The Discovery and Nature of Optical Transient CSS100217:102913+404220
Abstract
We report on the discovery and observations of the extremely luminous optical transient CSS100217:102913+404220 (CSS100217 hereafter). Spectroscopic observations show this transient was coincident with a galaxy at redshift z=0.147, and reached an apparent magnitude of V ~ 16.3. After correcting for foreground Galactic extinction we determine the absolute magnitude to be M_V =-22.7 approximately 45 days after maximum light. Based on our unfiltered optical photometry the peak optical emission was L = 1.3 x 10^45 erg s^-1, and over a period of 287 rest-frame days had an integrated bolometric luminosity of 1.2 x 10^52 erg. Analysis of the pre-outburst SDSS spectrum of the source shows features consistent with a Narrow-line Seyfert1 (NLS1) galaxy. High-resolution HST and Keck followup observations show the event occurred within 150pc of nucleus of the galaxy, suggesting a possible link to the active nuclear region. However, the rapid outburst along with photometric and spectroscopic evolution are much more consistent with a luminous supernova. Line diagnostics suggest that the host galaxy is undergoing significant star formation. We use extensive follow-up of the event along with archival CSS and SDSS data to investigate the three most likely sources of such an event; 1) an extremely luminous supernova; 2) the tidal disruption of a star by the massive nuclear black hole; 3) variability of the central AGN. We find that CSS100217 was likely an extremely luminous type IIn supernova that occurred within range of the narrow-line region of an AGN. We discuss how similar events may have been missed in past supernova surveys because of confusion with AGN activity.
Cite
@article{arxiv.1103.5514,
title = {The Discovery and Nature of Optical Transient CSS100217:102913+404220},
author = {A. J. Drake and S. G. Djorgovski and A. Mahabal and J. Anderson and R. Roy and V. Mohan and S. Ravindranath and D. Frail and S. Gezari and James D. Neill and L. C. Ho and J. L. Prieto and D. Thompson and J. Thorstensen and M. Wagner and R. Kowalski and J. Chiang and J. E. Grove and F. K. Schinzel and D. L. Wood and L. Carrasco and E. Recillas and L. Kewley and K. N. Archana and Aritra Basu and Yogesh Wadadekar and Brijesh Kumar and A. D. Myers and E. S. Phinney and R. Williams and M. J. Graham and M. Catelan and E. Beshore and S. Larson and E. Christensen},
journal= {arXiv preprint arXiv:1103.5514},
year = {2015}
}
Comments
submitted to ApJ