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Direct identification of the progenitors of supernovae (SNe) is rare because of the required spatial resolution and depth of the archival data prior to the SN explosions. Here we report on the identification of the progenitors of two nearby SNe in the Virgo cluster: SN 2006my in NGC 4651 and SN 2006ov in M61. We obtained high-quality ground-based images of SN 2006my with the Canada-France-Hawaii Telescope, and are able to locate the site of the SN on pre-SN {it Hubble Space Telescope} ({it HST}) Wide Field Planetary Camera 2 images to a high precision (1$sigma$ uncertainty of $pm0farcs$05). We pinpoint the site of SN 2006ov to within 0$farcs$02 from {it HST} Advanced Camera for Surveys images of the SN. We detected a red supergiant progenitor for each SN within the error circles, with an inferred zero-age main-sequence mass ($M_{rm ZAMS}$) of $10^{+5}_{-3}$ $M_odot$ and $15^{+5}_{-3}$ $M_odot$ for the progenitors of SNe 2006my and 2006ov, respectively. The mass estimates for the progenitors of both SNe confirm a suggested trend that the most common Type II-plateau SNe originate from low-mass supergiants with $M_{rm ZAMS} approx 8$--20 $M_odot$.
The pre-explosion observations of the type II-P supernovae 2006my, 2006ov and 2004et, are re-analysed. In the cases of supernovae 2006my and 2006ov we argue that the published candidate progenitors are not coincident with their respective supernova s
We present the results of a 10.5 yr, volume limited (28 Mpc) search for supernova (SN) progenitor stars. We compile all SNe discovered within this volume (132, of which 27% are type Ia) and determine the relative rates of each sub-type from literatur
We review all the models proposed for the progenitor systems of Type Ia supernovae and discuss the strengths and weaknesses of each scenario when confronted with observations. We show that all scenarios encounter at least a few serious diffculties, i
Type IIb supernovae (SNe IIb) present a unique opportunity for investigating the evolutionary channels and mechanisms governing the evolution of stripped-envelope SN progenitors due to a variety of observational constraints available. Comparison of t
We have carried out a high-dispersion (R~30,000) echelle spectroscopic survey of 16 Type II supernovae (SNe) to search for narrow emission lines from circumstellar nebulae ejected by their massive progenitors. Circumstellar nebulae, if detected, prov