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arXiv · 1912.00075

Triggering nuclear and galaxy activity in the Bullet cluster

S. Puccetti·F. Fiore·A. Bongiorno·K. Boutsia·R. Fassbender·M. Verdugo
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Abstract

The analysis of the cluster environment is a valuable instrument to investigate the origin of AGN and star-forming galaxies gas fuelling and trigger mechanisms. To this purpose, we present a detailed analysis of the point-like X-ray sources in the Bullet cluster field. Thanks to $\sim600$ ks Chandra observations, we produced a catalogue of 381 X-ray point sources up to a distance of $\sim$1.5 virial radius and with flux limits $\sim1\times10^{-16}$ and $\sim8\times10^{-16}$ erg cm$^{-2}$ s$^{-1}$ in the 0.5-2 keV and 2-10 keV bands, respectively. We found a strong (up to a factor 1.5-2) and significant ($\ge$4$\sigma$) over-density in the full region studied $0.3R_{200} $10$^{43}$ ergs s$^{-1}$) in the region $0.3R_{200}<R<R_{200}$ is $0.5^{+0.6}_{-0.2}$$\%$, higher than that in other clusters at similar redshift and more similar to the AGN fraction in the field. Finally, the spatial distributions of AGN and star-forming galaxies, selected also thanks to their infrared emission, appear similar, thus suggesting that both are triggered by the same mechanism.

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S. Puccetti, F. Fiore, A. Bongiorno, K. Boutsia, R. Fassbender, M. Verdugo. 2019-11-29. Triggering nuclear and galaxy activity in the Bullet cluster. https://doi.org/10.1051/0004-6361%2F201833601

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