TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2078
SUBJECT: GRB030329: multiple re-brightening phases
DATE:    03/04/03 08:56:27 GMT
FROM:    Weidong Li at UC Berkeley KAIT/LOSS  <weidong@astron.berkeley.edu>

Weidong Li, Ryan Chornock, Saurabh Jha, and Alexei V. Filippenko (UC Berkeley)
report:

We collected the available R-band measurements of the GRB 030329
afterglow through GCN 2077 and a table is available at
http://astron.berkeley.edu/~bait/grb/gcn030329.r.dat

We found that the afterglow went through at least three re-brightening
phases. A figure illustrating this can be found at
http://astron.berkeley.edu/~bait/grb/grb030329.p3.ps

The first re-brightening, as reported by Lipkin et al. (GCN 2045) and
Burenin et al (GCN 2046),  occurred at about 30 hours after the burst.
The second re-brightening, as reported by Lipkin et al. (GCN 2060), 
occurred at about 60 hours after the burst. A third re-brightening
occurred at about 80 hours after the burst. 

The afterglow appears to decline with a power law after each re-brightening.
The following power-law indices are measured for the three dashed lines
in our plot:

t = 16 to 30 hours:  alpha = -1.70 +/- 0.04
t = 40 to 60 hours:  alpha = -1.63 +/- 0.07
t = 64 to 70 hours:  alpha = -2.09 +/- 0.26

A preliminary analysis of the data reported in GCN Circulars
suggests that the afterglow shows the same behavior in the
other bands (BVI) as well, though the re-brightening episodes 
were less constrained than in the R band.

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