated processes. This mechanism often plays an important role in the production of particles with electroweak couplings, and a precise account of photon-initiated (PI) production at the LHC is a key ingredient in the LHC precision physics programme. While one approach to...
We will present results on Spin Density Matrix Elements (SDMEs) measured in hard exclusive $\rho^{0}$ meson muoproduction on the proton at COMPASS using 160 GeV/c polarised $\mu^{+}$ and $\mu^{-}$ beams scattering off a liquid hydrogen target. The measurement covers the range 5 GeV/$c^{2}$ < $W$ < 17 GeV/$c^{2}$, 1.0 (GeV/$c$)$^{2}$ < Q$^{2}$ < 10.0 (GeV/$c$)$^{2}$ and 0.01 (GeV/$c$)$^{2}$...
Building upon the most recent CT18 global fit, we present a new calculation of the photon content of proton based on an application of the LUXqed formalism. In this work, we explore two principal variations of the LUXqed ansatz. In one approach which we designate CT18lux, the photon PDF is calculated directly using the LUXqed formula for all scales, $Q$. In an alternative realization, CT18qed,...
The LHCb experiment at the Large Hadron Collider (LHC) is suited for studying how hadrons are formed from scattered quarks and gluons, collectively referred to as partons, in energetic proton-proton collisions. The hadronization process, conventionally described in terms of non-perturbative fragmentation functions in collinear factorization, can be learned in full picture at present via...
The proposed high luminosity high energy Electron Ion Collider (EIC) will explore the proton/nuclear structure, search for gluon saturation and precisely determine the nuclear parton distribution functions (nPDFs) in a wide x-$Q^{2}$ phase space. Heavy flavor and jet measurements at the future EIC will allow us to better constrain the nPDFs within the poorly constrained high Bjorken-x region,...
It is common lore that Parton Distribution Functions (PDFs) in the $\overline{\text{MS}}$ factorization scheme can become negative beyond leading order due to the collinear subtraction which is needed in order to define partonic cross sections. We show that this is in fact not the case and next-to-leading order (NLO) $\overline{\text{MS}}$ PDFs are actually positive in the perturbative regime....
In this talk we present various measurements sensitive to non-perturbative physics performed using data collected by the ATLAS experiment at the LHC. Inclusive single diffractive dissociation (pp->pX) is studied using data collected by the ATLAS experiment at the LHC. The intact proton is reconstructed and measured in the ALFA forward spectrometer, while charged particles from the dissociative...
Photoproduction of two photons is the simplest example allowing the study of QCD factorization in a family of $2\rightarrow 3$ processes. Because of the C-symmetry, the amplitude is sensitive only to valence quarks GPDs, which makes it interesting for the GPD extraction program. Leading-order calculation, presented in [1], and the subsequent work concerning electroproduction of 2 photons [2],...
Measurements of the internal properties of jets allow QCD to be studied in a new energy regime. In this talk, we discuss recent measurements of jet substructure and jet fragmentation, which were performed using data collected by the ATLAS experiment at a centre-of-mass energy of √s=13 TeV. For jet substructure, a comprehensive suite of substructure observables are measured for jets...
Generalised parton distributions are a key tool to study the three-dimensional structure of the nucleon. They shed light on its spin structure and energy-momentum tensor properties, and motivate numerous experimental programs involving hard exclusive experiments. Based on a next-to-leading order analysis, we exhibit non-trivial generalised parton distributions with arbitrarily small imprints...
We propose a new factorized approach to QED radiative corrections (RCs) in inclusive and semi-inclusive lepton-hadron deep-inelastic scattering. The method allows the systematic resummation of the logarithmically enhanced into factorized lepton distribution and fragmentation (or jet) functions that are universal for all final states. The new approach provides a uniform treatment of RCs for the...
We present results on the inclusive and identified (pion, kaon, proton and their antiparticles) charged-particle production in single diffractive dissociation process in proton-proton collisions at $\sqrt{s}= 200$ GeV with the STAR detector at RHIC. The forward-scattered proton is measured in the Roman Pot system, while the charged particle tracks are reconstructed in the STAR Time...
A reanalysis of the model of longitudinal structure function FL(x, Q^2) at low x
and low Q^2 was undertaken, in view of the advent of the EIC. The model includes the kinematic constraint FL ∼ Q^4 as Q^2 → 0. It is based on the photon-gluon fusion mechanism suitably extrapolated to the region of low Q2.
The contribution of quarks having limited transverse momentum is treated...
We discuss mechanisms of dilepton production in proton-proton collisions with rapidity gap in the main detector and one forward proton in the forward proton detectors. This is relevant for LHC measurements by ATLAS+ALFA and CMS+TOTEM. The calculations are performed including transverse momenta of the virtual photons and using relevant off-shell matrix elements. Differential distributions in...
In this talk we will outline the connections among the inclusive jet correlator, the single-hadron fragmentation correlator, and the quark propagator, which open the way to studies of fundamental mechanisms in QCD -such as the dynamical generation of mass- by looking at the fully inclusive hadronization of a quark. In particular, we will focus on observables in semi-inclusive DIS and $e^+e^-$...
In the Standard Model, the branching ratio for Higgs boson decays to invisible final states is very small, but it can be significantly enhanced in extensions of the Standard Model. In addition, the observed Higgs boson could couple to new particles decaying into Dark Matter. This talk presents searches for Higgs boson decays to invisible final states or Dark Matter in association with the...
In this contribution a measurement is presented of several observables that are sensitive to the fragmentation of b-quarks. The measurement is based on an analysis of 36 fb−1 of sqrt(s)=13 TeV LHC data. Jets containing b-hadrons are obtained from a sample of dileptonic ttbar events. The associated set of charged-particle tracks is separated into those from the primary pp interaction vertex and...
In this talk the current status and plans are presented on the LHeC,
towards the new HEP strategy update in about 5 years time, on physics,
with emphasis on the eh-hh relation, on the machine, especially the IR,
and further detector developments. The talk also covers FCC-eh and refers
to a separate presentation of the ERL facility PERLE. It is based on the
comprehensive CDR update which...
We develop a systematic treatment of heavy-flavor hadroproduction in the framework of the General-Mass Variable-Flavor-Number Scheme (GM-VFNS). By following the idea of the Simplified-ACOT-𝜒 Scheme in Deep Inelastic Scattering (DIS), we categorize the open heavy-flavor diagrams into Flavor Excitation (FE) and Flavor Creation (FC) contributions. In order to avoid double-counting, overlapping...
The presence of a non-baryonic dark matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If dark matter interacts weakly with the Standard Model (SM) it could be produced at the LHC. The ATLAS experiment has developed a broad search program for DM candidates, including resonance searches for the mediator which would couple DM to the SM. The...
The Solenoidal Tracker at the Relativistic Heavy Ion Collider (STAR) experiment probes the gluon helicity distribution $\Delta g(x, Q^2)$ using collisions of longitudinally polarized protons at $\sqrt{s} = 200$ GeV and $\sqrt{s} = 510$ GeV. $\Delta g(x, Q^2)$ can be accessed through the double spin asymmetries $A_{LL}$ in gluon-dominated hard scattering processes via inclusive jet and di-jet...
We present results on the Central Exclusive Production of charged particle pairs $h^{+}h^{-}$ ($h = \pi, K, p$) obtained in the STAR experiment at RHIC in proton-proton collisions at center-of-mass energy of $\sqrt{s} = 200$ GeV. All final-state particles of the process $pp\to p^\prime+h^{+}h^{-}+p^\prime$ were reconstructed, including forward-scattered protons detected in the Roman Pot...
The LUXE experiment (LASER Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL. LUXE is intended to study collisions between a high-intensity optical LASER and 16.5 GeV electrons from the XFEL electron beam, as well as collisions between the optical LASER and high-energy secondary photons. The physics objective of LUXE are processes...
Exclusive emissions of vector mesons in forward directions of rapidity offer us a faultless chance to probe the proton structure at small-$x$. Here, a high-energy factorization formula is established within the Balitsky-Fadin-Kuraev-Lipatov (BKFL), given as the convolution of a impact factor depicting the forward-meson emission and of an unintegrated gluon distribution (UGD) driving the gluon...
Understanding the proton spin composition from the quarks and gluons spin polarization and their motion is important to test various kinds of sum rules and nonperturbative properties of hadrons. At the Relativistic Heavy Ion Collider (RHIC), we collide longitudinally polarized proton beams and measure the double helicity asymmetry $A_{LL}$, which is an important physical quantity for...
The Compact LInear Collider (CLIC) is a proposed TeV-scale high-luminosity electron-positron collider at CERN. CLIC will allow us to study the Higgs boson properties with very high precision. These measurements can also result in direct or indirect discovery of "new physics", Beyond the Standard Model (BSM) phenomena, which could help us to understand the nature of dark matter (DM). SM-like...
Measurements of the properties of b-hadrons and quarkonia can help deepen our understanding of strong interaction. The large b- and c-hadron yields at LHCb and excellent performance of the LHCb detector make it an ideal laboratory for such studies. This talk presents the recent experimental studies on production, decay and spectroscopy of conventional b-hadrons and quarkonia at LHCb.
LHCb is a spectrometer that covers the forward region of proton-proton collisions, corresponding to the pseudo-rapidity range 2<eta<5. Thanks to its coverage, LHCb can probe the parton distribution functions (PDF) in a phase space region unexplored by other experiments, in particular in the low-x region. Moreover LHCb data could be used to test perturbative QCD predictions. In this context the...
The data on tau neutrino is very scarce, only a few experiments have detected its interactions. At FNAL beam dump experiment DONUT, tau neutrino interaction cross-section was directly measured with a large systematical (~50%) and statistical (~30%) errors. The main source of systematical error is due to a poor knowledge of the tau neutrino flux. The effective way for tau neutrino production is...
One of the primary goals of the proposed future collider experiments is to search for dark matter (DM) particles using different experimental approaches. High energy $e^+e^-$ colliders offer unique possibility for the most general search based on the mono-photon signature. As any $e^+e^-$ scattering process can be accompanied by a hard photon emission from the initial state radiation, analysis...
In this talk we discuss different mechanisms of open-heavy flavor meson and heavy quarkonia production which contribute to inclusive and single diffractive (SD) cross-sections.
For the case of inclusive production of open heavy flavor mesons, we evaluated explicitly the contributions of the two-Pomeron and the three-Pomeron fusion. We found that the latter mechanism is significant for the...
Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as nuclei. As a future high energy nuclear physics project, an Electron-ion collider in China (EicC) has been proposed. It will be constructed based on an upgraded heavy-ion accelerator, High Intensity heavy-ion Accelerator Facility (HIAF) which is currently under...
Lead ions circulating in the LHC provide copious photonuclear interactions.
These dominate the interaction rate via ultra-peripheral collisions (UPC),
when the impact parameter of the colliding lead ions is larger than the sum of their radii.
The study of \rho^0 meson photonuclear production is important,
because its cross section in UPC at the LHC is so large that it becomes a proper...
Compact Linear Collider (CLIC) was proposed as the next energy-frontier infrastructure at CERN, allowing to study $e^{+}e^{-}$ collisions at three centre-of-mass energy stages: 380 GeV, 1.5 TeV and 3 TeV. The main goal of its high-energy stages is to search for the new physics beyond the Standard Model (SM). The Inert Doublet Model (IDM) is one of the simplest SM extensions and introduces four...
We present a new global QCD analysis of spin-averaged and spin-dependent PDFs from high-$x$ DIS and $W$ production data using a Monte Carlo approach. This analysis includes the first extraction of the helicity-dependent antiquark asymmetry $\Delta \bar{u} - \Delta \bar{d}$ using $W$ production data in $\vec{p} p$ collisions at RHIC. We also focus on the high-$x$, low-$W$ region, where...
Recent results from the ATLAS experiment on the B_c production and decays will be presented. The measurement of the ratios of the B_c+ and B+ production cross sections in proton-proton collisions at 8 TeV will be discussed.
The ATLAS experiment has performed accurate measurements of mixing and CP violation in the neutral B mesons, and also of rare processes happening in electroweak...
There have been recent updates to the three global PDF fits (CT, MSHT and NNPDF), all using significant amounts of data from the LHC, in addition to the non-LHC data sets that formed the core of previous iterations. Given the impact of the LHC data on the global PDF fits, and the impact that the new PDFs will have on physics comparisons at the LHC, it is crucial to perform a benchmarking among...
Exclusive scattering processes are especially powerful probes of the proton and nuclear structure at small $x$. In particular, the possibility to measure the total momentum transfer allows for the extraction of the spatial distribution of small-$x$ partons, including their event-by-event fluctuations[1].
More detailed information about the target structure can be obtained by studying more...
The small-$x$ quark helicity evolution equations at double-logarithmic order, with the kernel $\sim \alpha_s\ln^2 (1/x)$, had been derived previously, and the equations were solved analytically at large $N_c$ and numerically at large $N_c$ and $N_f$. (Here, $N_c$ and $N_f$ are the numbers of quark colors and flavors, respectively.) In this work, we derive the single-logarithmic corrections to...
We discuss the role of the chiral “triangle” anomaly in deeply inelastic scattering (DIS) of electrons off polarized protons employing a powerful worldline formalism which allows for the efficient computation of perturbative multi-leg Feynman amplitudes. We demonstrate how the triangle anomaly appears at high energies in the DIS "box diagram" for the polarized structure function...
We explore a new energy regime, 5 TeV, for the diboson production in proton-proton collisions using 304/pb of data collected with the CMS detector. The diboson, WW, WZ, and ZZ, cross sections are measured analyzing events with two, three or four charged leptons in the final state. The cross sections are compared with NNLO predictions and across other experiments.
Measurements of deep inelastic scattering on the deuteron with detection of the spectator nucleon in the final state (spectator tagging) represent a unique method for extracting the free nucleon structure functions and studying the nuclear modifications of bound nucleons. The detection of the spectator nucleon (with typical momenta $\sim$ 100 MeV/c in the deuteron rest frame) fixes the nuclear...
I present results for soft anomalous dimensions through three loops for several processes involving the production of top quarks. I also present some numerical results for total cross sections as well as single- and double-differential distributions, and I show that soft-gluon corrections are dominant for a large range of collider energies.
Different decompositions (sum rules) for the proton mass have been proposed in the literature. All of them are related to the energy-momentum tensor in quantum chromodynamics (QCD). In this talk, we will provide an overview and a comparison of the various mass decompositions by highlighting recent developments. Special attention will be paid to the physical interpretation of the individual...
The ALICE experiment is upgraded for LHC Run 3 in order to profit from the increase in luminosity in particular for the heavy ion data taking with an expected interaction and readout rate of 50 kHz, and to improve on the tracking resolution. The upgrades comprise replacing the Inner Tracking System with a new silicon tracker using MAPS technology, including a new tracking system in the forward...
Jets provide one of the primary tools to study the partons inside
protons. The cross section of inclusive jet production is one of the
main observables to study the hard scattering. It is well described by
pQCD in the collinear factorization framework. For proton-proton
collisions at RHIC at a center-of-mass energy $\sqrt{s} =
200~\text{GeV}$, the STAR detector provides measurements at...
Measurements of multiple electroweak bosons production at the LHC constitutes a stringent test of the electroweak sector and provides a model-independent means to search for new physics at the TeV scale. In this talk, we present recent results from the ATLAS experiment for multi-boson production in proton-proton collisions at √s=13 TeV. The measurements exploit both the leptonic and hadronic...
A unique feature of generalised parton distributions (GPDs) is their relation to the QCD energy-momentum tensor. In particular, GPDs provide access to the mechanical properties of the proton i.e. the distributions of pressure and shear stress induced by the partonic structure. In principle, these distributions can be experimentally determined in a model-independent way from the subtraction...
atest results on inclusive and differential top quark pair and single top quark production cross sections are presented using proton-proton collision data collected by the CMS experiment. The differential cross sections are measured as a function of various kinematic observables of the top quarks and the jets and leptons of the event final state. The results are confronted with precise theory...
The High-Luminosity Large Hadron Collider (HL-LHC) is expected to deliver up to 3000 fb-1 of proton-proton collisions at 14 TeV center-of-mass energy. The CMS detector will undergo significant upgrades for HL-LHC operations. We will present prospects for selected Standard Model and Higgs sector measurements with the CMS detector at the HL-LHC, and discuss potential sensitivity to several...
We investigate the exclusive photoproduction of J/ψ mesons in ultraperipheral heavy-ion collisions in the color dipole approach. We use the color dipole formulation of Glauber-Gribov theory to calculate the diffractive amplitude on the nuclear target. We compare our results to recent published data on exclusive J/ψ production in ultraperipheral lead-lead collisions at √sNN=2.76 and...
We obtain the gravitational
form factors (GFFs) and investigate their applications for the description of the mechanical properties, i.e., the distributions of pressures, shear forces inside proton, and the mechanical radius, in a light-front quark-diquark model constructed by the soft-wall AdS/QCD. The GFFs, $A(Q^2)$ and $B(Q^2)$ are found to be consistent with the lattice QCD, while the...
A measurement of the W+W- boson pair production cross section in proton-proton collisions at 13 TeV is presented. The data used in this study are collected with the CMS detector at the CERN LHC and correspond to an integrated luminosity of 35.9 fb-1. The W+W- candidate events are selected by requiring two oppositely charged leptons (electrons or muons) aiming to measure the total production...
Rare two-body decays of the top quark into a neutral bottom-quark meson plus an up- or charm-quark: $t\to {\overline B}^0+ u, c$; $t\to {\overline B}^0_{s}+ c,u$; and $t \to \Upsilon(nS)+ c,u$, are studied for the first time. The corresponding partials widths are computed at leading order in the non-relativistic QCD framework. The sums of all two-body branching ratios amount to $\mathcal{B}(t...
The LHeC provides a comprehensive physics programme with strong implications on that of the HL-LHC. We will present a chapter of the 2020 LHeC Conceptual Design Report update [1], that is firstly the implications of the precise determination of proton PDFs at the LHeC on the measurement of key SM parameters at the HL-LHC: EW mixing angle, W mass and their impact on EW precision measurements....
The form factors of the energy-momentum tensor (EMT) contain a wealth of information about the nucleon. This information can be described at the density level in terms of energy, pressure, shear forces, and angular momentum distributions inside the nucleon. In this talk, we present new results on the associated 2D densities of the energy-momentum tensor in the bag model, formulated in the...
Deeply Virtual Compton Scattering (DVCS) is the golden exclusive reaction to study Generalized Parton Distributions (GPDs). Such exclusive measurements were performed at COMPASS in 2016 and 2017 at the M2 beamline of the CERN SPS using the 160 GeV muon beam scattering off a 2.5m long liquid hydrogen target surrounded by a barrel-shaped time-of-flight system to detect the recoiling target...
We investigate the momentum transfer dependence of differential cross sections $d\sigma/dt$ in diffractive electroproduction of heavy quarkonia.
The calculations have been performed within the light-front QCD dipole formalism using realistic quarkonium wave functions determined from various potential models in the $Q\bar Q$ rest frame.
Model predictions for $d\sigma/dt$ including a...
We will discuss the sensitivity to quartic anomalous couplings between photons and W/Z bosons at the LHC using intact protons in the final state. This allows obtaining a negligible background for 300 fb$^{-1}$ of data and improves the sensitivities to anomalous couplings by two or three orders of magnitude compared to standard methods. We will also discuss the sensitivity to axion-like...
The hard scattering process in which two top-quark-antiquark pairs are produced is also called four-top-quarks production and is predicted to have a small cross-section of 12 fb in the standard model. This very rare process has not been observed yet. The background is mainly given by top-quark-antiquark production in association with heavy flavor jets. In this presentation, two analyses are...
The large dataset of about 3 ab-1 that will be collected at the High Luminosity LHC (HL-LHC) will be used to measure Higgs boson processes in detail. Studies based on current analyses have been carried out to understand the expected precision and limitations of these measurements. The large dataset will also allow for better sensitivity to di-Higgs processes and the Higgs boson self coupling....
We study the exclusive production of $J^{PC}=0^{++}$ and $0^{--}$ charmonium states in proton-proton collisions at the LHC energies. The amplitudes for $gg \to \chi_{c0}$ as well as for $gg \to \eta_c$ mechanisms are derived in the $k_{T}$-factorization approach. The $p p \to p p \eta_c$ reaction is discussed for the first time. We have discussed rapidity and transverse momentum...
Naively, the amounts of $\bar{d}$ and $\bar{u}$ in the proton were expected to be the same based on the flavor-independence of the strong coupling.
However, the muon deep inelastic scattering experiment NMC at CERN found $\bar{d}>\bar{u}$ in the proton.
Drell--Yan experiments also obtained the results consistent with it.
The Drell--Yan experiment E866 at Fermilab showed that...
The scattering of electroweak bosons tests the gauge structure of the Standard Model and is sensitive to anomalous weak boson self interactions. In this talk, we present recent results on weak-boson fusion and weak-boson scattering from the ATLAS experiment using proton-proton collisions at √s=13 TeV. We present the first observation of ZZ production via weak-boson scattering as well as...
Measurements of top quark properties using data collected by the CMS experiment at 13 TeV are presented. They include direct measurements of properties or extractions using differential cross section measurements. Among them, the latest results on top mass and its running, top Yukawa coupling, the top sector of the CKM matrix, ttbar forward backward asymmetry, CP violation effects in top quark...
The electron-ion bremsstrahlung will serve for a fast and precise luminosity measurement at the EIC. This process however, due to its long-range nature, has very unique properties which need to be carefully studied [1]. In particular, at high energies it involves the so-called beam-size effect which will be significantly amplified at the EIC. In addition, large fluxes of the coherent...
We present a new study of the central exclusive diffractive production of $f_{1}(1285)$ and $f_{1}(1420)$ mesons in proton-proton collisions within the tensor-pomeron approach [1], [2]. Two ways to construct the pomeron-pomeron-$f_{1}$ coupling are presented. We adjust the parameters of our model to the WA102 experimental data [3] and compare with predictions of the Sakai-Sugimoto model, where...
The global properties of particles can be studied through the Energy-Momentum Tensor (EMT) matrix elements. The forward EMT matrix elements allow one to construct different types of mass/energy decompositions, whereas the off-forward EMT matrix elements carry information on the distribution of energy, angular momentum, pressure and shear forces in the particles.
The structure of the EMT for...
The factorization of the differential cross section Drell-Yan and DIS has recently allowed several extractions oof TMD. The extractions are based on the double-evolution of TMD and a matching on PDF. The new results show a high sensitivity to the PDF sets that I like too discuss in this talk and that can be interesting for future analyses. Several recent results obtained by our group will be shown.
We discuss the role of intrinsic charm (IC) in the nucleon for forward production of $c$-quark (or $\bar c$-antiquark) in proton-proton collisions for low and high energies. The calculations are performed in collinear-factorization approach with on-shell partons, $k_T$-factorization approach with off-shell partons as well as in a hybrid approach using collinear charm distributions and...
Since the first surprising results on the spin structure of the proton by the EMC experiment in the late 1980s, much progress has been made in understanding the origin of the proton spin. However, the sea quark contribution to the proton spin, for example, the polarized distributions of the strange quark(anti-quark), s($\bar{s}$), is still not well constrained by experimental data. Since the...
The next data-taking campaign RUN-III will double the integrated luminosity the LHC accumulated in 10 years of operation. The Run-III will be the herald of the HL-LHC era, an era when 90% of total LHC integrated luminosity (4 ab-1) will be accumulated allowing ATLAS to perform several precision measurements to constrain the Standard Model Theory (SM) in yet unexplored phase-spaces and in...
The Parton Branching (PB) approach provides a way to obtain transverse momentum dependent (TMD) parton densities. Its equations are written in terms of splitting functions and Sudakov form factors and can be solved with Monte Carlo methods. Even though the transverse momentum is known in every branching, the PB method currently uses the DGLAP splitting functions, which assume that the parton...
Vector boson scattering (VBS) represents a key test of the standard model. In order to reliably extract the electroweak contribution to this process, which probes the triple and quartic gauge couplings, a good understanding of the QCD background is necessary. We present a study of the QCD contribution to same-sign W production in association with at least two jets at the LHC within the High...
The Pierre Auger Observatory is the world largest extensive air shower
detector. Based on two detection techniques, namely fluorescence telescopes
for the observation of the longitudinal development and water Cherenkov
detectors for particles at ground, this experiment can be used not only as a
cosmic ray observatory, but also to study the basic properties of hadronic
interactions...
Experimental data from Belle Collaboration for the transverse polarization of $\Lambda$'s measured in $e^+e^-$ annihilation processes are used to extract the polarizing fragmentation function (FF) within a TMD approach.
We consider both associated and inclusive $\Lambda$ production, showing a quite consistent scenario. Good separation in flavor is obtained, with four independent FFs....
We present the first determination of transverse momentum dependent (TMD) photon densities with the Parton Branching (PB) method. The photon distribution is generated perturbatively without intrinsic photon component. The input parameters for quarks and gluons are determined from fits to precision measurements of deep inelastic scattering (DIS) cross sections at HERA. The TMD densities are...
Exclusive vector meson production is a powerful process to probe the gluonic structure of protons and nuclei at small Bjorken-$x$, and it also makes it possible to study the geometry of the nuclei in the transverse plane. An accurate description of the process requires us to go beyond the leading order and include corrections of higher orders. These include relativistic corrections to the...
Latest results from the VBS process all Run 2 will be presented.
The LHCb detector is currently being upgraded to be able to take data at higher luminosities and with greater efficiency in Run3. This involves replacement of many subdetector systems, including the vertex detector, upstream tracker, the photodetectors of the ring-imaging Cherenkov detectors, and the downstream tracker. Equally important will be a complete redesign of the data-acquisition...
The energy-energy correlator (EEC) is an event shape observable which probes the angular correlations of energy depositions in detectors at high energy collider facilities, which it has been extensively investigated in the context of precision QCD. In this work we introduce a novel definition of EEC adapted to the Breit frame in deep-inelastic scattering. In the back-to-back limit, the...
Color Glass Condensate (CGC) effective field theory (EFT) at leading order describes well the Deep Inelastic Scattering (DIS) inclusive cross section data at small-x as measured by the HERA experiments [1-3]. Recently the inclusive DIS impact factors have been calculated in Next-to-Leading Order (NLO) accuracy in CGC EFT [4-6], and the soft gluon divergence present at NLO has been factorized...
We perform a quantitative study of different methods used to solve evolution equations in QCD ($\alpha_s$, PDFs, TMDs).
We highlight differences and similarities between numerical and analytical solutions, focusing on the $q_T$ spectrum of Drell-Yan pair production analysed in the context of TMD/SCET-factorisation vs. qT-resummation formalism.
The final aim is to provide a reliable...
We derive the transverse momentum dependent factorization and resummation formula of the unpolarized transverse momentum distribution for the single hadron production with the thrust axis in an electron-positron collision. Two different kinematic regions are considered, including small transverse momentum limit and joint transverse momentum and threshold limit. Using effective theory methods,...
We will discuss the sensitivity of the $\gamma \gamma \to \tau^+ \tau^-$ process in ultraperipheral Pb+Pb collisions on the anomalous magnetic moment of $\tau$ lepton ($a_{\tau}$) at LHC energies. We derive the corresponding cross sections by folding the elementary cross section with the heavy-ion photon fluxes and considering semi-leptonic decays of both $\tau$ leptons in the fiducial volume...
The factorization of short-distance partonic cross sections from universal non-perturbatively-generated kinematic distributions is fundamental to phenomenology at hadron colliders. It has been predicted however that certain observables cannot be factorized in the usual way, even at high energies. Specifically, observables that are sensitive to momenta transverse to the direction of an...
We use Lipatov's high energy effective action to determine the next-to-leading order corrections to Higgs production in the forward region. As a new element we provide a proper definition of the desired next-to-leading order coefficient within the high energy effective action framework, extending a previously proposed prescription. We further propose a subtraction mechanism to achieve for...
Many theories beyond the Standard Model (BSM) predict the existence of new, heavy resonances that may decay in leptonic final states. This talk presents the search for physics BSM in final states with an electron or muon, and missing transverse momentum. The data was obtained with the CMS detector using full Run 2 luminosity.
In this talk I will present a study of transverse polarization of lambda-hyperons in single-inclusive leptonic annihilation (SIA). We show that when the transverse momentum of the lambda-baryon is measured with respect to the thrust axis, a transverse momentum dependent (TMD) formalism is required and the polarization is generated by the TMD polarizing fragmentation function (TMD PFF),...
We present an impact study of future EIC measurements on our knowledge of PDFs, using the JAM Monte Carlo global QCD analysis framework. We study the effect of EIC pseudo-data for polarization asymmetries on quark and gluon helicity distributions in the proton. An overview of the impact of future inclusive DIS and parity-violating DIS data on unpolarized PDFs is also shown.
We present new results on 2- and 3-loop heavy flavor corrections
to polarized and unpolarized DIS.
This includes a consistent treatment of
$\gamma_5$ which enables the extension
of massive operator matrix elements and the variable flavor
number scheme to the polarized case.
We report new measurements of the production cross sections of pairs of charged pions and kaons as a function of their fractional energies as well as azimuthal asymmetries of back-to-back pairs of charged and neutral mesons. The former measurement aims at either identifying dihadron cross sections in terms of single-hadron fragmentation functions, or providing a means to characterise the...
The Precision Proton Spectrometer (PPS) is a new subdetector of CMS introduced for the LHC Run 2, which provides a powerful tool for advancement of BSM searches.The talk will present the new results on exclusive diphoton, Z+X, and diboson production explored with with PPS, illustrating the unique sensitivity which can be achieved using proton tagging. The upcoming Run 3 will bring new...
Supersymmetry (SUSY) provides elegant solutions to several problems in the Standard Model, and searches for SUSY particles are an important component of the LHC physics program. Naturalness arguments for weak-scale supersymmetry favour supersymmetric partners of the gluons and third generation quarks with masses light enough to be produced at the LHC. Moreover, the direct production of...
The hadronization or fragmentation, where a struck quark transforms into color-neutral hadrons, is an effective tool to probe the confinement dynamics as well as the characteristic time-scales involved in the process. These time-scales elucidate our understanding of the color-neutralization and subsequent non-perturbative formation of the observed hadrons. This talk will report the first-ever...
We describe an analysis comparing the $p\bar{p}$ elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96~TeV to that in $pp$ collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections extrapolated to a center-of-mass energy of $\sqrt{s} =$ 1.96 TeV are compared with the D0...
The dynamical structure of hadronic matter is encoded in two non-perturbative, Transverse-Momentum-Dependent (TMD) partonic densities, the TMD distribution and fragmentation functions. TMD PDFs describe the way partons are arranged in nucleons, while TMD FFs are related to the mechanism of hadronization.
A successful phenomenological extraction of these functions relies on their universality...
While the unpolarized valence quark ($d$ and $u$) distributions are well determined from DIS experiments, the sea quark counterparts, $\bar{d}$ and $\bar{u}$, are much less constrained, in particular, near the valence region. Measurements of $W^+/W^-$ production ratio in $pp$ collider experiments, such as the STAR experiment at RHIC, are sensitive to the $\bar{d}/\bar{u}$ ratio at leading...
Dijet processes can be used in several ways to probe the nuclear initial state. Exclusive dijet photoproduction in ultra-peripheral heavy-ion collisions has recently been suggested as a probe of the gluon Wigner distribution. In particular, the angular correlation of exclusive dijets can assess the azimuthal anisotropy of the gluon distribution in the nuclear target. In this talk, we present...
The Higgs boson pair production via gluon fusion at high-energy hadron colliders, such as the LHC, is vital in deciphering the Higgs potential and in pinning down the electroweak symmetry breaking mechanism. In this talk, I will present the NNNLO QCD calculations in the infinite top-quark mass limit and predictions for both the inclusive and differential cross-sections. At the inclusive...
We present results of our calculations of cross sections of inclusive and diffractive dijet photoproduction in ultraperipheral collisions (UPCs) of heavy ions at the CERN Large Hadron Collider using next-to-leading order perturbative QCD. We demonstrate that our approach provides a good description of the dijet cross section measured by the ATLAS Collaboration, which exhibits 10-20% nuclear...
Recently, jet measurements in DIS events close to Born kinematics have been proposed as a new probe to study transverse-momentum-dependent (TMD) PDFs, TMD fragmentation functions, and TMD evolution. We report measurements of lepton-jet momentum imbalance and hadron-in-jet correlations in high-Q2 DIS events collected with the H1 detector at HERA. The jets are reconstructed with the kT algorithm...
The future Measurement of a Lepton-Lepton Exclusive Reaction (MOLLER) experiment will run at Jefferson Lab in Hall A. MOLLER will make an ultra-precise measurement of the weak charge of the electron, 5x more precise than E158 and with an uncertainty on the weak mixing angle that is on par with the two collider measurements at the Z-pole. The parity-violating asymmetry in the scattering of...
We present results of our studies of diffractive dijet photoproduction at the recently approved electron-ion collider (EIC) at BNL. Apart from establishing the kinematic reaches for various beam types, energies and kinematic cuts, we make precise predictions at next-to-leading order (NLO) of QCD in the most important kinematic variables. We show that the EIC will provide new and more precise...
n recent years there has been a great deal of effort to search for collectivity in small collision systems. Ultra-peripheral pPb events offer the possibility to study γ-proton collisions at a center of mass energy of several hundred GeV. Such collisions provide a new arena in which to search for collectivity. The CMS experiment has identified a large sample of γ-Pb collisions by selecting very...
Di-Higgs final states can arise through non-resonant production of two Higgs bosons and through potential heavy states decaying to two Higgs boson. This talk presents searches in several Higgs boson decay channels using Run2 Data at 13 TeV and prospects at HL-LHC.
In the context of the Transverse-Momentum-Dependent (TMD) description of the nucleon structure, it is important to study the distributions of the transverse-momentum squared $P_T^2$ and the amplitudes of the azimuthal modulations (azimuthal asymmetries) of charged hadrons produced in Semi-Inclusive DIS. The $P_T^2$ - distributions and the azimuthal asymmetries can be related to the intrinsic...
We report a study of two-particle angular correlations in
deep-inelastic scattering off a proton target measured with
the CLAS12 detector at Jefferson Lab. We discuss both
pion-pion and pion-proton correlation functions. Such measurements
complement ongoing studies at collider experiments and addresses open
questions regarding hypothetical collective behaviour in "small systems". ...
In the Ingelman-Schlein approach for hard diffraction the cross sections can be factorized into diffractive PDFs and perturbatively calculable partonic coefficient functions. The diffractive PDFs can be determined in a global QCD analysis using data for diffractive processes in DIS in a similar manner as for inclusive PDFs. However, it has been observed that this factorization breaks down in...
The LHeC and the FCC-eh offer unique prospects for the measurement of top properties in energy frontier, luminous ep scattering. An update of the 2012 Conceptual Design Report was produced last year [1]. In this talk we will revisit the determination of the top mass through inclusive measurements. In addition, we will address the possibilities for precise measurements of $Wtq$ and $\gamma tq$...
Studying the partonic and spin structure of the nucleon via Semi-Inclusive measurements of DIS (SIDIS) is one of the most important objectives of the COMPASS experiment (CERN, SPS). Nucleon spin (in)dependent azimuthal asymmetries accessible in single-hadron and hadron-pair production in SIDIS encode information on both the partonic structure of the nucleon and the fragmentation process....
The differential cross section measurements of the production of a pair of opposite-charged leptons as a function of pt and phi* in various bins of its invariant mass M are presented. The results are obtained using proton-proton collision data recorded with the CMS detector at the LHC. Measurements are also compared to state-of-the-art generators as well as TMD based predictions.
Charged particle multiplicity spectra and hadron entropies are measured using the H1 detector at HERA, where positrons of energy 27.6 GeV collided with protons of energy 920 GeV. For the analysis, data on deep-inelastic scattering in the momentum transfer range 5<𝑄2<100 GeV2 and inelasticity range 0.0375<𝑦<0.6 are used. The observed multiplicity spectra of charged hadrons are compared to Monte...
Higgs production cross sections at LHeC (FCC-eh) energies are as large (larger than) those at future Z-H $e^+e^-$ colliders. This provides alternative and complementary ways to obtain very precise measurements of the Higgs couplings, primarily from luminous, charged current DIS. Recent results for LHeC and FCC-eh [1] are shown and their combination is presented with pp (HL-LHC) cross sections...
Many decades of experiments in deep inelastic scattering (DIS) of lepton beams off nucleons have mapped out the momentum distributions in the nucleon in terms of one-dimensional (1-D) parton distribution functions (PDFs). While these measurements provided significant insight into the structure of the nucleon, many important and interesting aspects of the nucleon structure cannot be revealed in...
Following our recent Monte Carlo determination of the pion’s PDFs from Drell-Yan (DY) and leading neutron electroproduction data from the Jefferson Lab Angular Momentum (JAM) collaboration, we extend the analysis by including effects from threshold resummation. At higher orders in the strong coupling, $\alpha_S$, soft gluon emissions cause large logarithmic corrections, which become important...
Charged current events in an exclusive electroproduction process have not been much discussed up to now. The reason is simple as the smallness of the weak coupling prevents exclusive cross-sections from being large enough to allow sufficient counting rates at existing electron-nucleon facilities.The very high luminosity anticipated at planned high energy electron ion colliders should open...
A parton branching (PB) formulation for the QCD evolution of transverse momentum dependent (TMD) parton distribution functions has been recently developed. With the implementation of this in the evolution program updfevolv and the parton shower Monte Carlo event generator Cascade3, PB TMD predictions for observables in broad kinematic regimes can be made. In this talk I focus on recent PB TMD...
Dihadron beam spin asymmetries provide a wide range of insights into nucleon structure and hadronization. Recent measurements at CLAS12 provide the first empirical evidence of a nonzero $G_1^\perp$, the parton helicity-dependent dihadron fragmentation function (DiFF) encoding spin-momentum correlations in hadronization. These measurements also allow for a point-by-point extraction of the...
The measurements of inclusive deep-inelastic electron-proton scattering (DIS) cross sections at high center-or-mass energies offer a unique opportunity for precision tests of electroweak interactions. In this talk we revisit electroweak effects in DIS and discuss the combined determination of parameters of electroweak theory together with parton distribution functions of the proton. Using...
The LHeC and the FCC-eh will extend the kinematic region presently available in DIS to very small values of $x$ in the perturbative $Q^2$ region. Therefore, they will be able to establish the dynamics of the strong interaction at small $x$ or high energies, and unravel the existence of a new non-linear regime of QCD where parton densities are expected to saturate. In this talk we will review...
We describe the status of the ATLAS Forward Proton Detectors (AFP and ALFA) for LHC Run 3. The expected performance of the Tracking and Time-of-Flight Detectors, the electronics, the trigger, and the readout and detector control and data quality monitoring are described in some detail. Finally, the physics interest and the beam optics and detector options for participation at the HL-LHC are discussed.
I will report on an ongoing effort towards calculating the N4LO perturbative QCD corrections to the DIS total inclusive cross-section. We are developing a method based on differential equations and series expansion in the inverse Bjorken parameter. As a byproduct our calculation should also deliver analytic or at least precise numerical approximations for the four-loop splitting functions.
We study the nuclear modification for the large Bjorken-$x$ dijet cross-section in eA deeply in-elastic scattering (DIS) process for electron-ion collider (EIC) kinematics. We use the generalized High-Twist approach in our calculation, which do not perform twist expansion. Under small longitudinal momentum transfer approximation, the nuclear modified cross section can be approximately...
A modern renaissance in how to understand and use quantum mechanics has arrived in nuclear and particle physics. Quantum tomography bypasses model-dependent assumptions and unnecessary theoretical superstructure that characterized the old use of quantum mechanics, which as designed for exclusive processes. A modern description of inclusive reactions is closely tied to the correlations of what...
Semi-Inclusive Deep-Inelastic Scattering (SIDIS) is one of the processes that allow us to extract information about Transverse Momentum Distributions (TMDs) and will be the main access to TMDs at the EIC.
Using sensitivity coefficients and reweighing techniques, we provide an estimate of the impact that EIC data will have on unpolarized Transverse-Momentum Dependent (TMD) Parton Distribution...
We present the first Monte Carlo based global QCD analysis of spin-averaged and spin-dependent parton distribution functions (PDFs) that includes nucleon isovector matrix elements in coordinate space from lattice QCD. We investigate the degree of universality of the extracted PDFs when the lattice and experimental data are treated under the same conditions within the Bayesian likelihood...
To meet new TDAQ buffering requirements and withstand the high expected radiation doses at the high-luminosity LHC, the ATLAS Liquid Argon Calorimeter readout electronics will be upgraded. The triangular calorimeter signals are amplified and shaped by analogue electronics over a dynamic range of 16 bits, with low noise and excellent linearity. Developments of low-power preamplifiers and...
The cross section of hadronically decaying W/Z bosons at the high transverse momentum in proton proton collisions at 13 TeV measured by CMS will be presented. The W/Z bosons are identified using jets with the characteristic jet substructure. The measured results are compared with various MC predictions.
The Electron-Ion Collider will be the first collider to use both polarized electron beams and polarized proton and light ion beams. This will offer unique opportunities to study the structure of protons and nuclei and to answer fundamental questions in QCD.
The uncertainties on the polarization measurement translate directly into the uncertainties of final physics observables. Hence, a...
Using the standard BFKL approach, with partial inclusion of next-to-leading order effects, we proposed the inclusive hadroproduction of a Higgs boson and of a jet, featuring large transverse momenta and well separated in rapidity, as a new channel to probe the Balitsky-Fadin-Kuraev-Lipatov (BFKL) dynamics. predictions are presented for cross-sections and azimuthal angle correlations in...
We present the status for the measurement of cross sections of weak boson production as a function of the boson's kinematics, by the STAR experiment at RHIC. Results combine data from unpolarized p+p collisions at $\sqrt{s}$ = 500 and 510 GeV collected during the 2011, 2012, 2013, and 2017 runs, corresponding to an integrated luminosity of 700 pb$^{-1}$. The differential $Z^{0}$ cross section,...
Measurements of W/Z-boson production in association with jets are an important test of perturbative QCD prediction and also yield information about the parton distribution functions of the proton. First, differential cross-sections for Z-boson production in association with jets using proton-proton collisions collected by the ATLAS experiment are presented. The data are compared to...
The predicted high sensitivity of the nuclear modification factor for $K^{-}$ in
SIDIS due to the QCD based effect of medium-induced flavour conversion in the fragmentation function is studied at the HERMES experiment. Unlike $\pi^{+}$, $\pi^{-}$ and $K^{+}$, nuclear modification factor for $K^{-}$ is expected to increase at high values of the Bjorken variable $x_B$ and hadron fractional...
We develop a non-perturbative model for valence PDFs based on the quark interactions in the mean field of the nucleonic interior. The model is based on the separation of three valence quarks from the residual nucleon system which is the source of the mean field. The PDFs are calculated within effective light-front diagrammatic approach which allows to introduce light-front valence quark and...
Di-hadron angular correlations are a sensitive probe of the Color Glass Condensate (CGC) at the Electron Ion Collider, and higher order corrections are needed for a quantitative analysis. Here we present our preliminary results for the calculation of next to leading order corrections to di-hadron production in Deep Inelastic Scattering (DIS) at small Bjorken x. We model the target nucleus as a...
We present the in-medium modification of pentaquark , $\Theta^+$, using chiral SU(3) hadronic mean field model in hot and dense asymmetric nuclear matter. The in-medium properties of hadrons within the chiral model are investigated through the modification of scalar fields $\sigma$, $\zeta$ and $\delta$ and the vector fields $\omega$ and $\rho$. The effects of finite temperature and density...
Describing hadronic structure in terms of its constituent partonic degrees of
freedom remains an open subject. On the theoretical side, GPDs and TMDs are
expected to play a central role drawing three-dimensional images of hadrons.
Thus high priority is being given to experiments that can yield data which may
be interpretable in terms of these quantities. Among all possibilities, that...
In this talk, we present a model-independent calculation of the $x$-dependence of pion valence PDF with the large-momentum effective theory approach. In this calculation we adopt the most up-to-date theoretical developments on the systematic corrections, which include the hybrid renormalization scheme that rigorously renormalizes the lattice matrix elements at both short and long distances, as...
We study production of three isolated photons at the energy of Large Hadron Collider [1] in the Parton Reggeization Approach [2,3], which is based on high-energy factorization, Lipatov effective theory [4] and new unintegrated PDFs, obtained in modified multi-Regge kinematics approximation for QCD scattering amplitudes [5]. It is shown that data from ATLAS Collaboration can be described after...
In the present work, we investigate the transverse momentum dependent quark-gluon–quark correlation function by using the light-front quark-diquark model. We calculate the time-reversal-odd interaction-dependent twist-3 parton distributions.
We describe the performance of the ATLAS Forward Proton Time-of-Flight detector (ToF) in Run 2 and the upgrades made to the ToF for operation in Run 3. We describe test beam results and picosecond laser test results and the expected operational parameters and performance of the new ToF in Run 3.
ATLAS is preparing for the HL-LHC upgrade, where integrated and instantaneous luminosity will reach unprecedented values. For this, an all-silicon Inner Tracker (ITk) is under development with a pixel detector surrounded by a strip detector. The strip system consists of 4 barrel layers and 6 endcap disks. After completion of FDRs in key areas, such as Sensors, Modules, Front-End electronics...
The Tile Calorimeter (TileCal) is a sampling hadronic calorimeter covering the central region of the ATLAS experiment. TileCal uses steel as absorber and plastic scintillators as active medium. The scintillators are read-out by the wavelength shifting fibres coupled to the photomultiplier tubes (PMTs). The analogue signals from the PMTs are amplified, shaped, digitized by sampling the signal...
We investigate the tomographical structure of pion and kaon in light cone quark model (LCQM). In particular, we study the parton distribution amplitude (PDA) of pion and kaon. We obtain the parton distribution function (PDF) and the generalized parton distributions (GPDs) of the pion and kaon. The valence quark PDA and PDF of pion, after QCD evolution, are found to be consistent with the data...
One of the important goals at the future $e^+e^-$ colliders is to measure the top-quark mass and width in a scan of the pair production threshold. However, the shape of the pair-production cross section at the threshold depends also on other model parameters, as the top Yukawa coupling, and the measurement is a subject to many systematic uncertainties. Presented in this work is the most...
