The emission line galaxy TV Reticuli

Evidence for an ultraluminous supernova

¹ European Southern Observatory, Casilla 19001, Santiago 19, Chile e-mail: lschmidt@eso.org
² Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica, Casilla 306, Santiago 22, Chile
³ Zentrum für Astronomie, ITA, Universität Heidelberg, Albert-Überle-Str. 2, 69120 Heidelberg, Germany

Received: 26 July 2006
Accepted: 10 October 2006

Abstract

Aims.TV Ret was classified as a cataclysmic variable due to an outburst observed in 1977. We intended to confirm this classification and derive some basic properties of the system.

Methods.Low resolution optical spectra were obtained for a spectral classification of the object.

Results.We find that the object is not a cataclysmic variable but an emission line galaxy with a redshift . An R-image taken in very good seeing conditions shows that the object is extended.

Conclusions.We show that TV Ret is a blue dwarf galaxy, probably compact, with an absolute magnitude of M_B = -17.5, a metallicity of 0.12 solar, and an average temperature of  K. The line ratios place it among the H II galaxies, although close to the border of the Seyfert 2s. The outburst, which was observed in 1977, could thus be explained by a supernova explosion. However, with an absolute magnitude around M_B = -21, it was an extremely bright one.