Mon·Nov 7, 2022Monday·November 7, 2022

1. 01*

   Unpolarized Transverse-Momentum-Dependent Parton Distributions of the Nucleon from Lattice QCD

   Lattice Parton Collaboration: Jin-Chen He🇨🇳 · Min-Huan Chu🇨🇳 · Jun Hua🇨🇳 · Xiangdong Ji🇺🇸 · Andreas Schäfer🇩🇪 · Yushan Su🇺🇸 · Wei Wang🇨🇳 · Yibo Yang🇨🇳 · Jian-Hui Zhang🇨🇳 · Qi-An Zhang

   We present a first lattice QCD calculation of the unpolarized nucleon's isovector transverse-momentum-dependent parton distribution functions (TMDPDFs), which are essential to predict observables of multi-scale, semi-inclusive processes in the standard model. We use a $N_f=2+1+1$ MILC ensemble with valence clover fermions on a highly improved staggered quark (HISQ) sea to compute the quark momentum distributions in a large-momentum nucleon on the lattice. The state-of-the-art techniques in renormalization and extrapolation in the correlation distance on the lattice are adopted. {The perturbative kernel up to next-to-next-to-leading order is taken into account}, and the dependence on the pion mass and the hadron momentum is explored. Our results are qualitatively comparable with phenomenological TMDPDFs, which provide an opportunity to predict high energy scatterings from first principles.

   hep-lathep-phPRD(2024)·60 citations
2. 02*

   Topological susceptibility, scale setting and universality from $Sp(N_c)$ gauge theories

   Davide Vadacchino🇬🇧 · Ed Bennett🇬🇧 · C.-J. David Lin🇹🇼 · Deog Ki Hong🇰🇷 · Jong-Wan Lee🇰🇷 · Biagio Lucini🇬🇧 · Maurizio Piai🇬🇧

   In this contribution, we report on our study of the properties of the Wilson flow and on the calculation of the topological susceptibility of $Sp(N_c)$ gauge theories for $N_c=2,4,6,8$. The Wilson flow is shown to scale according to the quadratic Casimir operator of the gauge group, as was already observed for $SU(N_c)$, and the commonly used scales $t_0$ and $w_0$ are obtained for a large interval of the inverse coupling for each probed value of $N_c$. The continuum limit of the topological susceptibility is computed and we conjecture that it scales with the dimension of the group. The lattice measurements performed in the $SU(N_c)$ Yang-Mills theories by several independent collaborations allow us to test this conjecture and to obtain a universal large-$N_c$ limit of the rescaled topological susceptibility.

   hep-lathep-thPoS(2023)·1 citation

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.