Most old distant radio galaxies should be extended X-ray sources due to inverse Compton scattering of Cosmic Microwave Background (CMB) photons. Such sources can be an important component in X-ray surveys for high redshift clusters, due to the increase with redshift of both the CMB energy density and the radio source number density. We estimate a lower limit to the space density of such sources and show that inverse Compton scattered emission may dominate above redshifts of one and X-ray luminosities of 10^44 erg/s, with a space density of radio galaxies > 10^-8 Mpc^-3. The X-ray sources may last longer than the radio emission and so need not be associated with what is seen to be a currently active radio galaxy.
Extended X-ray emission at high redshifts: radio galaxies vs clusters / Celotti, Anna Lisa; Fabian, A. C.. - In: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY. - ISSN 0035-8711. - 353:2(2004), pp. 523-528. [10.1111/j.1365-2966.2004.08085.x]
Extended X-ray emission at high redshifts: radio galaxies vs clusters
Celotti, Anna Lisa;
2004-01-01
Abstract
Most old distant radio galaxies should be extended X-ray sources due to inverse Compton scattering of Cosmic Microwave Background (CMB) photons. Such sources can be an important component in X-ray surveys for high redshift clusters, due to the increase with redshift of both the CMB energy density and the radio source number density. We estimate a lower limit to the space density of such sources and show that inverse Compton scattered emission may dominate above redshifts of one and X-ray luminosities of 10^44 erg/s, with a space density of radio galaxies > 10^-8 Mpc^-3. The X-ray sources may last longer than the radio emission and so need not be associated with what is seen to be a currently active radio galaxy.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
