EDP Sciences
Free access
Volume 444, Number 2, December III 2005
Page(s) 381 - 385
Section Extragalactic astronomy
DOI http://dx.doi.org/10.1051/0004-6361:20042526

A&A 444, 381-385 (2005)
DOI: 10.1051/0004-6361:20042526

Intensity of the cosmic X-ray backgound from HEAO1/A2 experiment

M. Revnivtsev1, 2, M. Gilfanov1, 2, K. Jahoda3 and R. Sunyaev1, 2

1  Max-Planck-Institute für Astrophysik, Karl-Schwarzschild-Str. 1, 85740 Garching bei München, Germany
    e-mail: mikej@mpa-garching.mpg.de
2  Space Research Institute, Russian Academy of Sciences, Profsoyuznaya 84/32, 117810 Moscow, Russia
3  Laboratory for High Energy Astrophysics, Code 662, Goddard Space Flight Center, Greenbelt, MD 20771, USA

(Received 13 December 2004 / Accepted 4 August 2005 )

We reanalyze data of HEAO1/A2 - the Cosmic X-ray Experiment - in order to repeat the measurements of the cosmic X-ray background (CXB) intensity and accurately compare this value with other measurements of the CXB. We used the data of MED, HED1, and HED3 detectors in scan mode, which allowed us to measure effective solid angles and effective areas of detectors self consistently, in the same mode as the CXB intensity was measured. We found that the average value of the CXB intensity is $1.96\pm0.10 \times 10^{-11}$ erg s-1 cm-2 deg-2 in the energy band 2-10 keV, or $9.7\pm0.5$ phot s-1 cm-2 at 1 keV assuming the power law spectral shape with photon index $\Gamma=1.4$ in this energy band. We compare the obtained measurements with those obtained by different instruments over the past few decades.

Key words: cosmology: observations -- X-rays: general

SIMBAD Objects

© ESO 2005