Possible new source IGR J17391-3021 or an outburst from XTE J1739-302
ATel #181; R. Sunyaev (IKI, Moscow/MPA, Garching), A. Lutovinov (IKI, Moscow), S. Molkov (IKI, Moscow), S. Deluit (ISDC)
on 27 Aug 2003; 14:14 UT
Distributed as an Instant Email Notice Request For Observations
Credential Certification: A.Lutovinov (aal@hea.iki.rssi.ru)
Subjects: X-ray, Gamma Ray, Request for Observations, Binary, Transient
We report a detection of a possible new transient source IGR J17391-3021
with the IBIS/ISGRI detector onboard the INTEGRAL
observatory. The source position is RA = 17h39.1m, Dec = -30o21.5'
(equinox 2000, uncertainty 3'). It is close to the position of the known
transient source XTE J1739-302 (angular distance is ~5.5') and taking
into
account that uncertainty of the position of XTE J1739-302 is 4.8'
(Smith et al. 1998, ApJ, 501, L181) we cannot exclude that INTEGRAL
detected an outburst from XTE J1739-302.
The begin of outburst was detected on Aug 26, 2003 UT18:49 at the level
of ~70 mCrab in the 18-50 keV energy band. The source flux was found to
be
highly variable (in factor of ~10) on the timescale of thousands of
seconds. Maximum flux was detected around Aug 27, 2003 UT00:44 at ~150
mCrab
in the 18-50 keV band. In that moment the source was also detected in a
hard energy band 50-100 keV with a flux ~50 mCrab.
We encourage follow up observations at various wavelengths.
