Nonperturbative determination of the Collins-Soper kernel from quasitransverse-momentum-dependent wave functions
/ Authors
Mingming Chu, Zhigang Deng, Jun Hua, X. Ji, A. Schafer, Yushan Su, Peng Sun, Wei Wang, Yi-Bo Yang, Jun-jie Zeng
and 3 more authors
/ Abstract
In the framework of large-momentum effective theory at one-loop matching accuracy, we perform a lattice calculation of the Collins-Soper kernel which governs the rapidity evolution of transverse-momentum-dependent (TMD) distributions. We first obtain the quasi TMD wave functions at three different meson momenta on a lattice with valence clover quarks on a dynamical HISQ sea and lattice spacing $a=0.12$~fm from MILC, and renormalize the pertinent linear divergences using Wilson loops. Through one-loop matching to the light-cone wave functions, we determine the Collins-Soper kernel with transverse separation up to 0.6~fm. We study the systematic uncertainties from operator mixing and scale dependence, as well as the impact from higher power corrections. Our results potentially allow for a determination of the soft function and other transverse-momentum dependent quantities at one-loop accuracy.
Journal: Physical Review D