A NEW SPHERICALLY SYMMETRIC NEUTRON STAR MODEL EMBEDDING CLASS I IN DURGAPAL METRIC
DOI:
https://doi.org/10.55766/sujst-2024-02-e01814Keywords:
Anisotropy, Class I Reducibility, Durgapal Metric, Neutron Star, Spherically SymmetryAbstract
In this paper, we develop a novel spherically symmetric neutron star model by combining the two useful mathematical aspects of astrophysics, Karmakar’s condition and Durgapal metric for anisotropic stellar objects. We use Karmakar’s condition to embed a class I reducibility criteria in the model. The solutions are simplified by considering 𝒆𝝂=𝑩(𝟏+𝒙)𝟔, where 𝒙=𝑪𝒓𝟐, beyond the fifth model given by Durgapal. The model does not have the central singularity. The model well behaves for the realistic physical properties of the neutron stars. The energy density, the pressure in the radial direction, and the pressure in the tangential direction are positively finite and decrease from the center to the surface of the neutron stars. The redshift and the compression moduli are also positive finite. In the offered model, we take the values of the constants as 1.5760 ≤ A ≤ 2.295, 0.0602 ≤ B ≤ 0.5577, and 7.492 × 10-10 ≤ C ≤ 3.397 × 10-9 for the neutron stars EXO 1785-248, SMC X-1, Her X-1, 4U 1538-52, LMC X-4, and Cen X-3. The Buchdahl condition is well satisfied by the model.
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