[IAUC] CBET 452: 20060329 : SUPERNOVA 2006be IN IC 4582

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                                                  Electronic Telegram No. 452
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 2006be IN IC 4582
     F. Patat, European Southern Observatory (ESO); A. Boselli, Laboratoire
d'Astrophysique de Marseille; S. Benetti and H. Navasardyan, Osservatorio
Astronomico di Padova, Istituto Nazionale di Astrofisica; M. Dennefeld,
Insitut d'Astrophysique de Paris; D. Baade, ESO; and L. Wang, Lawrence
Berkeley Laboratory, report that spectrograms, obtained on Mar. 29.01 UT
with the 1.93-m telescope at Haute-Provence Observatory (+ Carelec
spectrograph; range 370-780 nm, resolution 0.7 nm) and on Mar. 29.30 with
the ESO Very Large Telescope (+ FORS1 in polarimetric mode; range 340-840
nm, resolution 1.2 nm), show that SN 2006be (cf. CBET 449, IAUC 8693) is a
type-II supernova.  The spectrum is dominated by broad P-Cyg lines of
hydrogen, Ca II, and Fe II.  The intensities of the Na I D-He I 587.6-nm
feature and of the feature visible on the blue wing of the H-alpha
absorption suggest a phase of about two weeks past explosion (Pastorello
et al. 2006, MNRAS, submitted).  The expansion velocity, deduced from the
H-beta absorption feature, is about 8100 km/s (the recession velocity of
the parent galaxy is assumed to be 2145 km/s, from de Vaucouleurs et al.
1991, Third Reference Cat. of Bright Galaxies, via NED).  Narrow galactic
and interstellar absorption lines of Na I D are present with equivalent
widths of 0.04 and 0.07 nm, respectively, suggesting that the light from
the supernova could suffer significant extinction.  Preliminary
spectropolarimetric analysis of FORS1 data shows a mild linear
polarization, at the level of 1 percent, on the minimum of the H-alpha
absorption through.

     G. C. Anupama, D. K. Sahu, and G. Uday Kumar, Indian Institute of
Astrophysics, report that a spectrogram (range 350-740 nm) of SN 2006be,
obtained on Mar. 28.95 UT with the Indian Astronomical Observatory's 2-m
Himalayan Chandra Telescope (+ HFOSC), shows it to be a young type-II
supernova.  The spectrum contains P-Cyg profiles of Balmer series.
Adopting a redshift of z = 0.007155 (de Vaucouleurs et al. 1991, Third
Reference Catalogue of Bright Galaxies, Version 3.9), the absorption in
H-alpha is blueshifted by about 9000 km/s.  The spectrum is very similar
to that of SN 1999em about 15-20 days past maximum (Leonard et al. 2002,
PASP 114, 35).


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                         (C) Copyright 2006 CBAT
2006 March 29                    (CBET 452)               Daniel W. E. Green