Western Kentucky University, Physics and Astronomy, Bowling Green, KY 42101
Originally completed in 2001, the Nearby Galaxies Supernova Search (NGSS) Project surveyed approximately 900 square degrees along the celestial equator to find low redshift supernovae. This survey intended to measure the rate of supernovae occurrences in nearby galaxies, and map out the diversity of supernova characteristics. I will present our recent re-analysis of the NGSS data, using careful, pixel-by-pixel examinations of new time intervals between templates and search images to locate supernovae that may have been missed in the original survey. We also use a more comprehensive method, making use of multi-wavelength archival data from Great Observatories (Hubble, Chandra, etc.), to distinguish active (optically variable) galaxy nuclei (AGN) from possible supernovae within the cores of these galaxies. To date, in addition to the 42 supernovae originally discovered, we have uncovered at least one strong supernova candidate that was missed in the original survey, and approximately 15 less definitive candidates, including possible AGN. When complete, our results should improve the precision of the event rates for supernovae of all types in galaxies in the local (z < 0.1) universe.
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