SDSS J124602.54+011318.8: A Highly Luminous Optical Transient at z=0.385

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Updated version to appear in ApJ

Scientific paper

10.1086/341887

We report the discovery of a highly luminous optical transient (OT), SDSS J124602.54+011318.8, associated with a galaxy at a redshift of 0.385. In this paper we consider the possibility that the OT may be a GRB afterglow. Three sets of images and two sets of spectra were obtained as part of the normal operations of the Sloan Digital Sky Survey (SDSS). In the first two image sets, observed two nights apart, the object appears as a point source at $r^{*}\approx 17$. The third image set, observed about 410 days later, shows an extended source which is more than 2.5 magnitudes fainter. The spectra were observed about 400 and 670 days after the first two image sets, and both show an apparently normal galaxy at a redshift of 0.385. Associating the OT with the galaxy, the absolute magnitude was $M_{r^*}=-24.8$, which is over 4 magnitudes brighter than the most luminous supernova ever measured. The spectral energy distributions of the galaxy-subtracted OT derived from the first two image sets are well-fit by single power-laws with indices of $\beta_{\nu}=-0.92$ and -1.29 respectively, similar to most GRB afterglows. Based upon the luminosity of the OT, non-detections in contemporaneous ROTSE-I images, and the change in spectral slope, the OT, if an afterglow, was likely discovered early during a ``plateau'' or slowly-fading phase. The discovery of a GRB afterglow at this stage of the SDSS is consistent with expectations, but only if the optical emission is much less strongly beamed than the gamma-rays. We emphasize that other explanations for the OT cannot be ruled out; a recent follow-up study by [galyam02] provides strong evidence that this source is in fact an unusual AGN.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

SDSS J124602.54+011318.8: A Highly Luminous Optical Transient at z=0.385 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with SDSS J124602.54+011318.8: A Highly Luminous Optical Transient at z=0.385, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and SDSS J124602.54+011318.8: A Highly Luminous Optical Transient at z=0.385 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-481265

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.