Was Fritz Zwicky's "Type V" SN 1961V a Genuine Supernova?
Abstract
In 1989, Goodrich and collaborators suggested that SN 1961V, a very peculiar Type II (Zwicky's "Type V") supernova, was not the final explosion of a star at the end of its life, but rather the giant eruption of a massive, luminous blue variable, like n Car. To test this hypothesis, we have used the Hubble Space Telescope to obtain optical images of the site of SN 1961V. There is a cluster of faint (V ~ 24-25 mag), blue [(V-I)_0_ = -0.4-0.5 mag] stars around the general location of the supernova. We also see a very faint (V = 25.6 +/- 0.3 mag), much redder [(V-I)_0_ = 1.7 mag] star barely resolved from one of the blue stars. Its brightness and colors are consistent with those of a highly reddened O-type star, as predicted by Goodrich et al. Moreover, it is the star formally closest to the known radio position of SN 1961V; the coordinates are identical, to within the uncertainties. Thus, we tentatively identify this as the post eruption star of SN 1961V; it survived the giant eruption, which was not a genuine supernova, and it is now red due to a substantial envelope of dust (A_V_ ~ 4.1 mag). However, the current data do not allow us to eliminate the possibility that this star is an unrelated red supergiant or a peculiar supernova remnant. Alternatively, the blue object adjacent to it may be the actual post- eruption star of SN 1961V. If so, the envelope of dust is not as thick: A_V_ ~ 2.2-3.2 mag, but perhaps somewhat larger if the object's colors are significantly affected by a blue light echo of SN 1961V.
- Publication:
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The Astronomical Journal
- Pub Date:
- November 1995
- DOI:
- 10.1086/117687
- Bibcode:
- 1995AJ....110.2261F
- Keywords:
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- SUPERNOVAE: INDIVIDUAL: SN 1961V;
- CATACLYSMIC VARIABLES