GRMHD formulation of highly super-Chandrasekhar magnetized white dwarfs: stable configurations of non-spherical white dwarfs

TL;DR

This paper uses GRMHD simulations to demonstrate the existence of stable, highly magnetized super-Chandrasekhar white dwarfs with masses exceeding 3 solar masses, which could explain certain supernovae.

Contribution

It provides the first full-scale GRMHD numerical analysis confirming stable super-Chandrasekhar white dwarfs with different magnetic field geometries.

Findings

White dwarfs can exceed 3 solar masses with strong magnetic fields.

Polarity of magnetic fields influences star shape: oblate with poloidal, prolate with toroidal.

Stable configurations depend on magnetic field geometry.

Abstract

The topic of magnetized super-Chandrasekhar white dwarfs is in the limelight, particularly in the last few years, since our proposal of their existence. By full-scale general relativistic magnetohydrodynamic (GRMHD) numerical analysis, we confirm in this work the existence of stable, highly magnetized, significantly super-Chandrasekhar white dwarfs with mass more than 3 solar mass. While a poloidal field geometry renders the white dwarfs oblate, a toroidal field makes them prolate retaining an overall quasi-spherical shape, as speculated in our earlier work. These white dwarfs are expected to serve as the progenitors of over-luminous type Ia supernovae.