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Register a new userSetting nonperturbative uncertainties on finite-temperature properties of neutron matter
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Arianna Carbone
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We present an error band on neutron matter properties at finite temperature (finite-T) which comprehends uncertainties on the nuclear interaction, the many-body method convergence, and the thermodynamical consistency of the approach. This study provides nonperturbative predictions for finite-T neutron matter employing chiral interactions which are selected on the basis of their performance in both finite nuclei and infinite matter at zero temperature. Since proper theoretical uncertainties at finite-T are still generally lacking, the band provided here represents a first step towards setting first-principles constraints on thermal aspects of the nuclear matter equation of state.
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We investigate the $f$-mode oscillation of the dark matter admixed hyperon star within the relativistic Cowling approximation. The macroscopic properties are calculated with the relativistic mean-field (RMF) equation of states by assuming that the dark matter particles are inside it. The coupling constants between hyperons and scalar mesons are fixed by fitting with hyperon potential depth, while for hyperons and vector mesons, we use SU(6) symmetry group method. The $f$-mode oscillation frequencies (only for $l=2$) are calculated with four different neutron star equation of states. We also check the effects of hyperons/dark matter and hyperons with dark matter EOSs on the $f$-mode oscillations varying with different astrophysical quantities such as mass ($M$), radius ($R$), compactness ($M/R$), surface red-shift ($Z_s$), average density ($bar{rho}$), dimensionless tidal deformability ($Lambda$) of the neutron star. Some significant changes have been seen on the $f$-mode frequencies with and without hyperons/dark matter or hyperons+dark matter. Substantial correlations are observed between canonical frequency and $Lambda$ ($f_{1.4}-Lambda_{1.4}$) and maximum frequency and canonical $Lambda$ ( $f_{max}-Lambda_{1.4}$)
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