Abstract
We present a class of solutions for a spherically symmetric anisotropic matter distribution in Vaidya and Tikekar spheroidal geometry. Making use of the Vaidya and Tikekar (VT) metric ansatz (J Astrophys Astron 3:325, 1982) for one of the metric functions \(g_{rr}\), we obtain the unknown metric function \(g_{tt}\) by utilizing the Karmakar’s embedding condition which makes the master equation tractable. The model parameters are fixed by utilizing the matching conditions of the interior spacetime and the exterior Schwarzschild solution at the boundary of the star where the radial pressure vanishes. The closed-form interior solution of the Einstein field equations thus obtained is shown to be capable of describing ultra-compact stellar objects where anisotropy might develop. The current estimated masses and radii of some other pulsars are utilized to show that the developed model meets all the requirements of a realistic star. The stability of the model is analyzed. The dependence of the curvature parameter K of the VT model, which characterizes a departure from homogeneous spherical distribution, is also investigated.
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Acknowledgements
RS and KC gratefully acknowledge support from the Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune, India, under its Visiting Research Associateship Programme. SD is thankful to the Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune, India, where a part of this work was carried out.
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Das, S., Sharma, R., Chakraborty, K. et al. Anisotropic compact stellar model of embedding class-I satisfying Karmarkar’s condition in Vaidya and Tikekar spheroidal geometry. Gen Relativ Gravit 52, 101 (2020). https://doi.org/10.1007/s10714-020-02753-4
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DOI: https://doi.org/10.1007/s10714-020-02753-4