GCN Circular 3340
Subject
GRB050502A: Optical Observations
Event
Date
2005-05-03T02:42:36Z (21 years ago)
From
Aaron Price at AAVSO <aaronp@aavso.org>
D.T. Durig (Cordell-Lorenz Observatory - The University of The South) reports on
behalf of the AAVSO International High Energy Network on optical observations of
GRB050502A (GCN #3323, Gotz et al.):
Durig reports the following rapidly fading behavior:
Date (UT) Mag
02.17880 19.8
02.18243 20.8
02.18606 20.3
02.18969 20.4
02.19331 20.5
02.19694 20.9
02.20056 21.4
02.20418 21.4
02.20781 21.0
02.21144 21.3
Observations were made unfiltered based on a V zeropoint. Uncertainly is +/- 0.4
magnitudes. Details of the observation are below along with a link to the co-added
FITS image.
Full Observation Details
Name: Dr. Douglas T. Durig
email: ddurig@sewanee.edu
Observer: D. T. Durig ( CLW01)
Site: Cordell-Lorenz Observatory
Location: Sewanee, TN, USA
LatitudeLongitude: 35 12 N 85 55 W
Elevation: 600 m
Scope: SCT 0.30 m
ScopeFocalRatio: f/5.8 1766 mm FL
CCDVendor: SBIG ST1001E
CCDDetector: KAF1001E
CCDSize: 1024x1024
CCDPixelScale: 2.8 arc sec/ pixel
CCDFOV: 48x48 full, 12x12 cropped submitted
Object: GRB050502
ObsDate: 2005 05 02
ObsMidPointTime: 2.15912 (04 40 58 UT )
TimePerFrame: 300 sec
NumberOfFrames: 11
Filters: CV
Processing: dark, flat, registered, added, quarter frame cropped
Seeing: 4 to 5 arc sec
LimitingMag (SNR=3): 21.0 ???
Sky: very clear
afterglowmag: 20 fading to 21 during first hour
afterglowerr: 0.4
compstars: 900 USNO B1.0 stars
Report: I could see the afterglow candidate in my first few images but it was
fading fast and I had to stack to see it well in later images.
Ave Position:13 29 46.28 +42 40 27.7
I get the following magnitudes for co-added (10min) frames:
02.17880 19.8 CV
02.18243 20.8 CV
02.18606 20.3 CV
02.18969 20.4 CV
02.19331 20.5 CV
02.19694 20.9 CV
02.20056 21.4 CV
02.20418 21.4 CV
02.20781 21.0 CV
02.21144 21.3 CV
A FITS image has been uploaded to
ftp://ftp.aavso.org/grb/Dr.DouglasT.Durig_GRB050502_2453492.77287_.fits
The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network.