Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 22780

Subject
GRB 180614A: Swift detection of a burst
Date
2018-06-14T19:28:07Z (6 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
J.D. Gropp (PSU), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
J. A. Kennea (PSU), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), M. H. Siegel (PSU),
A. Tohuvavohu (PSU) and T. N. Ukwatta (LANL) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 19:16:13 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 180614A (trigger=841548).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 3.157, +46.943, which is 
   RA(J2000)  =  00h 12m 38s
   Dec(J2000) = +46d 56' 34"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a couple peaks
with a duration of about 25 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~2 sec after the trigger. 

The XRT began observing the field at 19:17:19.1 UT, 65.6 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 3.07620, 46.95342 which is equivalent
to:
   RA(J2000)  = 00h 12m 18.29s
   Dec(J2000) = +46d 57' 12.3"
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This
location is 202 arcseconds from the BAT onboard position. This position
may be improved as more data are received; the latest position is
available at http://www.swift.ac.uk/sper.  We cannot determine whether
the source is fading at the present time. This position is more than
2-sigma away from the BAT position, and so possibly unrelated to the
trigger. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 1.14
x 10^21 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 68 seconds after the BAT trigger. No credible
afterglow candidate has  been found in the initial data products. The
2.7'x2.7' image covers none of the XRT  error circle. Data from the list of
sources generated  on-board are not available at this time. 

Burst Advocate for this burst is J.D. Gropp (jdg44 AT psu.edu). 
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.)
Looking for U.S. government information and services? Visit USA.gov