[AAVSO-HEN] GRB Field Observation Report

[grb at aavso.org]

 Report filed on Thu Oct  7 06:15:53 2004:

 Name: Dr. D. T. Durig
 email: ddurig at sewanee.edu
 Observer: D. T.  Durig, C. E. Donald, M. L. Greenwood, ( CLW01)
 Site: Cordell-Lorenz Observatory
 Location: Sewanee, TN, USA
 LatitudeLongitude: 35 55 N, 85 55 W
 Elevation: 600 M
 Scope: 0.30-m SCT
 ScopeFocalRatio: f/5.8 1768 mm FL
 CCDVendor: SBIG STL-1001E
 CCDDetector: KAF1001E
 CCDSize: 1024x1024
 CCDPixelScale: 2.8 arc sec/pixel
 CCDFOV: 47.5x47.5
 Object: GRB041006
 ObsDate: 2004 10 07
 ObsMidPointTime: 05 25 31 UT
 TimePerFrame: 300 sec
 NumberOfFrames: 8
 Filters: CV
 Processing: dark,flat,register,add,crop, removed hot/cold pixels
 Seeing: 5 arcsec
 LimitingMag: 20.0
 Sky: fog, wind, dew
 afterglowmag: 19.9 mag
 afterglowerr: 0.5 mag
 compstars: 278 USNO B1.0  nearby stars
 Report: 48 arc min field centered near optical afterglow candidate. Position measured was 

00 54 51.59, +01 14 10.4   ~19.9 mag

error due to poor seeing and windy conditions as well as near limiting magnitude of source.
 comments: Fog and dew entered the picture after the first 2 of 24 five minute long images and only the first 8 were co-added to produce the final image. It shows a very dim source at almost exactly the correct location at about 19.9 mag, just under our 3 sigma limit of 20 mag.

I also mis-typed first target location and found new asteroids nearby during my first two hours spent imaging a degree away from GRB afterglow candidate.

A FITS image has been uploaded to ftp://ftp.aavso.org/grb/Dr.D.T.Durig_GRB041006_2453285.92770_.fits