Pseudoscalar and vector meson form factors from lattice QCD

Abstract

We present a study of the pseudoscalar and vector meson form factors, calculated using the Fat-Link Irrelevant Clover (FLIC) action in the framework of Quenched Lattice QCD. Of particular interest is the determination of a negative quadrupole moment, indicating that the ρ meson is not spherically symmetric.

Determination of the properties of vector mesons in external magnetic field by quenched SU(3) lattice QCD

“…We have obtained the most accurate value g = 2.11 ± 0.01 for the finest lattice with the spacing a = 0.086 fm, the lattice volume 18 4 Our value of the ρ ± magnetic moment agrees with the other lattice predictions at nonzero pion masses [27,30,41]. The magnetic moment in pure gauge theory differs from the full 2+1 QCD result, its value is lower for approximately 5 − 10% for the same pion masses [30].…”

“…the prediction of the QCD sum rules 2.0 ± 0.4 [43] and the lattice results [27,41]. Any dependence of the g-factor on the strange quark mass has not been observed within the error range.…”

“…For example, in 2+1 full QCD the g-factor of the ρ ± meson is equal to 2.21 (8) at the physical point [30]. Quenched lattice theory predicts the value g = 2.25(0.34) in the chiral limit [24] and g = 2.20(0.15) at the lowest pion mass [27].…”

“…The magnetic polarizabilities of baryons have been obtained in full lattice QCD [8]. The magnetic moment of the ρ meson has been explored in [24][25][26][27][28][29][30].…”

The evolution of meson masses in a strong magnetic field

“…On the theoretical side the main directions of research in this area are the lattice studies [20,21]- [31], [32]- [43], the chiral Lagrangians with MF [44]- [50,51], effective hadron Lagrangians [1,2,[52][53][54][55][56], [57]- [60], and recently developed path integral Hamiltonians (PIH) [62]- [68], and the chiral Lagrangian with quark degrees of freedom [69].…”