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Title: Excited state analysis in the quasi-PDF matrix elements
We study and demonstrate the ground-state extrapolation of the unpolarized and polarized nucleon quark quasi-PDF matrix elements in a highly boosted hadron frame on the lattice. The calculation is done using the Wilson clover quark on a MILC’s dynamical Nf = 2+1+1 highly improved staggered quarks (HISQ) ensemble with one step hypercubic smearing, and with the lattice spacing a∼0.09 fm and pion mass 310 MeV. Applying the Gaussian momentum-smeared quark sources and comparing various fits in 1-, 2-, and 3-state fitting models, we show that excited state contributions can be under control in the lattice calculation of the nucleon quark quasi-PDF matrix elements.  more » « less
Award ID(s):
1653405
PAR ID:
10097128
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
The 36th Annual International Symposium on Lattice Field Theory (LATTICE2018)
Volume:
334
Page Range / eLocation ID:
097
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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