Abstract
We present here the analysis of X-ray point sources detected in several observations available in the XMM-Newton public archive. We focused, in particular, on energies below 1 keV, which are of particular relevance to the understanding of the diffuse X-ray background (DXB). The average field of all the exposures is 0.09deg-2. We reached an average flux sensitivity of 5.8 × 10-16ergs-1cm-2 in the soft band (0.5-2.0 keV) and 2.5 × 10-16ergs-1cm-2 in the very soft band (0.4-0.6 keV). In this paper, we discuss the log N-log S results, the contribution to the integrated X-ray sky flux, and the properties of the cumulative spectrum from all sources. In particular, we found an excess flux at around 0.5 keV in the composite spectrum of faint sources. The excess seems to be a general property of all the fields observed suggesting an additional class of weak sources is contributing to the X-ray emission at these energies. Combining our results with previous investigations, we have also quantified the contribution of the individual components of the DXB in the 3/4 keV band.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 270-276 |
| Number of pages | 7 |
| Journal | Astrophysical Journal |
| Volume | 702 |
| Issue number | 1 |
| DOIs | |
| State | Published - 2009 |
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Keywords
- Diffuse background
- X-rays
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Space and Planetary Science
- Astronomy and Astrophysics
Cite this
Contribution of unresolved point sources to the diffuse x-ray background below 1 keV. / Gupta, A.; Galeazzi, Massimiliano.
In: Astrophysical Journal, Vol. 702, No. 1, 2009, p. 270-276.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Contribution of unresolved point sources to the diffuse x-ray background below 1 keV
AU - Gupta, A.
AU - Galeazzi, Massimiliano
PY - 2009
Y1 - 2009
N2 - We present here the analysis of X-ray point sources detected in several observations available in the XMM-Newton public archive. We focused, in particular, on energies below 1 keV, which are of particular relevance to the understanding of the diffuse X-ray background (DXB). The average field of all the exposures is 0.09deg-2. We reached an average flux sensitivity of 5.8 × 10-16ergs-1cm-2 in the soft band (0.5-2.0 keV) and 2.5 × 10-16ergs-1cm-2 in the very soft band (0.4-0.6 keV). In this paper, we discuss the log N-log S results, the contribution to the integrated X-ray sky flux, and the properties of the cumulative spectrum from all sources. In particular, we found an excess flux at around 0.5 keV in the composite spectrum of faint sources. The excess seems to be a general property of all the fields observed suggesting an additional class of weak sources is contributing to the X-ray emission at these energies. Combining our results with previous investigations, we have also quantified the contribution of the individual components of the DXB in the 3/4 keV band.
AB - We present here the analysis of X-ray point sources detected in several observations available in the XMM-Newton public archive. We focused, in particular, on energies below 1 keV, which are of particular relevance to the understanding of the diffuse X-ray background (DXB). The average field of all the exposures is 0.09deg-2. We reached an average flux sensitivity of 5.8 × 10-16ergs-1cm-2 in the soft band (0.5-2.0 keV) and 2.5 × 10-16ergs-1cm-2 in the very soft band (0.4-0.6 keV). In this paper, we discuss the log N-log S results, the contribution to the integrated X-ray sky flux, and the properties of the cumulative spectrum from all sources. In particular, we found an excess flux at around 0.5 keV in the composite spectrum of faint sources. The excess seems to be a general property of all the fields observed suggesting an additional class of weak sources is contributing to the X-ray emission at these energies. Combining our results with previous investigations, we have also quantified the contribution of the individual components of the DXB in the 3/4 keV band.
KW - Diffuse background
KW - X-rays
UR - http://www.scopus.com/inward/record.url?scp=70449836158&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=70449836158&partnerID=8YFLogxK
U2 - 10.1088/0004-637X/702/1/270
DO - 10.1088/0004-637X/702/1/270
M3 - Article
AN - SCOPUS:70449836158
VL - 702
SP - 270
EP - 276
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 1
ER -