Fri·Jan 5, 2024Friday·January 5, 2024

1. 01*

   Shear viscosity of nucleonic matter

   Xian-Gai Deng🇨🇳 · De-Qing Fang🇨🇳 · Yu-Gang Ma🇨🇳

   The research status of the shear viscosity of nucleonic matter is reviewed. Some methods to calculate the shear viscosity of nucleonic matter are introduced, including mean free path, Green-Kubo, shear strain rate, Chapman-Enskog and relaxation time approximation. Based on these methods, results for infinite and finite nucleonic matter are discussed, which are attempts to investigate the universality of the ratio of shear viscosity over entropy density and transport characteristics like the liquid-gas phase transition in nucleonic matter. In addition, shear viscosity is also briefly discussed for the quantum chrodynamical matter produced in relativistic heavy-ion collisions.

   ↳ nucl-thnucl-exPPNP(2024)·24 citations
2. 02*

   Towards the determination of the 3-dimensional structure of the proton using lattice QCD simulations

   Constantia Alexandrou (Univ. of Cyprus & The Cyprus inst.)🇨🇾 · Simone Bacchio (The Cyprus Inst.)🇨🇾

   State-of-the-art lattice QCD simulations enable the evaluation of nucleon form factors and Mellin moments with controlled systematics, yielding results with unprecedented accuracy. At the same time, new theoretical approaches are allowing the direct computation of nucleon generalized parton distributions. We review recent lattice QCD results on these quantities that are paving the way for extracting a wealth of information on the 3-dimensional structure of the nucleon.

   ↳ hep-latnucl-exnucl-th0 citations
3. 03*

   Updated numerical study of transverse single-spin asymmetries in single-inclusive pion production from lepton-nucleon collisions

   Sophia Fitzgibbons🇺🇸 · Michel Malda🇺🇸 · Jacob Marsh🇺🇸 · Daniel Pitonyak🇺🇸 · Penn Smith🇺🇸

   We revisit the analysis of transverse single-spin asymmetries $A_N$ in lepton-nucleon scattering where only a single pion is detected in the final state, $\ell N^{\uparrow }\to hX$. This observable is the Electron-Ion Collider (EIC) analogue to $A_N$ in proton-proton collisions, $p^{\uparrow }p\to hX$, that has been studied intensely for decades, especially at the Relativistic Heavy Ion Collider (RHIC). We incorporate new theoretical developments in the collinear twist-3 framework and utilize recent extractions of (Sivers-like and Collins-like) quark-gluon-quark correlators in the numerical computations. We compare our calculations to HERMES measurements as well as make predictions for Jefferson Lab, COMPASS, and EIC kinematics. We further explore the role of next-to-leading order (NLO) corrections to the (twist-2) unpolarized cross section (denominator of $A_N$) and consider what can be deduced empirically about the potential numerical significance of the full NLO calculation of $A_N$ in this process. We consider sources of theoretical uncertainty in our predictions, which present potential opportunities then for future measurements to improve our understanding of $A_N$ and multi-parton correlations in hadrons.

   ↳ hep-phhep-exnucl-exnucl-thPLB(2024)·5 citations

* 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.