The luminous `Seyfert 1' type II Supernova 1997ab

Astronomy & Astrophysics 324, L29 (1997)

H.-J. Hagen, D.Engels, D. Reimers

  1. Hamburger Sternwarte, Gojenbergsweg 112, D-21029 Hamburg, Germany


We report the discovery of SN 1997ab, a supernova with a Seyfert 1 type spectrum similar to SN 1987F. SN 1997ab was first seen at B=14.7+-0.5 on a digitized objective prism spectrum taken on April 11, 1996 for the Hamburg Quasar Survey with the Calar Alto 80cm Schmidt telescope and was automatically selected as a low redshift QSO candidate. Spectra and images taken with CAFOS at the 2.2m telescope on Calar Alto on Feb. 28 and March 2, 1997 show the SN at B=16.2 with strong Balmer lines, broad FeII emission bumps at lamda = 5250 Angstroem and 4580 Angstroem, a strong IR CaII triplet and the HeI 7065 Angstroem and 5876 Angstroem lines. The SN is located 3.7 arcsec southwest off the center of the faint (B~17.7) dwarf irregular HS 0948+2018. According to sharp HII region type [OIII], [NII], [SII] lines and sharp Balmer line components, the radial velocity of the parent galaxy is 3750 km/s. This yields a brightness on April 11, 1996 of MB=-19.1 (for Ho=65 km/ s/Mpc) and of MB=-17.6 on March 2, 1997. With its high luminosity and slow fading SN 1997ab is similar to SN 1988Z and SN 1987F. SN 1997ab can be expected to be observable for several years.

Key words: Supernovae: general -- Supernovae: individual: SN 1997ab

Contact: Hans-Juergen Hagen.

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