Magnetic-field dependence of the QCD electric screening mass parameter through g4 in hot and dense matter
Abstract
A constant magnetic field modifies the hard electric screening sector of hot and dense QCD and generates a directional splitting at 𝒪(g4). We determine the strict-hard screening pole through g4 for three massless flavors with physical u,d,s charges, retaining the full eB/T2 dependence without a weak- or strong-field expansion. The shifted-frequency construction used for the two-loop exchange contribution is a background-field Feynman-gauge curvature; we derive and apply its local conversion to the ordinary Feynman-gauge self-energy before assembling the screening pole. The leading magnetic shift is isotropic, while the g4 directional splitting arises from the one-loop anisotropic kinetic normalization; the symmetry-allowed finite-density A0F12 mixing is numerically small over the studied range for physical u,d,s charges. For μ/T=0 and $1$, the magnetic g4 coefficient is positive over 0≤ eB/T2≤4 and is strongly reduced by density. Extending the calculation to 0≤μ/T≤2 at eB/T2=1 and $4$ reveals sign reversals of both the leading magnetic coefficient and the directional splitting at sufficiently large density. The zero-field limit reproduces the Braaten-Nieto result and its finite-density extension by Vuorinen. The running coupling used only for the phenomenological magnetic mass shift is chosen independently of B, so that all magnetic-field dependence through g4 resides in the calculated coefficients.
Related
- Study of Λ CP Asymmetry Parameter and Electric Dipole Moment at the Super Tau-Charm Facility
- Parameter dependence of the mapping of the mean-field Ising model onto QCD in the first-order phase transition regime
- Double Parton Distributions in the nucleon: Lattice parameter dependence
- Remarks on the Parameter Dependence of QCD2A
- Beyond gauge-parameter dependence: Further evidence for asymptotic safety in Scalar-Tensor theories
BibTeX
@misc{haque2026magneticfield,
title = {{Magnetic-field dependence of the QCD electric screening mass parameter through $g^4$ in hot and dense matter}},
author = {Najmul Haque},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.28437},
eprint = {2610.28437},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.28437},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Magnetic-field dependence of the QCD electric screening mass parameter through g^4 in hot and dense matter
AU - Najmul Haque
PY - 2026
DA - 2026/10/20
PB - arXiv
DO - 10.48550/arxiv.2610.28437
UR - https://arxiv.org/abs/2610.28437
AB - A constant magnetic field modifies the hard electric screening sector of hot and dense QCD and generates a directional splitting at 𝒪(g^4). We determine the strict-hard screening pole through g^4 for three massless flavors with physical u,d,s charges, retaining the full eB/T^2 dependence without a weak- or strong-field expansion. The shifted-frequency construction used for the two-loop exchange contribution is a background-field Feynman-gauge curvature; we derive and apply its local conversion to the ordinary Feynman-gauge self-energy before assembling the screening pole. The leading magnetic shift is isotropic, while the g^4 directional splitting arises from the one-loop anisotropic kinetic normalization; the symmetry-allowed finite-density A_0F_12 mixing is numerically small over the studied range for physical u,d,s charges. For μ/T=0 and $1$, the magnetic g^4 coefficient is positive over 0≤ eB/T^2≤4 and is strongly reduced by density. Extending the calculation to 0≤μ/T≤2 at eB/T^2=1 and $4$ reveals sign reversals of both the leading magnetic coefficient and the directional splitting at sufficiently large density. The zero-field limit reproduces the Braaten-Nieto result and its finite-density extension by Vuorinen. The running coupling used only for the phenomenological magnetic mass shift is chosen independently of B, so that all magnetic-field dependence through g^4 resides in the calculated coefficients.
ER -