Columbia University Astronomy and 

MDM Observatory GRB Team

GRB 030329: Optical Decay
MDM 1.3m (4.3 x 4.3 arcmin display)

1.3m Mar. 30.20

RA = 10 44 49.957, Dec = +21 31 17.46 (J2000)

GCN Circular #2021: GRB 030329: Optical Decay
J. P. Halpern, N. Mirabal, M. Bureau (Columbia U.), K. Fathi (U. Nottingham)
report for the MDM Observatory GRB follow-up team:

We monitored the optical afterglow of GRB 030329 (=H2652, Vanderspek et al.
GCN 1997), identified by Peterson & Price (GCN 1985) and Torii (GCN 1986),
in the R-band with the MDM 1.3m for 7.5 hours beginning on March 30 03:05 UT, 
15.5 hours after the burst.  During this period, the magnitude declined from
R = 15.38 to R = 16.22, referenced to star "A" of Martini et al. (GCN 2012).
A fit to the 7.5 hour run yields a power-law decay slope of -1.934 +/- 0.005,
in agreement with contemporaneous measurements of Garnavich et al. (GCN 2018) 
and Smith (GCN 2019), although it is apparent that the slope is continuing to 
steepen further.

A graph of the preliminary differential magnitude light curve is available at

We thank J. Kemp for providing the data reduction pipeline.

This message may be cited.

The following figure will be updated if
more recent measurements become available.
Click here to receive the latest postscript version.
R-band light curve

Jules Halpern
Nestor Mirabal
Martin Bureau

Columbia University and MDM Observatory

MDM Observatory