GALEX ToO UV Spectroscopy of Nearby Core-Collapse SNe

Latest results (1): GALEX spectroscopy of SN 2005ay in NGC 3938

Comparison with HST spectra of SN 1999em and Swift/UVOT spectra of SN 2005cs shows a remarkable similarity; the combined imformation from these three events now allow to trace the UV spectral evolution of SNe II-P during the first month after explosion; from Gal-Yam et al. 2008.

Latest results (2): GALEX observations of our latest ToO target, SN 2008aw:

This interesting object (transition between type II-P and II-L) was well detected by GALEX. This observational campaign is still underway.

Supernova (SN) explosions play a pivotal role in triggering, driving, and (later on) inhibiting further star formation in galaxies. In fact, the combination of new observations and refined modelling shows that the little-understood and poorly constrained contribution of SNe to galaxy evolution processes (often hidden under the generic name of ``feedback'') is probably the weakest link in our understanding of structure formation in the Universe. Setting observational limits on the rate, environments, and energy output of high-redshift SNe is therefore one of the main science drivers of recent Hubble Space Telescope (HST) legacy programs, as well as of future missions like the James Webb Space Telescope (JWST). However, observations of high-redshift SNe in the optical (by HST), or in the near-IR (by JWST), actually sample the rest-frame UV of these objects. Thus, proper interpretation of these observations requires knowledge about the UV properties of SNe. Unfortunately, UV spectroscopy of local SNe of all types, which can only be obtained from space, is almost non-existent. Such UV data are also powerful probes of the SN environment, progenitor structure and explosion physics.

We have been pursuing a GALEX program (cycles 1-4; PI Gal-Yam) to obtain target-of-opportunity GALEX spectroscopic observations of nearby, bright non-Ia (core-collapse) SNe. Accumulated data (4 events observed so far, see below lead towards a full characterization of the UV spectral evolution of SNe of all types.


  • GALEX Spectroscopy of SN 2005ay suggests a UV spectral uniformity among type II-P supernovae


  • Type II-Plateau Supernova 2005ay: an extensive study from Ultraviolet to Near-Infrared (Cefalu 2006)
  • The Type IIP SN 2005ay: An Extensive Study From UltraViolet To Near-IR (Prague 2006)


  • SN 2005ay (cycle 1)
  • SN 2007aa (cycle 3)
  • SN 2007gr (cycle 3)
  • SN 2008aw (cycle 4)


  • Avishay Gal-Yam, Weizmann Institue of Science (PI)
  • Eran Ofek, Caltech (Caltech PI)
  • Filomena Bufano, INAF/Padova
  • Eddie Baron, University of Oklahoma
  • Stefano Benetti, INAF/Padova
  • Enrico Cappellaro, INAF/Padova
  • Peter Challis, CfA
  • Richard Ellis, Caltech
  • Alex Filippenko, Berkeley
  • Ryan Foley, Berkeley
  • Derek Fox, Penn State University
  • Robert Kirshner, CfA
  • Weidong Li, Berkeley
  • Doug Leonard, SDSU
  • Dan Maoz, Tel Aviv University
  • Tom Matheson, NOAO
  • Paolo Mazzali, INAF/Padova and MPA
  • Maryam Modjaz, Berkeley
  • Ken Nomoto, University of Tokyo
  • Dovi Poznanski, Berkeley
  • Josh Simon, Caltech
  • Massimo Turatto, INAF/Padova
  • Schuyler Van Dyk, Spitzer Science Center
  • Luca Zampieri, INAF/Padova

    GALEX The Benoziyo Center for Astrophysics The Caltech Core-Collapse Project (CCCP) Caltech Astronomy

    Constructed: April 2005, by: Avishay Gal-Yam , E-Mail: