Infrared Detection and Spectroscopy of Embedded Supernovae in Actively Star Forming Galaxies

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

AWARD NO: AST-0607737 PI: Michael Skrutskie INSTITUTION: University of Virginia Main Campus TITLE: Infrared Detection and Spectroscopy of Embedded Supernovae in Actively Star Forming Galaxies ABSTRACT Massive stars are the likely energy sources powering starburst and interacting galaxies which therefore should be hosts to frequent supernova events. Yet, contrary to expectations, surveys for supernovae among such galaxies have established rates which are comparable to supernovae rates observed in more normal and/or isolated galaxies. However, the bulk of these surveys are also conducted at visible wavelengths where obscuration by dust associated with star formation and competition from nuclear flux may result in observers "missing" supernovae. Here a supernova search program will be implemented in the near infrared (Ks-band, 2.17 m) where the extinction by dust will be significantly reduced and the supernovae themselves will be brighter. The survey will be carried out at the University of Virginia's Fan Mountain Observatory using the 31-inch telescope and HAWAII-1 infrared camera (developed through an NSF Major Research Instrumentation grant). Fifty program galaxies, 30 with infrared luminosities in excess of 2 x 1010LSun and within 32 Mpc, and 20 of the nearest galaxies more luminous than 1 x 1010LSun, will be targeted and observed monthly for supernovae. Detected supernovae will be fed to the PAIRITEL automated 1.3-meter telescope at Mt. Hopkins, AZ for simultaneous J-, H-, and Ks-band imaging to determine light curves. Brighter supernovae will also trigger target-of-opportunity spectroscopic observations with the TripleSpec near-infrared spectrograph at the Apache Point Observatory 3.5-meter telescope. The infrared spectra and light curves will allow the classification of the supernovae as a function of environment, which will in turn allow the progenitor populations to be characterized. The overall goals are a better estimate of the local supernovae rate and more extensive observations of spectroscopic signatures diagnostic of envelope structure and interaction with the surrounding medium. This work will support the training of a graduate student who will be responsible for the post-commissioning science program with TripleSpec using data from the imaging survey which the student will also lead. This student will be deeply integrated into the final assembly and testing of TripleSpec and its commissioning at the telescope. Undergraduates from the University of Virginia will take part in the acquisition of data at the Fan Mountain Observatory with hope of cultivating new instrumentalists in addition to astronomical observers.