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arXiv · 2002.12044

Parton distribution functions of $\Delta^+$ on the lattice

Yahui Chai·Yuan Li·Shicheng Xia·Constantia Alexandrou·Krzysztof Cichy·Martha Constantinou·Xu Feng·Kyriakos Hadjiyiannakou·Karl Jansen·Giannis Koutsou·Chuan Liu·Aurora Scapellato·Fernanda Steffens
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Abstract

We perform a first calculation for the unpolarized parton distribution function of the $\Delta^+$ baryon using lattice QCD simulations within the framework of Large Momentum Effective Theory. Two ensembles of $N_f=2+1+1$ twisted mass fermions are utilized with a pion mass of 270 MeV and 360 MeV, respectively. The baryon, which is treated as a stable single-particle state, is boosted with momentum $P_3$ with values $\{0.42,0.83,1.25\}$ GeV, and we utilize momentum smearing to improve the signal. The unpolarized parton distribution function of $\Delta^+$ is obtained using a non-perturbative renormalization and a one-loop formula for the matching, with encouraging precision. In particular, we compute the $\overline{d}(x)-\overline{u}(x)$ asymmetry and compare it with the same quantity in the nucleon, in a first attempt towards resolving the physical mechanism responsible for generating such asymmetry.

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Yahui Chai, Yuan Li, Shicheng Xia, Constantia Alexandrou, Krzysztof Cichy, Martha Constantinou, Xu Feng, Kyriakos Hadjiyiannakou, Karl Jansen, Giannis Koutsou, Chuan Liu, Aurora Scapellato, Fernanda Steffens. 2020-02-27. Parton distribution functions of $\Delta^+$ on the lattice. https://doi.org/10.1103/physrevd.102.014508

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