14 years of the INTEGRAL Galactic hard X-ray survey
INTEGRAL has made yet another step forward to complete our knowledge
about the population of hard X-ray sources of our Galaxy. Using the
latest sky maps comprising 14 years of data acquired with the IBIS
telescope onboard INTEGRAL, Roman Krivonos with his colleagues at the
Space Research Institute (IKI) in Moscow have reported on 72 hard X-ray
sources not known to previous INTEGRAL surveys. The nature of most of
them is unknown, opening the possibility of new discoveries.
The improved 14-year sensitivity of the INTEGRAL survey allows us to
extend the horizon of the accessible volume of the Galaxy in hard X-rays.
The imaginary face-on view of the Milky Way shown here illustrates the
distance out to which INTEGRAL can detect sources of given luminosity
(0.5 - 2)x1035 erg/s in the 17-60 keV hard X-ray band (solid
lines), in comparison with the previous survey based on the 9-year exposure
(dotted lines;
Krivonos et al., 2012, A&A 545, A27).
Red, orange and yellow contours correspond to luminosities of 2×1035,
1035 and 5×1034 erg/s, respectively.
We can now probe deeper into the Galactic center for weak sources, and
cover most of the Galactic stellar mass for bright distant objects located
at the far end of the Galaxy.
R. Krivonos (IKI, Moscow, Russian Federation), NASA/JPL-Caltech/R. Hurt (SSC-Caltech).
Background image: artist's concept sketch of the Galaxy taken from the Spitzer-GLIMPSE survey paper
http://iopscience.iop.org/article/10.1086/597811
