2006CBET..699....1B

S. Blondin, M. Modjaz, R. Kirshner, and P. Challis, Harvard-Smithsonian Center for Astrophysics, report that a spectrum (range 350-740 nm) of 2006lc (cf. CBET 693), obtained on Oct. 26.19 UT by M. Calkins with the F. L. Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a type-Ib/c supernova around maximum light. The spectrum exhibits conspicuous lines of He I (rest 447.1, 587.6, 667.8 nm), as well as a strong absorption near 620 nm due to Si II (rest 635.5 nm). Cross-correlation with a library of supernova spectra shows that 2006lc is most similar to the type-Ib supernova 2005hg (cf. CBET 271) at -2 days from maximum light, and to the type-Ib/c supernova 1999ex (see Hamuy et al. 2002, A.J. 124, 417) at maximum. SN 2006lc is thus an example of an intermediate case between supernova types Ib and Ic. A comparison plot can be seen at the following URL: http://cfa-www.harvard.edu/oir/Research/supernova/spectra/sn2006lc_comp.gif. Adopting a recession velocity of 4894 km/s (from Falco et al. 2000, "The Updated Zwicky Catalogue", vol. 1), the maximum absorption in the Si II (rest 635.5 nm) line is blueshifted by roughly 7400 km/s.