GRB 110519A
GCN Circular 12015
Subject
GRB 110519A: Swift detection of a burst
Date
2011-05-19T02:26:31Z (14 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
C. J. Saxton (UCL-MSSL), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), J. M. Gelbord (PSU),
S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (CRESST/GSFC/USRA),
C. B. Markwardt (NASA/GSFC), S. R. Oates (UCL-MSSL),
K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and
M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift Team:
At 02:12:16 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 110519A (trigger=453628). Swift did not slew because
of a Moon observing constraint.
The BAT on-board calculated location is
RA, Dec 261.629, -23.408 which is
RA(J2000) = 17h 26m 31s
Dec(J2000) = -23d 24' 29"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows a FRED pulse with a
duration of about 35 sec. The peak count rate was ~4000 counts/sec
(15-350 keV), at ~1 sec after the trigger.
Due to a Moon observing constraint, Swift cannot slew to the BAT
position until 23:19 UT on 2011 May 20. There will thus be no XRT or
UVOT data for this trigger before this time.
Although we note that this location is within 10 degrees of the
Galactic center, we believe that this is very likely a cosmological
GRB due to the strength of its emission above 100 keV.
Burst Advocate for this burst is C. J. Saxton (cjs2 AT mssl.ucl.ac.uk).
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
GCN Circular 12016
Subject
GRB 110519A, Swift-BAT refined analysis
Date
2011-05-19T13:02:09Z (14 years ago)
From
Hans Krimm at NASA-GSFC <hans.krimm@nasa.gov>
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), C. J. Saxton (UCL-MSSL),
J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 110519A (trigger #453628)
(Saxton, et al., GCN Circ. 12015). The BAT ground-calculated position is
RA, Dec = 261.638, -23.426 deg which is
RA(J2000) = 17h 26m 33.0s
Dec(J2000) = -23d 25' 32.2"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 50%. The mask-weighted light curve shows a FRED
profile starting at T-5 sec, peaking at T+3 seconds, and decaying gradually
with a featureless profile out to T+70 sec. A preplanned slew took the
source out of the BAT field of view at T+130 sec. T90 (15-350 keV) is
27.2 +- 3.0 sec (estimated error including systematics).
The time-averaged spectrum from T-4.7 to T+37.8 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
2.09 +- 0.06. The fluence in the 15-150 keV band is 4.0 +- 0.1 x 10-06
erg/cm2. The 1-sec peak photon flux measured from T+2.17 sec in the
15-150 keV band is 4.6 +- 0.3 ph/cm2/sec. All the quoted errors are at
the 90% confidence level.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/453628/BA/