This SN was discovered by LOSS (IAUC 8387) on Aug 12, 2004, and was absent on Aug. 9, indicating it was discovered less than 3 days after explosion.
The host galaxy UGC 11683 is at z=0.016762 (NED).
Keck spectrum obtained by Fassnacht and analyzed by Li and collaborators (IAUC 8388) on Aug 13, 2004, indicates it is a very young type IIn SN.
Later spectroscopy leads Filippenko et al. to claim this is a SN II-P (!) (IAUC 8411)
Preliminary P60 light curves: