Correlation of the 2-10 keV X-ray background with nearby galaxies
Abstract
Catalogues of several types of extragalactic objects have been cross-correlated with Ginga measurements of the X-ray background intensity. Some of these catalogues give rise to significant signals, meaning that either sources in them or some other sources clustered around them produce a fraction of the X-ray background. The significance of these results has been established using bootstrap and X-ray background simulations. An expression to infer the local X-ray emissivity from the cross-correlation signal is given and applied to two galaxy catalogues (UGC and IRAS) for which the signal is more significant (>95 per cent). Values of ~ 10^39 h erg s^-1 Mpc^-3 are obtained, implying that <= 30 per cent of the X-ray background could be produced by a non-evolving population of galaxies.
- Publication:
-
Advances in Space Research
- Pub Date:
- March 1995
- DOI:
- 10.1016/0273-1177(95)00056-K
- Bibcode:
- 1995AdSpR..16c.111C
- Keywords:
-
- Active Galactic Nuclei;
- Astronomical Catalogs;
- Background Radiation;
- Cross Correlation;
- Signal Processing;
- X Ray Astronomy;
- Data Correlation;
- Energy Spectra;
- Ginga Satellite;
- Goodness Of Fit;
- Statistical Analysis;
- X Ray Sources;
- Astronomy