Detailed Multiwavelength Study of the Late-Time Evolution of SN 1978K

SN 1978K is a remarkable Type IIn supernova that remains bright at Xray throughradio wavelengths 35 years after its explosion. Our ongoing multiwavelengthobservations probe the dense medium that was ejected by the progenitor star,possibly a Luminous Blue Variable. While the radio flux has dropped steadily,the Xray and UV/optical fluxes remained surprisingly constant for a decade.However, our most recent XMM observation in 2013 June reveals a significantfading. Here we request a 100 ksec observation to continue the detailed spectralevolution study. This will serve as a pathfinder for younger Type IInsupernovae. As secondary science, we will obtain data on the ULXs X1 and X2,and the other luminous sources in NGC 1313. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]