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Impossibility of Spin Polarized States for Neutron Star / Proto-neutron Star Matter in $β$-Equilibrium Condition

Sutapa Ghosh·Soma Mandal·Somenath Chakrabarty
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Abstract

It is shown explicitly that a ferromagnetic transition of neutron star (NS) / proto-neutron star (PNS) matter in the $β$-equilibrium condition with $σ-ω-ρ$ exchange type of mean field approximation can actually occur if and only if the neutrinos remain trapped within the system, and perhaps it is also necessary for the neutrinos / anti-neutrinos to carry some finite non-zero mass. It is further shown that the electrons also play a significant role in this transition process. It is therefore, very much unlikely that such a transition of spin polarization can really take place in old neutron stars of very low temperature, whereas, the possibility of spontaneous ferromagnetic transition cannot be ruled out in a newly born PNS.

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Sutapa Ghosh, Soma Mandal, Somenath Chakrabarty. 2003-06-13. Impossibility of Spin Polarized States for Neutron Star / Proto-neutron Star Matter in $β$-Equilibrium Condition. https://doi.org/10.1142/s0217732303008867

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