GCN Circular 3159
Subject
GRB050331: No Afterglow Detected
Event
Date
2005-03-31T20:47:13Z (21 years ago)
From
Aaron Price at AAVSO <aaronp@aavso.org>
B. Monard and A. Price report on behalf of the AAVSO International High Energy Network on
optical observations of the field of GRB050331 (GCN#3156 Palmer et al.).
A field centered on the coordinates of the XRT position in GCN #3155 (Burrows et al.) was
observed at midpoint time of 19:03 UT and compared with the DSS/POSS red plate. The CCD
was unfiltered but with a red zeropoint response.
No new source was identified down to a limiting magnitude (SNR=3) of 20.
Full details on the report is below along with a link to the FITS image:
Report filed on March 31 22:08 UT
Name: Berto Monard
email: bmonard@mweb.co.za
Site: Bronberg Observatory / CBA Pretoria
Location: -25 � 54' 48", 28� 26' 44"E
Elevation: 1590m
Scope: LX200 31cm
ScopeFocalRatio: f/3.7
CCDVendor: SBIG, ST-7XME
CCDPixelScale: about 1.8 arcsec /pixel
CCDFOV: 21 arcmin (E/W) x 14 arcmin (N/S)
Object: GRB 050331
ObsDate: 050331
ObsMidPointTime: 19 03 UT
Exposure per frame: 28 sec
NumberOfFrames: 35 stacked
Filters: none
Processing: dark/flat
Seeing: fair (about 3.5 arcsec)
LimitingMag: about 21CR for stack
Sky: open / no moon / object near zenith
afterglowmag: none down to magnitude 20CR
Report: the observed star field was set to be centered on 09 22 57 -41 25
48.
The obtained deep image was compared visually to a DSS-2 red image over the
entire error box of 4 arcmin.
No new object was found to an estimated limit of 20 CR and no further
observations are planned.
FITS image is located at http://www.aavso.org/tmp/grb050331.fits