[JC] The 511 keV Gamma-Ray Echo from Particle Decays in Supernovae

by Chui-Fan Kong

Thursday 30 Apr 2026, 15:00 → 16:00 Asia/Seoul

CTPU seminar room (IBS)

In this talk, I will discuss the recent paper (arXiv:2511.14857), “511 keV Gamma-Ray Echo from Particle Decays in Supernovae.” The work sets projected constraints on the axion–photon coupling using the 511 keV signal produced in the supernova envelope.

I will first introduce the physical picture, including axion production and decay, positron production, and positronium formation. I will then show how the constraints are derived from the ALP-induced 511 keV signal, along with the treatment of backgrounds.