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arXiv · 1605.01043

Constraints on Axion-Like Particles from X-ray Observations of NGC1275

Marcus Berg·Joseph P. Conlon·Francesca Day·Nicholas Jennings·Sven Krippendorf·Andrew J. Powell·Markus Rummel
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Abstract

Axion-like particles (ALPs) can induce localised oscillatory modulations in the spectra of photon sources passing through astrophysical magnetic fields. Ultra-deep Chandra observations of the Perseus cluster contain over $5 \times 10^5$ counts from the AGN of the central cluster galaxy NGC1275, and represent a dataset of extraordinary quality for ALP searches. We use this dataset to search for X-ray spectral irregularities from the AGN. The absence of irregularities at the O(30%) level allows us to place leading constraints on the ALP-photon mixing parameter $g_{a\gamma\gamma} \lesssim 1.4 - 4.0 \times 10^{-12} {\rm GeV}^{-1}$ for $m_a \lesssim 10^{-12}$ eV, depending on assumptions on the magnetic field realisation along the line of sight.

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Marcus Berg, Joseph P. Conlon, Francesca Day, Nicholas Jennings, Sven Krippendorf, Andrew J. Powell, Markus Rummel. 2016-05-03. Constraints on Axion-Like Particles from X-ray Observations of NGC1275. https://doi.org/10.3847/1538-4357%2Faa8b16

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