# The optically thick rotating magnetic wind from a massive white dwarf merger product

## TL;DR

This paper models the optically thick, rotating magnetic wind of a massive white dwarf merger product, explaining observed properties and predicting its future evolution and potential as a high-energy source.

## Contribution

It introduces a new wind solution model for a massive, magnetic white dwarf merger product, linking observed wind properties to the star's magnetic field, spin, and origin.

## Key findings

- The white dwarf has a mass of 1.1-1.3 solar masses.
- Magnetic field strength is estimated at (2-5)×10^7 G.
- The star's spin period is approximately 2-5 seconds.

## Abstract

WD J005311 is a newly identified white dwarf (WD) in a mid-infrared nebula. The spectroscopic observation indicates the existence of a neon-enriched carbon/oxygen wind with a terminal velocity of $v_{\infty,\rm obs}\sim 16,000\,\rm km\,s^{-1}$ and a mass loss rate of $\dot M_{\rm obs}\sim 3.5\times 10^{-6}\,M_\odot$ yr$^{-1}$. Here we consistently explain the properties of WD J005311 using a newly constructed wind solution, where the optically thick outflow is launched from the carbon burning shell on an oxygen-neon core and accelerated by the rotating magnetic field to become supersonic and unbound well below the photosphere. Our model implies that WD J005311 has a mass of $M_* \sim 1.1\mbox{-}1.3\,M_\odot$, a magnetic field of $B_* \sim (2\mbox{-}5)\times 10^7\,\rm G$, and a spin angular frequency of $\Omega \sim 0.2\mbox{-}0.5 \,\rm s^{-1}$. The large magnetic field and fast spin support the carbon-oxygen WD merger origin. WD J005311 will neither explode as a type Ia supernova nor collapse into a neutron star. If the wind continues to blow another few kyr, WD J005311 will spin down significantly and join to the known sequence of slowly-rotating magnetic WDs. Otherwise it may appear as a fast-spinning magnetic WD and could be a new high energy source.