Abstract
In this study, we present a determination of the unpolarized gluon Ioffe-time distribution in the nucleon from a first principles lattice quantum chromodynamics calculation. We carry out the lattice calculation on a 323×64 ensemble with a pion mass of 358 MeV and lattice spacing of 0.094 fm. We construct the nucleon interpolating fields using the distillation technique, flow the gauge fields using the gradient flow, and solve the summed generalized eigenvalue problem to determine the gluonic matrix elements. Combining these techniques allows us to provide a statistically well-controlled Ioffe-time distribution and unpolarized gluon parton distribution function. We obtain the flow time independent reduced Ioffe-time pseudodistribution and calculate the light-cone Ioffe-time distribution and unpolarized gluon distribution function in the MS¯ scheme at μ=2 GeV, neglecting the mixing of the gluon operator with the quark singlet sector. Finally, we compare our results to phenomenological determinations.
| Original language | English |
|---|---|
| Article number | 094516 |
| Journal | Physical Review D |
| Volume | 104 |
| Issue number | 9 |
| DOIs | |
| State | Published - Nov 1 2021 |
Funding
We would like to thank all the members of the HadStruc collaboration for fruitful and stimulating exchanges. T. K. and R. S. S. acknowledge Luka Leskovec and Archana Radhakrishnan for offering their generous help, which greatly assisted this research. T. K. is support in part by the Center for Nuclear Femtography Grants No. C2-2020-FEMT-006, C2019-FEMT-002-05. T. K., R. S. S., and K. O. are supported by U.S. DOE Grant No. DE-FG02-04ER41302. A. R. and W. M. are also supported by U.S. DOE Grant No. DE-FG02-97ER41028. J. K. is supported by U.S. DOE Grant No. DE-SC0011941. This work is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Contract No. DE-AC05-06OR23177. Computations for this work were carried out in part on facilities of the USQCD Collaboration, which are funded by the Office of Science of the U.S. Department of Energy. This work was performed in part using computing facilities at The College of William and Mary, which were provided by contributions from the National Science Foundation (MRI grant PHY-1626177), and the Commonwealth of Virginia Equipment Trust Fund. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant No. ACI-1548562. Specifically, it used the Bridges system, which is supported by NSF Grant No. ACI-1445606, at the Pittsburgh Supercomputing Center (PSC) . In addition, this work used resources at NERSC, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, as well as resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. The software codes c hroma , quda , and qp hi x were used in our work. The authors acknowledge support from the U.S. Department of Energy, Office of Science, Office of Advanced Scientific Computing Research and Office of Nuclear Physics, Scientific Discovery through Advanced Computing (SciDAC) program, and of the U.S. Department of Energy Exascale Computing Project. The authors also acknowledge the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing HPC resources, like Frontera computing system that has contributed to the research results reported within this paper. We acknowledge PRACE (Partnership for Advanced Computing in Europe) for awarding us access to the high performance computing system Marconi100 at CINECA (Consorzio Interuniversitario per il Calcolo Automatico dellItalia Nord-orientale) under the Grant No. Pra21-5389. JLAB-THY-21-3469.
| Funders | Funder number |
|---|---|
| Center for Nuclear Femtography | C2019-FEMT-002-05, C2-2020-FEMT-006 |
| Commonwealth of Virginia Equipment Trust Fund | ACI-1548562 |
| Consorzio Interuniversitario per il Calcolo Automatico dellItalia Nord-orientale | JLAB-THY-21-3469, Pra21-5389 |
| Pittsburgh Supercomputing Center | DE-AC05-00OR22725, DE-AC02-05CH11231 |
| National Science Foundation | ACI-1445606 |
| U.S. Department of Energy | DE-SC0011941, DE-FG02-04ER41302, DE-FG02-97ER41028 |
| Directorate for Computer and Information Science and Engineering | 1445606 |
| Office of Science | |
| Advanced Scientific Computing Research | |
| Nuclear Physics | DE-AC05-06OR23177 |
| Materials Research Institute, Pennsylvania State University | PHY-1626177 |
| Partnership for Advanced Computing in Europe AISBL |