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The analysis of the cluster environment is a valuable instrument toinvestigate the origin of AGN and star-forming galaxies gas fuelling andtrigger mechanisms. To this purpose, we present a detailed analysis of thepoint-like X-ray sources in the Bullet cluster field. Thanks to $\sim600$ ksChandra observations, we produced a catalogue of 381 X-ray point sources up toa distance of $\sim$1.5 virial radius and with flux limits$\sim1\times10^{-16}$ and $\sim8\times10^{-16}$ erg cm$^{-2}$ s$^{-1}$ in the0.5-2 keV and 2-10 keV bands, respectively. We found a strong (up to a factor1.5-2) and significant ($\ge$4$\sigma$) over-density in the full region studied$0.3R_{200}<R<1.5R_{200}$. We identified optical and infrared counterparts for$\sim$84% and $\sim$48% of the X-ray sources, respectively. We obtained newspectroscopic redshifts for 106 X-ray sources. Spectroscopic and photometricredshifts of optical and infrared sources have been also collected, and thesesources were used as ancillary samples. We find that the over-density in theregion $0.3R_{200}<R<R_{200}$ is likely due to X-ray AGN (mostly obscured) andstar-forming galaxies both associated to the cluster, while in the moreexternal region it is likely mostly due to background AGN. The fraction ofcluster galaxies hosting an X-ray detected AGN is 1.0$\pm$0.4$\%$, nearlyconstant with the radius, a fraction similar to that reported in other clustersof galaxies at similar redshift. The fraction of X-ray bright AGN(L$_{2-10keV}$$>$10$^{43}$ ergs s$^{-1}$) in the region $0.3R_{200}<R<R_{200}$is $0.5^{+0.6}_{-0.2}$$\%$, higher than that in other clusters at similarredshift and more similar to the AGN fraction in the field. Finally, thespatial distributions of AGN and star-forming galaxies, selected also thanks totheir infrared emission, appear similar, thus suggesting that both aretriggered by the same mechanism.

Triggering nuclear and galaxy activity in the Bullet cluster