
Electronic Telegram No. 2661
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge,
MA 02138,
U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html
SUPERNOVA
2011ah IN ESO 364-12 = PSN J05535077-3244442
J. Maza, M. Hamuy, R. Antezana, L. Gonzalez, R. Cartier,
F. Forster, S. Silva, F. Carrasco, P. Sanchez, and C.
Hervias, Universidad de Chile; G. Pignata and M. Cifuentes,
Universidad Andres Bello; B. Conuel, Wesleyan University;
G. Folatelli, IPMU, University of Tokyo; and D. Reichart,
K. Ivarsen, J. Haislip, A. Crain, D. Foster, M. Nysewander,
and A. LaCluyze, University of North Carolina at Chapel
Hill, on behalf of the CHASE project (which is part
of the Millennium Center for Supernova Science collaboration),
report the discovery of an apparent supernova (mag approximately
16.0) on an unfiltered image taken on Feb. 5.15 UT with
the 0.41-m 'PROMPT 1' telescope located at Cerro Tololo.
The new object (which was designated PSN J05535077-3244442
when posted on the Central Bureau's TOCP webpage, and
which is here designated SN 2011ah based on the spectroscopic
report below) is located at R.A. = 5h53m50s.77 +/- 0".2,
Decl. = -32o44'44".2 +/- 0".2 (equinox 2000.0),
which is about 15".6 west and 7".2 south of
the center of the galaxy ESO 364-12. Nothing is visible
at this position on archival images taken on 2010 Dec.
31.25 (limiting mag 18.5) and 2011 Jan. 16.19 (limiting
mag 18.0).
J. Anderson and
F. Forster, Universidad de Chile; G. Pignata, Universidad
Andres Bello; and G. Folatelli, University of Tokyo,
on behalf of the Millennium Center for Supernova Science,
report that they have obtained a spectrum (range 420-900
nm) of PSN J05535077-3244442 = SN 2011ah on Feb. 17.1
UT with the Magellan Baade 6.5-m telescope (+ IMACS)
at Las Campanas Observatory. The spectrum indicates
that 2011ah is a type-Ia supernova around a week after
maximum; comparison with template spectra using the
"Supernova Identification" code (SNID; Blondin
and Tonry 2007, Ap.J. 666, 1024) provides a close
match to that of SN 1996C at eight days after maximum
light. Adopting a host-galaxy recession velocity of
8094 km/s (Jones et al. 2009, 6DF Galaxy Survey Data
Release 3) as reported via the NASA/IPAC Extragalactic
Database, an expansion velocity of 12000 km/s is calculated
from the absorption minimum of the Si II 635.5-nm
line.
NOTE: These 'Central Bureau Electronic
Telegrams' are sometimes superseded by text appearing
later in the printed IAU Circulars.
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2011
Febrary 28 |
(C)
Copyright 2010 CBAT
(CBET 2661) |
Daniel
W. E. Green |
Volver
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