Searching for axion dark matter decaying into photons: from radio to X-rays

by Elisa Todarello (Berkeley)

Wednesday 22 Apr 2026, 12:30 → 14:30 America/Los_Angeles

48/2-224 - Madrone (SLAC)

Axions and axion-like particles couple to photons through a distinctive two-photon vertex. This coupling allows for axion-photon conversion in an external magnetic field, a phenomenon at the base of a variety of current axion searches. Additionally, due to the same vertex, axions can also decay into two photons. In this talk, I will show how we can search for axion dark matter by looking for excess radiation resulting from axion decay within a narrow frequency band centered around half the unknown axion mass m. Depending on the value of m, the decay process is dominated by either spontaneous or stimulated decay, requiring corresponding adjustments in the search strategy.