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Dust extinction from SN host galaxies is currently one of the main unknowns in the observational measurement of SN rates, particularly at high redshifts. In an attempt to tackle the problem in a constructive way, during the last year of my PhD (2005) I developed a simple but yet effective Monte Carlo approach to estimate the expected SN extinction distribution and its dependence with dust properties and distribution. The method was presented in a paper (Riello & Patat 2006) and a later used to provide a statistical extinction correction for the SN rates measured by the STRESS project (see above and, soon, Botticella et al. 2007). Recently the literature has been quite hot on this topic, particularly with respect to the actual role played by dust rich environments like starburst, luminous and ultra-luminous infrared galaxies (LIRGs and ULIRGs respectively). The main concern seems to arise from the fact that the population of (U)LIRGs seems to increase with redshift and, given their high average extinction levels, it seems plausible that this effect would represent a serious bias for SN searches. Here you can really see two opposite attitudes in the literature. On one side you have people thinking that there is no way to discover SNe in such environments and therefore you should forget about measuring the star formation rate using SNe as tracers. On the other side, you find people acknowledging that there is a problem and trying hard to tackle it with the best the current technology can offer: infrared adaptive optics-powered instrumentation on large ground based telescopes and, a wee bit less effective, space based facilities.
Personally, I am more sympathetic with the second approach and, although I am not currently involved in any observational program, I plan to (this is one of those, “if only I have a little bit of time” -thing) investigate this issue by extending the Monte Carlo simulation code to describe the “nastier” (U)LIRGs environments.

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