[IAUC] CBET 612: 20060902 : SUPERNOVAE 2006el, 2006em, 2006ep, 2006eq

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                                                  Electronic Telegram No. 612
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://cfa-www.harvard.edu/iau/cbat.html


SUPERNOVAE 2006el, 2006em, 2006ep, 2006eq
     S. Blondin, M. Modjaz, R. Kirshner, and P. Challis,
Harvard-Smithsonian Center for Astrophysics, report that spectra
(range 350-740 nm) of SN 2006el (cf. CBET 605, IAUC 8741) and SN
2006ep (cf. CBET 609), obtained on Sept. 2.30 and 2.41 UT by P.
Berlind with the F. L. Whipple Observatory 1.5-m telescope (+ FAST),
show them to be both type-Ib supernovae around maximum light.
Cross-correlation with a library of supernova spectra shows that
2006el is most similar to the type-Ib supernova 2005bf (Tominaga et
al. 2005, Ap.J. 633, L97) at -4 days with respect to maximum
brightness, and that 2006ep is most similar to the type-Ib supernova
2005hg (cf. CBET 271) at -4.5 days.
     Blondin et al. add that that spectra (range 350-740 nm) of SN
2006em (cf. CBET 605, IAUC 8741) and SN 2006eq (cf. CBET 611),
obtained on Sept. 2.43 and 2.28 by Berlind, shows them to be both
type-Ia supernovae around maximum light.  Cross-correlation with a
library of supernova spectra shows that 2006em is most similar to the
subluminous supernova 1991bg at +2.7 days with respect to maximum
brightness.  Adopting a recession velocity of 5766 km/s for the host
galaxy (from Huchra et al. 1999, Ap.J. Suppl. 121, 287), the maximum
absorption in the Si II line (rest 635.5 nm) is blueshifted by roughly
10000 km/s.  SN 2006eq is similar to both the 1991T-like supernova
1999cl at +1.4 days with respect to maximum brightness and to the normal
supernova 1996X at +6.9 days, at an approximate redshift of 15000 km/s
(z = 0.05), consistent with that of the nearby putative host galaxy
mentioned in CBET 611.  This latter classification confirms the Ia
typing suggested by Bassett et al. (cf. CBET 611), which was based on
photometry alone.
     Comparison plots for all of the above supernovae can be seen at
the following URL:
http://www.cfa.harvard.edu/oir/Research/supernova/RecentSN.html


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2006 CBAT
2006 September 2                 (CBET 612)               Daniel W. E. Green