Modified Einstein's gravity to probe the sub- and super-Chandrasekhar limiting mass white dwarfs: a new perspective to unify under- and over-luminous type la supernovae

Kalita, Surajit and Mukhopadhyay, Banibrata (2018) Modified Einstein's gravity to probe the sub- and super-Chandrasekhar limiting mass white dwarfs: a new perspective to unify under- and over-luminous type la supernovae. In: JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS (9).

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Abstract

Type Ia supernovae (SNeIa), used as one of the standard candles in astrophysics, are believed to form when the mass of the white dwarf approaches Chandrasekhar mass limit. However, observations in last few decades detected some peculiar SNeIa, which are predicted to be originating from white dwarfs of mass much less than the Chandrasekhar mass limit or much higher than it. Although the unification of these two sub-classes of SNeIa was attempted earlier by our group, in this work, we, for the first time, explain this phenomenon in terms of just one property of the white dwarf which is its central density. Thereby we do not vary the fundamental parameters of the underlying gravity model in the contrary to the earlier attempt. We effectively consider higher order corrections to the Starobinsky- f (R) gravity model to reveal the unification. We show that the limiting mass of a white dwarf is similar to M-circle dot for central density rho(c)similar to 1.4 x 10(8) g/cc, while it is similar to 2.8M(circle dot) for rho(c) similar to 1.6 x 10(10) g/cc under the same model parameters. We further confirm that these models are viable with respect to the solar system test. This perhaps enlightens very strongly the long standing puzzle lying with the predicted variation of progenitor mass in SNeIa.

Item Type:	Journal Article
Publication:	JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
Publisher:	IOP PUBLISHING LTD
Additional Information:	Copy right for this article belong to IOP PUBLISHING LTD, TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
Keywords:	modified gravity; white and brown dwarfs; astrophysical fluid dynamics; supernovas
Department/Centre:	Division of Physical & Mathematical Sciences > Physics
Date Deposited:	26 Sep 2018 15:27
Last Modified:	26 Sep 2018 15:27
URI:	http://eprints.iisc.ac.in/id/eprint/60741

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