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arXiv · 1301.5965

New mass limit for white dwarfs: super-Chandrasekhar type Ia supernova as a new standard candle

Upasana Das·Banibrata Mukhopadhyay
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Abstract

Type Ia supernovae, sparked off by exploding white dwarfs of mass close to Chandrasekhar limit, play the key role to understand the expansion rate of universe. However, recent observations of several peculiar type Ia supernovae argue for its progenitor mass to be significantly super-Chandrasekhar. We show that strongly magnetized white dwarfs not only can violate the Chandrasekhar mass limit significantly, but exhibit a different mass limit. We establish from foundational level that the generic mass limit of white dwarfs is 2.58 solar mass. This explains the origin of over-luminous peculiar type Ia supernovae. Our finding further argues for a possible second standard candle, which has many far reaching implications, including a possible reconsideration of the expansion history of the universe.

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Upasana Das, Banibrata Mukhopadhyay. 2013-01-25. New mass limit for white dwarfs: super-Chandrasekhar type Ia supernova as a new standard candle. https://doi.org/10.1103/physrevlett.110.071102

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