Swift/XRT shows type I and type II bursting activity in the Rapid Burster
ATel #1969; G. Sala (UPC-IEEC), F. Haberl, W. Pietsch (MPE), J. JosÃ© (UPC-IEEC), A. Parikh (TUM)
on 14 Mar 2009; 17:53 UT
Credential Certification: Gloria Sala (email@example.com)
Subjects: X-ray, Binary, Neutron Star
The Rapid Burster (MXB1730-335) has been observed with Swift during its last outburst (ATel. #1939, ATel #1946), with a total of 20ks exposure time distributed between MJD 54888.7 (Feb. 26) and MJD 14895.8 (March 5). All observations show intense Type II (accretion driven) bursting activity, with bursts intervals between 25 and 200 seconds. Most bursts peak at more than 100 cts/s in the first Swift/XRT (WT) sequences (Feb. 26), which implies fluxes of about 10-8 erg/cm2/s. The peak intensity decreases in the last Swift observations, with most bursts showing maximum intensities of less than 60 cts/s in XRT (WT) on March 5.
A Type I (thermonuclear) burst is observed on March 5, rising to a maximum intensity of 10-8 erg/cm2/s in 3 seconds, with a thau~11s exponential decay, and showing indications of possible photospheric radius expansion.
We thank the Swift team for scheduling these observations.