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arXiv · 1712.08313

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

Linhan Chen·Joseph P. Conlon
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Abstract

If axion-like particles (ALPs) exist, photons can convert to ALPs on passage through regions containing magnetic fields. The magnetised intracluster medium of large galaxy clusters provides a region that is highly efficient at ALP-photon conversion. X-ray observations of Active Galactic Nuclei (AGNs) located within galaxy clusters can be used to search for and constrain ALPs, as photon-ALP conversion would lead to energy-dependent quasi-sinusoidal modulations in the X-ray spectrum of an AGN. We use Chandra observations of the central AGN of the Perseus Cluster, NGC1275, to place bounds on massive ALPs up to m_a ~ 10^-11 eV, extending previous work that used this dataset to constrain massless ALPs.

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Linhan Chen, Joseph P. Conlon. 2017-12-22. Constraints on Massive Axion-Like Particles from X-ray Observations of NGC1275. https://doi.org/10.1093/mnras%2Fsty1591

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