Open AccessMap of the Galaxy in the 6.7‐keV emission line
Author(s) -
Revnivtsev M.,
Molkov S.,
Sazonov S.
Publication year - 2006
Publication title -
monthly notices of the royal astronomical society: letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.067
H-Index - 122
eISSN - 1745-3933
pISSN - 1745-3925
DOI - 10.1111/j.1745-3933.2006.00233.x
Subject(s) - physics , astrophysics , surface brightness , bulge , galaxy , brightness , line (geometry) , astronomy , emission spectrum , infrared , cosmic infrared background , spectral line , optics , geometry , mathematics , cosmic microwave background , anisotropy
We study the two‐dimensional surface brightness distribution of the Galactic X‐ray background emission outside the central degree around Sgr A* in the 6.7‐keV line as measured by the Proportional Counter Array spectrometer of the Rossi X‐ray Timing Explorer observatory. The use of the emission line instead of continuum (3–20 keV) radiation and application of time‐variability filtering to the long data set allows us to strongly suppress the contamination of the Galactic ridge X‐ray emission (GRXE) map by bright point‐sources. The surface brightness in the 6.7‐keV line demonstrates very good correspondence with the near‐infrared surface brightness over the whole Galaxy, supporting the notion that the GRXE consists mostly of integrated emission from weak Galactic X‐ray sources. We find compatible linear correlations between near‐infrared and 6.7‐keV surface brightness for the bulge and disc of the Galaxy. This indicates that the populations of weak X‐ray sources making up the GRXE in the disc and in the bulge are not significantly different.