Li Yuan, Xia Shi-Cheng, Alexandrou Constantia, Cichy Krzysztof, Constantinou Martha, Feng Xu, Hadjiyiannakou Kyriakos, Jansen Karl, Liu Chuan, Scapellato Aurora, Steffens Fernanda, Tarello Jacopo
School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China.
Department of Physics, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus.
Phys Rev Lett. 2022 Feb 11;128(6):062002. doi: 10.1103/PhysRevLett.128.062002.
In this work, we perform a lattice QCD study of the intrinsic, rapidity-independent soft function within the framework of large momentum effective theory. The computation is carried out using a gauge ensemble of N_{f}=2+1+1 clover-improved twisted mass fermion. After applying an appropriate renormalization procedure and the removal of significant higher-twist contamination, we obtain the intrinsic soft function that is comparable to the one-loop perturbative result at large external momentum. The determination of the nonperturbative soft function from first principles is crucial to sharpen our understanding of the processes with small transverse momentum such as the Drell-Yan production and the semi-inclusive deep inelastic scattering. Additionally, we calculate the Collins-Soper evolution kernel using the quasi-transverse-momentum-dependent wave function as input.
在这项工作中，我们在大动量有效理论框架内对本征的、与快度无关的软函数进行格点量子色动力学研究。计算是使用具有N_f = 2 + 1 + 1个三叶草改进型扭质量费米子的规范系综进行的。在应用适当的重整化程序并去除显著的高扭度污染后，我们得到了在大外部动量下与单圈微扰结果相当的本征软函数。从第一性原理确定非微扰软函数对于加深我们对具有小横向动量的过程（如Drell-Yan产生和半单举深度非弹性散射）的理解至关重要。此外，我们使用准横向动量依赖波函数作为输入来计算柯林斯-索珀演化核。
