Speaker
Mr
Nicholas Jennings
(University of Oxford)
Description
Axion-like particles (ALPs) can induce localised oscillatory modulations in the spectra of photon sources passing through astrophysical magnetic fields. Ultra-deep \emph{Chandra} observations of the Perseus cluster contain over $5 \times 10^5$ counts from the central NGC1275 AGN, and represent an extraordinary dataset for ALP searches. In this talk I will describe how we used these to search for spectral irregularities from the AGN. No irregularities were found at the ~30% level, allowing us to place leading constraints on the ALP-photon mixing parameter $g_{a\gamma\gamma} \simeq 1.5 - 3.5 \times 10^{-12} {\rm GeV}^{-1}$ for $m_a \lesssim 10^{-12} {\rm eV}$, depending on the magnetic field realisation along the line of sight. I also discuss prospects for improving these bounds, with the ATHENA X-ray Observatory, due for launch in 2028.
Primary authors
Ms
Francesca Day
(University of Oxford)
Dr
Francesco Muia
(University of Oxford)
Prof.
Joseph Conlon
(University of Oxford)
Prof.
Marcus Berg
(Karlstad University)
Dr
Markus Rummel
(Perimeter Institute)
Mr
Nicholas Jennings
(University of Oxford)
Dr
Sven Krippendorf
(University of Oxford)
