Speaker
Description
We present a lattice QCD analysis of unpolarised generalised parton distri-
butions (GPDs) of the proton. Our calculations are done on an ensamble with
Nf = 2 + 1 + 1 (degenerate light quarks, strange and charm quarks) twisted
mass fermions at physical mass with a clover improvement and lattice spacing
a = 0.08 fm. We use Large Momentum Effective Theory (LaMET) to anlayse
and match the quasi-GPDs to their light-cone distributions in the asymmetric
kinematic frame. Our analysis has been performed with several values of the
momentum transfer −t, from 0 to 1.2 $GeV^2$ at zero-skewness and boost up un-
til 1.7 GeV. We check the convergence in our matched light-cone distributions
for large boosts, both in the standard definition and in the Lorentz-Invariant
one. We use the quasi-GPDs to define the pseudo-GPDs in order to extract the
Mellin moments. We compute and compare them to direct calculations of the
moments from lattice QCD as well as to the phenomenology.
