Anisotropic Magnetized White Dwarfs: Unifying Under- and Overluminous Peculiar and Standard Type Ia Supernovae

Abstract

Abstract Ever since the observation of peculiar overluminous Type Ia supernovae (SNeIa), exploring possible violations of the canonical Chandrasekhar mass limit (CML) has become a pressing research area of modern astrophysics. Since its first detection in 2003, more than a dozen of peculiar overluminous SNeIa has been detected, but the true nature of the underlying progenitors is still under dispute. Furthermore there are also underluminous SNeIa whose progenitor masses appear to be well below the CML (sub-Chandrasekhar progenitors). These observations call into question how sacrosanct the CML is. We have shown recently in Paper I that the presence of a strong magnetic field, the anisotropy of dense matter, as well as the orientation of the magnetic field itself significantly influence the properties of neutron and quark stars. Here, we study these effects for white dwarfs (WDs), showing that their properties are also severely impacted. Most importantly, we arrive at a variety of mass–radius relations of WDs that accommodate sub- to super-Chandrasekhar mass limits. This urges caution when using WDs associated with SNeIa as standard candles.