(fwd) GRB 20030329, more observation data, astrometry (Monard) Tabulated report Contact name: Berto Monard Contact e-mail: bmonard@mweb.co.za Observer: Berto Monard / MLF Site Name: Bronberg Observatory Nearest town: Pretoria / South Africa Site latitude: 25deg 55min South Site longitude: 28deg 27min East Site elevation: 1590m Telescope type: SCT / 30cm Telescope focal ratio: f/4.2 effectively CCD camera: SBIG ST-7E CCD detector: KAF-0401E CCD dimensions: 765x510 pixels CCD pixel scale: 1.52 arcsec/pixel F.O.V: 18 arcmin E-W x 12.5 arcmin N-S GRB object name: GRB 030329 Observation date: 20030329 UT Observation start time: 17 15 UT Observation end time: 23 37 UT Exposure time per frame: 45 sec Number of stacked frames: results of timeseries photometry on optical = transient, no stacking Filters used: unfiltered / CR Processed: FF, DS, AIP4WIN reduction Estimated seeing: 4 arcsec FWHM Limiting magnitude: 17.0CR to 18.0CR per frame UCAC1 differentials Sky conditions: clear, cloud passages halfway measurements, average = seeing Details of observation: The reported bright optical transient of GRB 20030329 was monitored over a duration of just under 6.5 hours continuously with 60 sec imaging cycles. Using differential photometry based on one Tycho II star just South of the field, the optical transient faded from 13.8CR to 14.7CR over the reported period. It is possible that these magnitudes are about 0.3 to 0.4 magnitude too bright. It is not impossible that QPOs (at 0.3h and/or 0.95h) are present. These periods seem to shorten towards the end of the run... A polynomial fit of the second degree (quite good at 0.99963) through the lightcurve produced the following fading rates: 0.19CR/hour around JD ..2728.22 0.11CR/hour around JD ..2728.48 At these rates the OT will be around for quite sometime still. Other measurements: Astrometry on a stack of the best images gave the following (2000) position for the transient, traceable to USNO-A2.0: 10 44 50.05 +21 30 10.5 A .fts image will be sent to A Price at aaronp@aavso.org . The photometric run data and the image can be made available. This report can be cited.
Return to the Powerful Daisaku Nogami
vsnet-adm@kusastro.kyoto-u.ac.jp