On the hydrogen emission from the type Ia supernova SN 2002ic

The discovery of SN 2002ic and subsequent spectroscopic studies have led to the surprising finding that SN 2002ic is a Type Ia supernova with strong ejecta-circumstellar interaction. Here we show that nearly 1 year after the explosion the supernova has become fainter overall, but the Ha emission has brightened and broadened dramatically compared to earlier observations. We have obtained spectropolarimetry data that show that the hydrogen-rich matter is highly aspherically distributed. These observations suggest that the supernova exploded inside a dense, clumpy, disklike circumstellar environment.