GRB 050817
GCN Circular 3819
Subject
GRB050817: Swift-BAT Detection of a burst
Date
2005-08-17T12:56:27Z (20 years ago)
From
Derek Fox at CIT <derekfox@astro.caltech.edu>
D.B. Fox (PSU), S. Barthelmy (GSFC), H. Krimm (GSFC/USRA), D. Burrows
(PSU), A. Blustin (UCL-MSSL), N. Gehrels (GSFC), J. Osborne
(U. Leicester), J. Kennea (PSU), T. Sakamoto (GSFC/NRC), P. Roming
(PSU) report on behalf of the Swift team:
At 12:19:58 UT, Swift-BAT triggered and located GRB050817
(trigger=150823). The BAT on-board calculated location is RA,Dec
285.028 d, -24.930 d {19h 00m 07s, -24d 55' 48"}, with an uncertainty
of 2 arcmin (radius, 90%-containment, stat+sys). The BAT light curve
shows a single peak of about 4 seconds duration. The peak count rate
was ~600 counts/sec (15-350 keV) at ~2 seconds after the trigger.
Swift was unable to slew to the source due to the moon constraint.
X-ray telescope and UV/optical telescope observations of this region
will become possible at about 06:00 UT on 18 August 2005.
We note that the BAT position is 43 arcsec from the position of the
2.65-ms accreting X-ray pulsar HETE J1900.1-2455 (Vanderspek et
al., ATEL #516; Fox, ATEL #526). Thus we cannot rule out that this
BAT trigger is due to HETE J1900.1-2455.
GCN Circular 3820
Subject
GRB050817: Negative Optical Observations
Date
2005-08-17T15:35:14Z (20 years ago)
From
Aaron Price at AAVSO <aaronp@aavso.org>
P. Nelson (Ellinbank Observatory - Ellinbank, Australia) and A. Price (AAVSO) report on
behalf of the AAVSO International High Energy Network on optical observations of GRB050817
(GCN #3819; Fox et al.).
No counterpart is detected to less than Rc=16. The observation covered the entire error
pattern and the exposure midpoint was 14:18 UT. Full details and URL to the FITS image are
below.
The AAVSO thanks the Curry Foundation for support of the AAVSO International High Energy
Network.
Report filed on Wed Aug 17 11:22:17 2005:
Name: Peter Nelson
email: pnelson@dcsi.net.au
Observer: Peter Nelson
Site: Ellinbank Observatory
Location: Ellinbank
LatitudeLongitude: -38 14 47.4 / 145d 57' 30.4"E
Elevation: 138m
Scope: 0.32m Newtonian
ScopeFocalRatio: f/5
CCDVendor: SBIG, ST8XE
CCDDetector: KAF 1602E
CCDSize: 498 x 468
CCDPixelScale: 1.16 arc"
CCDFOV: 9.6 x 9
Object: 050817
ObsDate: 050817
ObsMidPointTime: 14:18
TimePerFrame: 100
NumberOfFrames: 1
Filters: R
Processing: dark, flat
Seeing: 5 arc"
LimitingMag: 16
Sky: Moon, cloud
afterglowmag:
afterglowerr:
compstars:
Report: Error box covered.
comments: Gap in cloud. Did not get time to focus properly. Moon light interferred with
observation. Only one exposure possible before cloud came over. A FITS image has been
uploaded to ftp://ftp.aavso.org/grb/PeterNelson_050817_2453600.14047_.fits
GCN Circular 3823
Subject
GRB 050817: Optical observations
Date
2005-08-17T19:20:46Z (20 years ago)
From
Javier Gorosabel at LAEFF-INTA, Madrid <jgu@laeff.esa.es>
P. Tristram (Canterbury Univ. Mt John Observatory),
A. de Ugarte Postigo, J. Gorosabel, S. Guzyi, M. Jel��nek,
A.J. Castro-Tirado(IAA-CSIC), Ph. Yock (Univ. of Auckland) report
" We have observed the field of GRB050817 (Fox et al., GCN 3819) with
the 0.6m MOA telescope at Mt. John Astronomical Observatory using the
wide red and wide blue MOA filters. A combination of 3x300s red-band
exposures with mean epoch at 14:18:00 UT (1.97 hours after the burst)
shows no new object in the error-box down to a limiting magnitude of
18.5. We note that there is a saturated difraction spike from a nearby
star crossing the field which hides aproximately 5% of it."
This message can be cited.