Dr
Michael Strickland
(Kent State University)
07/03/2014, 14:00
Mr
Scott Pratt
(MSU)
07/03/2014, 14:05
Charge correlations provide the means to infer the quark chemistry of the super-hadronic matter created in a heavy-ion collisions. I will show how results from STAR appear confirm the creation of a chemically equilibrated QGP.
Mr
Jesse Buxton
(The Ohio State University Department of Physics)
07/03/2014, 14:30
We employ a simple kinematic model based on the superposition of p+p collisions, relativistic geometry, and final-state hadronic rescattering to predict a number of hadronic observables in √sNN = 2.76 TeV Pb+Pb collisions. The current study uses a model similar to [Humanic10], but includes an additional procedure (“squeeze procedure”) to better fit the predicted pseudorapidity distribution to...
Andrew Kubera
(The Ohio State University)
07/03/2014, 14:55
A comparison of azimuthal di-hadron correlation yield ratios is made between a simple rescattering model and experimental p+p and Pb+Pb data taken with the ALICE detector at $\sqrt{s_{NN}}$ = 2.76TeV. Event by event azimuthal correlations are created from hadrons associated with high-$p_T$ trigger particles, producing peaks in the per-trigger associated multiplicity distribution at...
Isaac Upsal
(Ohio State University)
07/03/2014, 15:20
Non-central heavy ion collisions provide a system with non-zero net angular momentum. If the spin degrees of freedom equilibrate in the fireball, then emitted particles are expected to exhibit a net spin. Lambda baryons are self analyzing, meaning proton daughters are emitted preferentially in the direction of the spin, making the $\Lambda$ an ideal candidate for the determination of the net...
Mr
Chun Shen
(The Ohio State University)
07/03/2014, 16:20
Photons are a penetrating probe of the hot medium formed in heavy-ion collisions, but they are emitted from all collision stages. At photon energies below 2-3 GeV, the measured photon spectra are approximately exponential and can be characterized by their inverse logarithmic slope, often called “effective temperature” T_eff. Modeling the evolution of the radiating medium hydrodynamically, we...
Prof.
Ulrich Heinz
(The Ohio State University)
07/03/2014, 16:45
I will report on the discussions at the EMMI Rapid Reaction Task Force meeting on the ``Photon flow puzzle" that happens at GSI the week before this meeting. The state of the art in numerical simulations and experimental data will be discussed, as well as some possibly interesting future measurements.
Dr
Rosi Reed
(Wayne State University)
07/03/2014, 17:10
In relativistic heavy-ion collisions a hot, dense medium of strongly interacting quarks and gluons, called the Quark Gluon Plasma (QGP), is formed. Partons that undergo a hard scatter fragment into collimated streams of particles, called jets, are a good probe because they are produced prior to QGP formation and well understood in pp collisions. In a colored medium, the fragmentation of...
Mr
Chris Yaldo
(Wayne State University)
07/03/2014, 17:35
Experiment
Talk
Proton-nucleus collisions are utilized to distinguish between initial and final state effects, which is vital for establishing a baseline for heavy-ion collisions. One of the crucial reference measurements is the jet nuclear modification factor (R_pPb) in p-Pb collisions at s_NN = 5.02 TeV at the LHC. Jets in ALICE are reconstructed using the anti-k_T jet finding algorithm combining...
Mr
Baoyi Chen
(Tsinghua University)
07/03/2014, 18:00
In comparison with J/\psi, the excited charmonium 2S-state ψ' is loosely bounded and its yield is dominantly from the B-hadron decay. Based on the transport approach, we study the double ratio of N(ψ')/N(J/ψ) from A+A collisions to that from p+p collisions at LHC energy, where N means the yield.
We found that different from bound charmonium state J/ψ whose inclusive yield and averaged...
Justin Frantz
(Ohio University)
08/03/2014, 08:15
I will present a short update on my group's work in two-particle correlations work, as well as work related to the sPHENIX upgrade.
Mr
Christopher Plumberg
(The Ohio State University)
08/03/2014, 08:30
HBT (Hanbury-Brown—Twiss) interferometry is an observational technique which plays an essential role in the extraction of the geometric and flow properties of heavy-ion collisions. In particular, azimuthally-sensitive HBT studies convey information about deformations and anisotropies in the structure of the freeze-out surface. One aspect of these studies, which is not at present well...
Mr
John Campbell
(The Ohio State University)
08/03/2014, 08:55
Collisions between uranium nuclei have been produced in the Relativistic Heavy Ion Collider and measured in the STAR detector. Due to the prolate deformation of the nuclei, fully overlapping U+U collisions offer the opportunity to produce highly anisotropic participant zones, similar in shape to mid-central Au+Au collisions, but with twice the size. The larger fireball should be characterized...
Mr
Radoslaw Ryblewski
(Kent State University)
08/03/2014, 10:40
Experimental and theoretical studies of relativistic heavy-ion collisions showed that the behavior of matter produced in such collisions is very well described within hydrodynamic models.
These results brought a lot of attention to the studies of kinetic coefficients whose values determine the magnitude of important observables such as the elliptic flow. Interestingly, different theoretical...
Mr
Dennis Bazow
(The Ohio State University)
08/03/2014, 11:05
The collective expansion in relativistic heavy-ion collisions is initially highly anisotropic. Due to viscosity, this leads to strongly deformed local momentum distributions which invalidates the standard viscous hydrodynamic expansion around a local equilibrium distribution, causing a breakdown of viscous fluid dynamics à la Israel and Stewart at early times. We have developed an improved...
Mr
Jia Liu
(The Ohio State University)
08/03/2014, 11:30
Pre-equilibrium evolution of heavy-ion collision is an open problem. Now most hydrodynamic simulations for heavy-ion assume the system thermalizes immediately after the collision. In our study, we explore the free-streaming limit and assume the system thermalizes at the end of free-streaming. At the end of free-streaming, by solving collisionless Boltzmann equation, we find the gluon...
Dr
Anton Wiranata
(Central China Normal University/LBL)
08/03/2014, 11:55
The shear viscosity η and entropy density s of a hadron gas with zero baryon
number density are calculated using the Chapman-Enskog and virial expansion approaches,
respectively. Interactions are included via the K-matrix parametrization of cross sections
preserving the unitarity of the S-matrix. In the four component mixture (π − K − N − η),
a total of 57 resonances up to 2 GeV mass are...
Giovanni Antonio Chirilli
(Ohio State University)
08/03/2014, 14:35
Scattering amplitudes of proton-Nucleus or Nucleus-Nucleus collisions at high-energy are described by matrix elements of Wilson line operators - infinite gauge factors ordered along the straight lines of the fast moving particles. The energy dependence of such amplitudes is described by the evolution equation of Wilson lines with respect to the rapidity parameter - the Balitsky-JIMWLK...
Douglas Wertepny
(The Ohio State University)
08/03/2014, 15:00
We derive the cross-section for two-gluon production in heavy-light ion collisions in the saturation/Color Glass Condensate framework. This is the first-ever two-gluon production calculation including saturation effects to all orders in one of the nuclei (heavy ion) along with a single saturation correction in the projectile (light ion). The calculation of the correlation function predicted...
Dr
Mauricio Martinez Guerrero
(Ohio State University)
08/03/2014, 15:25
In the high energy limit, scattering processes can be described within the eikonal approximation, neglecting contributions which are power-suppressed at high energy. In the case of processes involving a large nuclear target, like pA or AA collisions, the Color Glass Condensate effective theory (CGC) is one of the most convenient formalisms based on the eikonal approximation. So far, the...
Dr
JONATHAN BOUCHET
(KENT STATE UNIVERSITY)
08/03/2014, 16:20
We will briefly discuss the commissioning and heavy flavor physics program of the new pixel tracker of STAR experiment at RHIC.
Mr
Michael Lomnitz
(Kent State University)
08/03/2014, 16:45
Last year, the STAR experiment at RHIC has installed a prototype of the Heavy Flavor Tracker (HFT). The motivation of the HFT detector is to enhance STAR physics capability in measuring heavy quark production with the use of direct topological reconstruction of charmed hadrons.
In this talk we will discuss aspects of the commissioning of the HFT detector in its first data taking deployment.
Prashanth Shanmuganathan
(Kent State University)
08/03/2014, 17:10
The Beam Energy Scan (BES) program at the Relativistic Heavy-Ion Collider has several physics goals, all related to understanding the phase diagram for QCD matter. One of these goals is to search for signatures of a first-order phase transition from a hadron gas to quark gluon plasma. It is generally accepted that QGP is produced at the top RHIC energies (and at the LHC), and there is much...
Dr
prabhat pujahari
(Wayne State University)
08/03/2014, 17:35
Experiment
Talk
Two-particle correlations provide information about particle production mechanisms in heavy-ion collisions.
We report on results of transverse momentum dierential two particle correlations in Pb-Pb collisions at
p
sNN = 2.76 TeV measured with the ALICE detector at the LHC. Correlation functions for unidentied
++, + and charged particle pairs as a function of pair azimuthal and...
