GRB030329 Afterglow Imaged at Tokyo Tech！
The afterglow of the gamma-ray burst GRB030329 was imaged successfully using
a small telescope (30cm aperture) placed on the roof of the Main
Campus Building of Tokyo Institute of Technology, Ookayama, Meguro-ku,
Tokyo. It is really amazing that a source at a cosmological
distance was imaged in the bright city sky of Tokyo with an
amateur-class small telescope.
Images of GRB030329 imaged at Tokyo Tech
These four images were taken at 12:57, 15:00, 17:08, and 18:32 UTC on
29 Mar 2003 (80 min, 3 hr 23 min, 5 hr 30 min, and 6 hr 55 min after the
burst onset respectively). The bright source at the center of the
images are seen to become fainter as compared to the surrounding stars.
(Images by Rie
Sato, using Meade LX-200 12" with Apogee AP-6E CCD camera)
Light curve of the optical afterglow
We have observed the afterglow of GRB030229 on the nights of 2003 Mar
29, 30, and 31.
We have estimated the R magnitude using USNO 2.0 stars U1050_06349885
(R=13.2), B:U1050_06348771 (R=14.2), and C:U1050_06351075 (R=14.0).
Please see the image below for the stars used for reference.
The resultant light curve is shown below. A dip and
rebrightening at t0+1.2d can be seen..
GRB030329 OT (yellow circle) and USNO stars USNO 2.0 stars (green
circles) A:U1050_06349885 (R=13.2), B:U1050_06348771 (R=14.2), and
C:U1050_06351075 (R=14.0).
GRB030329
The Gamma-ray burst GRB030329 was detected by HETE-2 on 11:37:14 UTC on
29 March 2003, and its location based on the
ground analysis was disseminated to the community 73 minutes through Gamma-Ray Burst Coordinate Network
(GCN). Based on the HETE localization, Peterson and Price
in Australia and Torii
in Japan discovered an optical afterglow and reported to GCN
immediately. We also started the observation at the HETE alert,
and we detected the afterglow independently. The localization and
the gamma-ray light curve of GRB030329 is shown at the burst page at
MIT. A later spectroscopic observation using Very Large Telescope
at European Southern Observatory revealed that the source has a redshift
of 0.1685, the smallest of the confirmed GRB afterglow ever recorded
(except for GRB980426/SN1998bw) (GCN Circ. 2020).
HETE-2 (High Energy Transient Explorer 2) is a satellite designed to
localize the gamma-ray bursts and notify their locations immediately to
the observers around the world, so that the follow up observations of
the source can be made quickly from the ground-based tesescopes and
other satellites. It is a small and inexpensive satellite, but it
is built with numerous innovative and advanced features. It is a
international collaboration of US, Japan, and France. For details
see the HETE page at MIT. The
gamma-ray burst group at Tokyo Tech is lead by Nobu Kawai, a member of
HETE team of Japan who built the Wide Field X-ray Monitor (WXM) at
RIKEN. The graduate students are engaged in the operations and
analysis of the data from HETE-2, and optical followup of gamma-ray
burst afterglows.
Related links
HETE page at RIKEN
HETE page at MIT
GCN home pate at NASA
GRB030329 page at Bisei Astronomical Observatory
GRB030329 page of VSNET (variable star network)
J
band images of GRB030329 at Gunma Astronomical Observatory
Greiner's GRB030329 page