Probing the Distance to X-Ray Flashes
with XRF 020903
XRF 020903
was a bright X-ray flash (XRF) detected by the HETE-2 satellite on September
3 2002. An optical afterglow component was discovered one week
later on September 10 by comparing two sets of images taken with the Caltech
Palomar Observatory 200 inch telescope. This afterglow was the first detected
optical component of an X-ray flash, linking this class of high energy
events with the more energetic set of gamma-ray bursts (GRBs). We obtained
a spectrum of the afterglow component on September 28 2002 showing the object
to be cosmological in origin and at a distance of 4 billion lightyears from
Earth. This observation of XRF 020903 has thus set the distance scale for
the class of X-ray flashes.
- Read about this exciting new discovery
in the National News
(Sky and Telescope, Astronomy
Magazine, Science....etc.)
The Optical Discovery: The image stamps shown above
were taken with the 200 inch Palomar telescope on September 4th and 10th.
Through image subtraction techniques we were able to uncover the afterglow
component associated with XRF 020903, the first of such components to
be discovered in association with an X-ray flash.
The field of XRF 020903: The image above was taken with the 200 inch Palomar telescope
on September 4 2002 (1 day after the event). The cutout region marks
a portion of the field observed with the Hubble Space Telescope (HST) on
December 3 2002. The location of the optical afterglow is marked with a
circled and labeled OT (optical transient).
High Resolution Images (tiff format):
- HST host galaxy complex (10
x 10 arcseconds, unannotated, color): Link
- HST host galaxy complex (10
x 10 arcseconds, unannotated, B+W): Link
For more information please contact:
Alicia
Soderberg
Caltech Astronomy Department
MC 105-24
1201 E. California Blvd.
Pasadena, CA 91125
ams@astro.caltech.edu
(626) 395-6645
Additional Links:
page by A. M. Soderberg
Send comments to: ams@astro.caltech.edu
