[NT/RBRC hybrid seminar] Perturbative Calculations of Gravitational Form Factors at Large Momentum Transfer

by Dr Xuanbo Tong (Chinese University of Hong Kong)

Friday 13 May 2022, 11:00 → 12:00 US/Eastern

Large Seminar Room (https://bnl.zoomgov.com/j/1617203107?pwd=MUpFWHdtT2hYUjk1RTVPN3U1bnBHUT09)

Gravitational form factors (GFFs), as the matrix elements of the energy-momentum tensor, are the fundamental ingredients to probe the internal structure of hadrons. In this talk, we will present a perturbative QCD analysis of the gravitational form factors of nucleon at large momentum transfer. We will derive the explicit factorization formula of the GFFs in terms of twist-3 and twist-4 light-cone distribution amplitudes of nucleon at the leading order. Power behaviors for these GFFs are obtained from the computations. Numeric results of the quark and gluon contributions to various GFFs are presented with model assumptions for the distribution amplitudes in the literature. We will  also present the perturbative calculations of the scalar form factor $\langle P'|F^2| P\rangle$ for pion and proton at large momentum transfer.