GCN Circular 28914
Subject
Swift Trigger 1006917 is Be/X-ray binary pulsar 1A 0535+262
Date
2020-11-17T00:33:31Z (3 years ago)
From
Kim Page at U.of Leicester <klp5@leicester.ac.uk>
N. J. Klingler (PSU), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester) and
A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:
At 00:12:35 UT, the Swift Burst Alert Telescope (BAT) triggered and
located 1A 0535+262 (trigger=1006917). Swift slewed immediately to the pulsar.
The BAT light curve showed a multi-peaked structure with a duration
of about 25 sec. The peak count rate was ~4000 counts/sec (15-350 keV),
at ~0 sec after the trigger.
The XRT began observing the field at 00:13:11.5 UT, 35.8 seconds after
the BAT trigger, and detected 1A 0535+262.
The initial flux in the 0.1 s image was 2.93e-08 erg cm^-2 s^-1 (0.2-10
keV).
BAT also triggered on this source several times earlier tonight,
between 23:00 and 23:13 UT on November 16 (trigger numbers 1006906,
1006907 and 1006911). All of these triggers occurred during star
tracker loss of lock. Because of the star tracker problems, the
coordinates provided in the automatic GCN Notices are unreliable.