Sinha, Monika

The existence of compact stars with high mass (> 2 M⊙ ) raises the possibility of the appearance of heavy baryons at high-density regimes.With this possibility, we study the effect of a strong magnetic field on the matter composed of baryon-octet and Δ -resonances under strong magnetic fields.The functionals in the hyperonic sector are constrained by the Λ, Ξ- hypernuclei data from terrestrial experiments.Δ -resonance sector is constrained by studies of their scattering off nuclei and heavy-ion collisions.The main effect of the magnetic field is shown to be the oscillations of various matter properties, viz., particle populations and Dirac effective mass with density resulting from the occupation of the Landau level by charged fermions in strong magnetic fields.

In this work, we study the effect of (anti)kaon condensation on the properties of compact stars that develop hypernuclear cores with and without an admixture of Δ-resonances. We work within the covariant density functional theory with the parameters adjusted to K-atomic and kaon-nucleon scattering data in the kaonic sector. The density-dependent parameters in the hyperonic sector are adjusted to the data on Λ and Ξ- hypernuclei data. The Δ-resonance couplings are tuned to the data obtained from their scattering off nuclei and heavy-ion collision experiments. We find that (anti)kaon condensate leads to a softening of the equation of state and lower maximum masses of compact stars than in the absence of the condensate. Both the K- and K̄0 condensations occur through a second-order phase transition, which implies no mixed-phase formation. For large values of (anti)kaon and Δ-resonance potentials in symmetric nuclear matter, we observe that condensation leads to an extinction of Ξ-,0 hyperons. We also investigate the influence of inclusion of additional hidden-strangeness σ∗ meson in the functional and find that it leads to a substantial softening of the equation of state and delay in the onset of (anti)kaons.

We construct a new equation of state for the baryonic matter under an intense magnetic field within the framework of covariant density functional theory. The composition of matter includes hyperons as well as (Formula presented.) -resonances. The extension of the nucleonic functional to the hypernuclear sector is constrained by the experimental data on (Formula presented.) and (Formula presented.) -hypernuclei. We find that the equation of state stiffens with the inclusion of the magnetic field, which increases the maximum mass of neutron star compared to the non-magnetic case. In addition, the strangeness fraction in the matter is enhanced. Several observables, like the Dirac effective mass, particle abundances, etc. show typical oscillatory behavior as a function of the magnetic field and/or density which is traced back to the occupation pattern of Landau levels.