The Distance to SN 1999em in NGC 1637 from the Expanding Photosphere Method
The Distance to SN 1999em in NGC 1637 from the Expanding Photosphere Method
We present 30 optical spectra and 49 photometric epochs sampling the first 517 days after discovery of supernova (SN) 1999em and derive its distance through the expanding photosphere method (EPM). SN 1999em is shown to be a Type IIāplateau (IIāP) event, with a photometric plateau lasting until about 100 days ā¦