The recent discoveries of massive neutron stars, such as PSR J0348 + 0432 and PSR J1614 − 2230, have raised questions about the existence of exotic matter such as hyperons in the neutron star core. The validity of many established equations of states (EoS's) like the GM1 and FSUGold are also questioned. We investigate the existence of hyperonic matter in the central regions of massive neutron stars using Relativistic Mean Field (RMF) theory with the recently proposed IUFSU model. The IUFSU model is extended by including hyperons to study the neutron star in β equilibrium. The effect of different hyperonic potentials, namely Σ and Ξ potentials, on the EoS and hence the maximum mass of neutron stars has been studied. We have also considered the effect of stellar rotation since the observed massive stars are pulsars. It has been found that a maximum mass of 1.93M⊙, which is within the 3σ limit of the observed mass of PSR J0348 + 0432, can be obtained for rotating stars, with certain choices of the hyperonic potentials. The said star contains a fair amount of hyperons near the core.

Hypernuclei have been studied within the framework of Relativistic Mean Field theory. The force FSU Gold has been extended to include hyperons. The effective hyperon-nucleon and nucleon-nucleon interactions have been obtained by fitting experimental energies in a number of hypernuclei over a wide range of mass. Calculations successfully describe various features including hyperon separation energy and single particle spectra of single-Λ hypernuclei throughout the periodic table. We also extend this formalism to double-Λ hypernuclei. FormalismRMF calculations have been able to explain different features of stable and exotic nuclei like ground state binding energy, deformation, radius, exited states, spinorbit splitting, neutron halo etc. [26] There are a number of different Lagrangian densities as well as a number of different parametrization. In the present work the FSU Gold Lagrangian density has been employed. [25] While similar in spirit

Neutron and proton driplines of single-Λ and double-Λ hypernuclei, Ξ − hypernuclei as well as normal nuclei are studied within a relativistic mean field approach using an extended form of the FSU Gold Lagrangian density. Hyperons are found to produce bound nuclei beyond the normal nuclear driplines. Radii are found to decrease in hypernuclei near the driplines, in line with observations in light Λ hypernuclei near the stability valley. The inclusion of a Ξ − introduces a much larger change in radii than one or more Λ's.

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