S. Mattila, T. Dahlen, A. Efstathiou, E. Kankare, J. Melinder, A. Alonso-Herrero, M. A. Perez-Torres, S. Ryder, P. Vaisanen, G. Ostlin
We estimate the fraction of core-collapse supernovae that remain undetected by optical supernova searches due to obscuration by large amounts of dust in their host galaxies. This effect is especially important in luminous and ultraluminous infrared galaxies, which are locally rare but dominate the star formation at redshifts of z~1-2. We perform a detailed investigation of the supernova activity in the nearby luminous infrared galaxy Arp 299 and estimate that up to 83% of the supernovae in Arp 299 and in similar galaxies in the local Universe are missed by observations at optical wavelengths. For rest-frame optical surveys we find the fraction of supernovae missed due to high dust extinction to increase from the average local value of ~19% to ~38% at z~1.2 and then stay roughly constant up to z~2. It is therefore crucial to take into account the effects of obscuration by dust when determining supernova rates at high redshift and when predicting the number of core-collapse supernovae detectable by the future high-z surveys such as LSST, JWST, and EUCLID. For a sample of nearby core-collapse supernovae (distances 6-15 Mpc) detected during the last 12 years, we find a lower limit for the local core-collapse supernova rate of 1.5 +0.4/-0.3 x 10^-4 yr^-1 Mpc^-3, consistent with that expected from the star formation rate. Even more nearby, at distances less than ~6 Mpc, we find a significant increase in the core-collapse supernova rate indicating a local overdensity of star formation caused by a small number of galaxies that have each hosted multiple supernovae.
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http://arxiv.org/abs/1206.1314
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