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The Type Ia Supernova Rate in Radio and Infrared Galaxies from the CFHT Supernova Legacy Survey

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 نشر من قبل Melissa Graham
 تاريخ النشر 2009
  مجال البحث فيزياء
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We have combined the large SN Ia database of the Canada-France-Hawaii Telescope Supernova Legacy Survey and catalogs of galaxies with photometric redshifts, VLA 1.4 GHz radio sources, and Spitzer infrared sources. We present eight SNe Ia in early-type host galaxies which have counterparts in the radio and infrared source catalogs. We find the SN Ia rate in subsets of radio and infrared early-type galaxies is ~1-5 times the rate in all early-type galaxies, and that any enhancement is always <~ 2 sigma. Rates in these subsets are consistent with predictions of the two component A+B SN Ia rate model. Since infrared properties of radio SN Ia hosts indicate dust obscured star formation, we incorporate infrared star formation rates into the A+B model. We also show the properties of SNe Ia in radio and infrared galaxies suggest the hosts contain dust and support a continuum of delay time distributions for SNe Ia, although other delay time distributions cannot be ruled out based on our data.



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