burst in 1E 1145.1-6141
ATel #290; A. Bodaghee (ISDC), N. Mowlavi (ISDC), J. Ballet (CEN-Saclay)
on 12 Jun 2004; 17:47 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Nami Mowlavi (Nami.Mowlavi@obs.unige.ch)
Subjects: X-ray, Gamma Ray, Transient, Pulsar
Referred to by ATel #: 1440
We report the brightening of the high-mass X-ray binary 1E 1145.1-6141 by a
factor of 4 in 20--60 keV between June 10 (00:00 UTC) and June 11 (09:30 UTC),
reaching about 130 mCrab in this energy range. The burst was recorded by the
ISGRI detector on board INTEGRAL during an open observation of the Carina region.
To our knowledge, no such burst has been mentioned in the literature so far,
as the source is believed to be a persistent and steady X-ray pulsar with a
flux up to 20--30 mCrabs (Grebenev et al., 1992, see also Ray & Chakrabarty, 2002).
No increase is detected by ISGRI in 60--200 keV. In the only pointing for
which 1E 1145.1-6141 was in the JEM-X FOV (June 11, 03:30 UTC), the flux is
about 40 mCrab in 3--10 keV.
Further observations during the Carina open program on June 12th shows a decrease
of the flux below 100 mCrab. This would indicate that 1E 1145.1-6141 went into
an episode of burst of about 2 days.