English

Quarkonium in non-zero isospin chemical potential environment at $T \simeq 0$

High Energy Physics - Lattice 2026-02-20 v1 Nuclear Theory

Abstract

We study how the isospin asymmetry affects quarkonium states in QCD at near zero temperature. Using lattice Non-Relativistic QCD formalism, we calculate bottom quark correlators in the gauge field ensembles generated with Nf=2+1N_f = 2 + 1 flavors of dynamical staggered quarks whose dynamics include the isospin chemical potential effect and then construct SS- and PP- wave quarkonium state correlators. From these quarkonium correlators, we consider the ratios of quarkonium correlators at non-zero isospin chemical potential to that at μIa=0.000\mu_I a = 0.000. Here, the gauge field ensemble with μIa=0.000,0.048,0.053,0.059,0.066,0.080,0.092\mu_I a = 0.000, 0.048, 0.053, 0.059, 0.066, 0.080, 0.092 and 0.1060.106 on a 323×4832^3 \times 48 lattice with non-zero isospin current strength λa=0.0010,0.0018,\lambda a = 0.0010, 0.0018, and 0.00360.0036, where mπ=135m_\pi = 135 MeV and a=0.1535a = 0.1535 fm from \cite{Brandt:2022hwy}, are used. Preliminary results suggest that for μIa=0.106\mu_I a = 0.106, the Upsilon mass gets heavier than the Upsilon mass in the vacuum and that below μIa=0.106\mu_I a = 0.106 the isospin asymmetry effect on the Upsilon mass is not monotonic.

Keywords

Cite

@article{arxiv.2602.17232,
  title  = {Quarkonium in non-zero isospin chemical potential environment at $T \simeq 0$},
  author = {Seyong Kim and Bastian B. Brandt and Gergely Endrődi},
  journal= {arXiv preprint arXiv:2602.17232},
  year   = {2026}
}

Comments

10 pages, 13 figures, 1 table, Proceedings of the 42nd International Symposium on Lattice Field Theory (Lattice 2025), TIFR Mumbai, India, 2025