New Outburst of The Rapid Burster (MXB 1730-335)
ATel #46; D. Fox, W. H. G. Lewin (MIT)
on 30 Sep 1999; 23:10 UT
Distributed as an Instant Email Notice Transients
Credential Certification: R. E. Rutledge (rutledge@srl.caltech.edu)
Subjects: X-ray, Binary, Transient
The Rapid Burster (MXB 1730-335) has been detected by the All-Sky
Monitor (2-12 keV) of the Rossi X-ray Timing Explorer satellite
(RXTE) in nine consecutive 90-second dwells beginning at 30
September 1999 04:46 UT. The source was detected at fitted count
rates between 8 and 16 cts/sec (per SSC), with uncertainties of ~2
cts/sec for each. During quiescence fitted count rates are generally
< 6 cts/sec and consistent with zero (3 sigma). Subsequent
observation with the RXTE Proportional Counter Array (PCA; 2-60
keV) on 30 September, beginning at 20:24 UT, found the source
exhibiting strong persistent emission with type I X-ray bursts, as
seen at the start of most recent outbursts (Guerriero et
al. 1999).
If the subsequent evolution of the outburst occurs as with these
previous outbursts then regular, rapid type II X-ray bursting will
commence on or about 10 October, and last for roughly 12 days. High
time resolution (<10 sec) infrared observations of the source
during this time may reveal IR counterparts to the type II X-ray
bursts, since these are expected to reach K~16.5. Please contact the
authors to arrange possible coordination with RXTE
observations. (See also the Rapid Burster Page.)
The coordinates of the Rapid Burster's (likely) VLA counterpart (IAUC
# 6813 ; ATEL #8) are RA=17h33m24s.61; Dec=-33d23m19s.8 (J2000).
