[IAUC] CBET 1232: 20080129 : SUPERNOVAE 2008Q AND 2008R

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                                                  Electronic Telegram No. 1232
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS en CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT en CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html


SUPERNOVAE 2008Q AND 2008R
     V. Stanishev, Physics Department, Stockholm University, reports that a
spectrum of 2008Q (cf. CBET 1228), obtained with the Nordic Optical Telescope
(+ ALFOSC; range 350-900 nm) by T. Pursimo on Jan. 29.83 UT, shows an early
type-Ia supernova, likely about a week before maximum light.  The blue-shift
of the minimum of the Si II 635.5-nm absorption line is about 13500 km/s,
assuming a recession velocity for the host galaxy, NGC 524, of 2379 km/s
(Simien and Prugniel 2000, A.Ap. Suppl. 145, 263).  The ratio of the depth of
the Si II 635.5-nm and 597.2-nm absorptions (cf. Nugent et al. 1995, Ap.J.
455, L148) is about 0.27 +/- 0.04.  A high-velocity component is visible in
the Ca II infrared triplet absorption.

     Stanishev adds that a spectrum of 2008R (cf. CBET 1230), obtained as
above on Jan. 29.84 UT, shows it to be a type-Ia supernova near maximum light.
The spectrum is similar to that of SN 2004eo (cf. IAUC 8406) two days after
maximum light (cf. Pastorello et al. 2007, MNRAS 377, 1531).  The ratio of the
depths of the Si II 635.5-nm and 597.2-nm absorptions (cf. Nugent et al. 1995,
Ap.J. 455, L148) is about 0.57 +/- 0.07, and the pseudo-equivalent widths of
these two lines (as defined in Branch at al. 2006, PASP 118, 560) are 11.6 and
4.5 nm, respectively.  Taking into account the recession velocity of the host
galaxy, NGC 1200 (4048 km/s; Wegner et al. 2003, A.J. 126, 2268), the blue-
shift of the minimum of the Si II 635.5-nm absorption line is about 10500 km/s.
     Corrigendum.  On CBET 1230, line 10, FOR  52s.72,  READ  53s.72,


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                         (C) Copyright 2008 CBAT
2008 January 29                  (CBET 1232)              Daniel W. E. Green