Year: 2021
Type: article
Abstract: We present lattice QCD results for masses and magnetic polarizabilities of light and strange pseudoscalar mesons, chiral condensates, decay constants of neutral pion, and neutral kaon in the presence of background magnetic fields with $eB$ ranging up to around $3.35\text{ }\text{ }{\mathrm{GeV}}^{2}$ ($\ensuremath{\sim}70{M}_{\ensuremath{\pi}}^{2}$) in the vacuum. The computations were carried out in ($2+1$)-flavor QCD mostly on ${32}^{3}\ifmmode\times\else\texttimes\fi{}96$ lattices using the highly improved staggered quark action with ${M}_{\ensuremath{\pi}}\ensuremath{\approx}220\text{ }\text{ }\mathrm{MeV}$ at zero temperature. We find that the masses of neutral pseudoscalar mesons monotonously decrease as the magnetic field strength grows and then saturate at a nonzero value, while there exists a nonmonotonous behavior of charged pion and kaon masses in the magnetic field. We observe a $qB$ scaling of the up and down quark flavor components of neutral pion mass, neutral pion decay constant as well as the quark chiral condensates at $0.05\ensuremath{\lesssim}eB\ensuremath{\lesssim}3.35\text{ }\text{ }{\mathrm{GeV}}^{2}$. We show that the correction to the Gell-Mann-Oakes-Renner relation involving the neutral pion is less than 6% and the correction for the relation involving neutral kaon is less than 30% at $eB\ensuremath{\lesssim}3.35\text{ }\text{ }{\mathrm{GeV}}^{2}$. We also derive the Ward-Takahashi identities for QCD in the magnetic field in the continuum formulation including the relation between integrated neutral pseudoscalar meson correlators and chiral condensates.
Authors: H.-T. Ding, S.-T. Li, A. Tomiya, X.-D. Wang, Y. Zhang
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Awards: G3197473290, G6742395515, G8925070428
OpenAlex ID: W3046606554