Origin of quickest white dwarfs within the galaxy linked to supernova explosions

In a breakthrough examine published in Nature Astronomy, researchers have found a brand new origin for a number of the quickest stars ever noticed: hypervelocity white dwarfs—compact stellar remnants hurtling via house sooner than 2000 km/s.

Led by Dr. Hila Glanz of the Technion—Israel Institute of Technology, the worldwide workforce carried out state-of-the-art three-dimensional hydrodynamic simulations of a merger between two uncommon hybrid helium–carbon–oxygen white dwarfs. The outcomes reveal a dramatic sequence of occasions: because the lighter star is partially disrupted, the heavier one undergoes a double-detonation explosion, slingshotting the surviving remnants of its companion into house at hypervelocity speeds exceeding 2,000 kilometers per second—quick sufficient to flee the gravitational grip of the Milky Way.

“This is the first time we’ve seen a clean pathway where the remnants of a white dwarf merger can be launched at hypervelocity, with properties matching the hot, faint white dwarfs we observe in the halo,” mentioned Dr. Glanz. “This solves the mystery about the origin of these stellar runaways—and also opens up a new channel for faint and peculiar Type Ia supernovae.”

Unlike beforehand proposed situations, the brand new mannequin accounts for each the intense velocities and strange temperatures and brightness of recognized HVWDs, comparable to the celebrities J0546 and J0927. It additionally affords perception into underluminous thermonuclear explosions, that are essential instruments for measuring the universe’s growth and for understanding how parts are shaped in galaxies.

“This discovery doesn’t just help us understand hypervelocity stars—it gives us a window into new kinds of stellar explosions,” mentioned co-author Prof. Hagai Perets, additionally of Technion.

The examine was performed by researchers from the Technion, Universität Potsdam, and the Max Planck Institute for Astrophysics, combining high-performance simulations with new theoretical modeling.

The work has implications for upcoming transient surveys and Gaia knowledge releases, which can uncover extra of those elusive stellar cannonballs flying via the galaxy.