[vsnet-grb-info 5520] XRF 080109 / SN 2008D: spectroscopic evolution

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  7184
SUBJECT: XRF 080109 / SN 2008D: spectroscopic evolution
DATE:    08/01/15 17:45:10 GMT
FROM:    Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center  <malesani at astro.ku.dk>

D. Malesani (DARK), J. Sollerman (DARK and Univ. Stockolm), J.P.U. 
Fynbo, C.C. Thoene, D. Xu, J. Hjorth, G. Leloudas, P.M. Vreeswijk, D.J. 
Watson (DARK), P. Jakobsson (Univ. Herfordshire), T. Augusteijn, C. 
Villforth, S.-M. Niemi (NOT), report on behalf of a larger collaboration:

We observed SN 2008D with the Nordic Optical Telescope on Jan 13.05 and 
Jan 15.16 UT. Spectra were acquired covering the range 3700-7500 AA.

The spectra have evolved when compared to earlier epochs (Malesani et 
al., GCN 7169; Blondin et al., CBET 1205; Valenti et al., CBET 1205). 
The spectrum of Jan 15 now appears similar to that of the normal type-Ic 
SN 1994I a few days before maximum (Clocchiatti et al. 1996, ApJ, 462, 
462). In particular, the spectral features are clearly narrower than 
those of SN 1998bw and SN 2006aj at comparable epochs.

A plot of the NOT spectrum of Jan 15, compared with that of SN 1994I 
dereddened by A_V = 0.7 mag, is shown at the following URL:

http://www.astro.ku.dk/~malesani/GRB/080109/spec_Jan15.png