arXiv subjects

O. A. Kochetkov

Publications and source records attributed to O. A. Kochetkov.

4 recordsLinked to original sources

arXiv2015

Magnetic polarizabilities of light mesons in $SU(3)$ lattice gauge theory

We investigate the masses (ground state energies) of neutral pseudoscalar and vector meson in $SU(3)$ lattice gauge theory in strong abelian magnetic field. The energy of $ρ^0$ meson with zero spin projection $s_z=0$ on the axis of the external magnetic field decreases, while the energies with non-zero spins $s_z=-1$ and $+1$ increase with the field. The energy of $π^0$ meson decrease as a function of the magnetic field. We calculated the magnetic polarizabilities of pseudoscalar and vector mesons for lattice volume $18^4$. For $ρ^0$ with spin $|s_z|=1$ and $π^0$ meson the extrapolations to zero lattice spacing have been done. We do not observe any evidence in favour of tachyonic mode existence.

hep-lat↗

arXiv2015

Deconfinement transition in two-flavour lattice QCD with dynamical overlap fermions

We study the deconfinement transition in two-flavour lattice QCD with dynamical overlap fermions. Our simulations have been carried out on a $16^3 \times 6$ lattice at a pion mass around 500 MeV with a special HMC algorithm without any approximation such as fixed topology. We consider several temperatures from 220 MeV which is close to the deconfinement to 280 MeV which is above it. The dependence of the Polyakov loop, the chiral condensate, the Dirac spectra and the connected part of chiral susceptibility on the inverse gauge coupling has been studied. Our data indicates that the transition point lies between $β= 7.6$ and $β= 8.1$, but a more precise determination is not possible with our present statistics.

hep-lat↗

arXiv2014

$ρ$ mesons in strong abelian magnetic field in SU(3) lattice gauge theory

We explore the masses of neutral and charged $ρ$ mesons in strong abelian magnetic field in $SU(3)$ gluodynamics. The behaviour of the ground state energy of these particles in the external magnetic field depends on its spin projection $s_z$ on the axis of external magnetic field. The masses of $ρ^0$ meson with $s_z=\pm 1$ increase with the field. The masses of $ρ^{\pm}$ mesons with zero spin also grow with the magnetic field. The ground state energies of $ρ^{-}$ meson with $s_z=-1$ and $ρ^{+}$ meson with $s_z=+1$ diminish as a function of the field, while the energies of $ρ^{+}$ meson with $s_z=-1$ and $ρ^{-}$ meson with $s_z=+1$ rise with the field value.

hep-lat↗

arXiv2014

Deconfinement transition in two-flavour lattice QCD with dynamical overlap fermions in an external magnetic field

We study the influence of an external magnetic field on the deconfinement transition in two-flavour lattice QCD with physical quark charges. We use dynamical overlap fermions without any approximation such as fixed topology and perform simulations on a $16^3 \times 6$ lattice and at a pion mass around $500MeV$. The pion mass (as well as the lattice spacing) was determined in independent runs on $12^3 \times 24$ lattices. We consider two temperatures, one of which is close to the deconfinement transition and one which is above. Within our limited statistics the dependence of the Polyakov loop and chiral condensate on the magnetic field supports the "inverse magnetic catalysis" scenario in which the transition temperature decreases as the field strength grows for temperature not to far above the critical temperature.

hep-lat↗