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This content will become publicly available on November 8, 2018

Title: Lattice QCD exploration of parton pseudo-distribution functions

Here, we demonstrate a new method of extracting parton distributions from lattice calculations. The starting idea is to treat the generic equal-time matrix element $${\cal M} (Pz_3, z_3^2)$$ as a function of the Ioffe time $$\nu = Pz_3$$ and the distance $$z_3$$. The next step is to divide $${\cal M} (Pz_3, z_3^2)$$ by the rest-frame density $${\cal M} (0, z_3^2)$$. Our lattice calculation shows a linear exponential $$z_3$$-dependence in the rest-frame function, expected from the $$Z(z_3^2)$$ factor generated by the gauge link. Still, we observe that the ratio $${\cal M} (Pz_3 , z_3^2)/{\cal M} (0, z_3^2)$$ has a Gaussian-type behavior with respect to $$z_3$$ for 6 values of $P$ used in the calculation. This means that $$Z(z_3^2)$$ factor was canceled in the ratio. When plotted as a function of $$\nu$$ and $$z_3$$, the data are very close to $$z_3$$-independent functions. This phenomenon corresponds to factorization of the $x$- and $$k_\perp$$-dependence for the TMD $${\cal F} (x, k_\perp^2)$$. For small $$z_3 \leq 4a$$, the residual $$z_3$$-dependence is explained by perturbative evolution, with $$\alpha_s/\pi =0.1$$.
Authors:
 [1] ;  [2] ;  [1] ;  [1]
  1. The College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
  2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Old Dominion Univ., Norfolk, VA (United States)
Publication Date:
Report Number(s):
JLAB-THY-17-2494; DOE/OR/23177-4189; arXiv:1706.05373
Journal ID: ISSN 2470-0010; PRVDAQ; TRN: US1703290
Grant/Contract Number:
AC05-06OR23177; AC02-05CH11231; FG02-04ER41302; FG02-97ER41028; PHY-1516509; PHY-1626177
Type:
Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 96; Journal Issue: 9; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society (APS)
Research Org:
Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
OSTI Identifier:
1408203
Alternate Identifier(s):
OSTI ID: 1408063