[IAUC] CBET 1508: 20080916 : SUPERNOVAE 2008fa, 2008ff, AND 2008fl

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                                                  Electronic Telegram No. 1508
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVAE 2008fa, 2008ff, AND 2008fl
     N. Morrell and M. Stritzinger, on behalf of the Carnegie Supernova
Project, report that they obtained spectra (range 400-1070 nm) of 2008fa (cf.
CBET 1475), 2008ff (cf. CBET 1488), and 2008fl (cf. CBET 1498) with the Las
Campanas Observatory Magellan I (Baade) telescope (+ IMACS) on Sept. 15.06,
15.03, and 15.01 UT, respectively.  All three objects are type-Ia supernovae.
Using the "Supernova Identification" code (SNID; Blondin and Tonry 2007,
Ap.J. 666, 1024), Morrell and Stritzinger find 2008fa to be similar to
supernova 1991bg around three weeks past maximum; adopting a host-galaxy
recession velocity of 4626 km/s for NGC 6722 (de Vaucouleurs et al. 1991,
Third Reference Catalogue of Bright Galaxies, version 3.9), they measure an
expansion velocity of 7800 km/s from the minimum of the Si II 635.5-nm
absorption line.  SN 2008ff appears to be a normal type-Ia supernova around
2 to 3 weeks past maximum; using a recession velocity of 5758 km/s (Memzies
et al. 1989, A.J. 97, 1576) for the host galaxy, PGC 64319, the Si II
635.5-nm absorption feature yields an expansion velocity of roughly 12500
km/s.  SN 2008fl is a type-Ia supernova around maximum light; the spectrum
displays a blue continuum superimposed on a series of prominent P-Cyg
features including, among others, Si II and S II.  Adopting for NGC 6805 a
recession velocity of 5970 km/s (Jones et al. 2004, The 6dF Galaxy Survey
data release 1), find Si II 635.5-nm is found to be blue-shifted by -10500
km/s.  SNID provides good matches for 2008fl with a number of normal type-Ia
supernovae between one week before and after maximum.
     Regarding the announcement report of 2008fl on CBET 1498, G. Pignata
writes that they incorrectly reported the magnitudes of 2008fl; following
are their corrected magnitudes:  Sept. 7.19 UT, 17.1 +/- 0.2; 8.17, 17.2
+/- 0.2.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2008 CBAT
2008 September 16                (CBET 1508)              Daniel W. E. Green