Discontinuity and disorder: Explaining the luminosity bump in evolved stars

Discontinuity and disorder: Explaining the luminosity bump in evolved stars

Toward the end of their lives, low-mass stars undergo an abrupt dip in brightness, also known as the luminosity bump. While the endpoint of this bump is well understood, its onset has remained elusive. Now, in a paper published by The Astrophysical Journal Letters, Saskia Hekker, leader of the Theory and Observations of Stars group at the Heidelberg Institute for Theoretical Studies (HITS), finds that entropy is the key driver of the bump.