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arXiv · 2201.00067

Nucleon isovector momentum fraction, helicity and transversity moment using Lattice QCD

Santanu Mondal·Tanmoy Bhattacharya·Rajan Gupta·Bálint Joó·Huey-Wen Lin·Sungwoo Park·Frank Winter·Boram Yoon
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Abstract

We present our recent high precision calculations (Phys. Rev. D102 (2020) no.5, 054512 and JHEP 04 (2021) 044, JHEP 21 (2020) 004) of the first moment of nucleon isovector polarized, unpolarized and transversity distributions, i.e., momentum fraction, helicity and transversity moment, respectively. We use the standard method for the calculation of these moments (via matrix elements of twist two operators), and carry out a detailed analysis of the sources of systematic uncertainty, in particular of excited state contributions. Our calculations have been performed using two different lattice setups (Clover-on-HISQ and Clover-on-Clover), each with several ensembles. They give consistent results that are in agreement with global fit analyses.

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Santanu Mondal, Tanmoy Bhattacharya, Rajan Gupta, Bálint Joó, Huey-Wen Lin, Sungwoo Park, Frank Winter, Boram Yoon. 2021-12-31. Nucleon isovector momentum fraction, helicity and transversity moment using Lattice QCD. https://arxiv.org/abs/2201.00067

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