Studying supernovae in the near-ultraviolet with the nasa swift UVOT instrument

Observations in the near- and mid-ultraviolet (NUV: 2000-3500) performed with the NASA Swift UVOT instrument have revealed that optically-normal SNe Ia feature NUV-optical color evolution that can be divided into NUV-blue and NUV-red groups, with roughly one-third of the observed events exhibiting NUV-blue color curves. Combined with an apparent correlation between NUVblue events and the detection of unburned carbon in the optical spectra, the grouping might point to a fundamental difference within the normal SN Ia classfication. Recognizing the dramatic temporal evolution of the NUV-optical colors for all SNe Ia, as well as the existence of this subdivision, is important for studies that compare nearby SNe Ia with intermediate or high-z events, for the purpose of the cosmological utilization of SNe Ia. SN 2011fe is shown to be of the NUVblue groups, which will be useful towards interpretation of the gamma-ray line results from the INTEGRAL SPI campaign on SN 2011fe.