Discovery of Beryllium in White Dwarfs Polluted by Planetesimal Accretion

TL;DR

This paper reports the first detection of beryllium in white dwarf stars, revealing unprecedented overabundance levels likely produced by spallation processes in planetary debris.

Contribution

It presents the first identification of beryllium in white dwarf spectra and suggests a new origin for Be via spallation in accreted planetary material.

Findings

First detection of Be in white dwarfs

Unprecedented Be overabundance observed

Be likely produced by spallation in planetary debris

Abstract

The element beryllium is detected for the first time in white dwarf stars. This discovery in the spectra of two helium-atmosphere white dwarfs was made possible only because of the remarkable overabundance of Be relative to all other elements, heavier than He, observed in these stars. The measured Be abundances, relative to chondritic, are by far the largest ever seen in any astronomical object. We anticipate that the Be in these accreted planetary bodies was produced by spallation of one or more of O, C, and N in a region of high fluence of particles of MeV or greater energy.