2003IAUC.8043....4F

Filippenko and Chornock add: "Keck spectra obtained as above reveal that the object is a peculiar type-Ia supernova not long after maximum brightness. It is spectroscopically similar to the subluminous SN 1991bg (e.g., Filippenko et al. 1992, A.J. 104, 1543), but with some distinct differences. For example, its Ti II trough around 420 nm is not as strong as that of SN 1991bg, while the 460-nm emission feature is much stronger. The expansion velocities of the two objects are very similar, about 10000 km/s."