SUPERNOVA
2010il IN NGC 6922 AND VARIABLE STAR IN NGC 1511
J. Maza, M. Hamuy, R. Antezana, L. Gonzalez, P. Gonzalez,
S. Silva, G. Folatelli, R. Cartier, F. Forster, and
S. Marchi, Universidad de Chile; G. Pignata and M. Cifuentes,
Universidad Andres Bello; B. Conuel, Wesleyan University;
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, report the discovery of two apparent supernovae
-- one of which appears to be a luminous blue variable
in Aquila, from spectroscopy.
SN 2010il was at magnitude approximately 16.4 on an
unfiltered image taken on Sept. 29.10 UT with the 0.41-m
'PROMPT 5' telescope located at Cerro Tololo, and at
mag approximately 16.3 in an image taken on Sept. 30.11.
SN 2010il is located at R.A. = 20h29m53s.12 +/- 0".1,
Decl. = -2°11'24".7 +/- 0".1 (equinox 2000.0), which
is about 3".3 east and 3".9 north of the center of the
galaxy NGC 6922. Nothing is visible at this position
on archival images taken on Sept. 18.15 (limiting mag
18.5) and 10.09 (limiting mag 18.0).
The suspected supernova in NGC 1511 was at magnitude
approximately 15.9 on an unfiltered image taken on Sept.
29.25 UT with the 0.41-m 'PROMPT 4' telescope located
at Cerro Tololo, and at mag approximately 15.6 in an
image taken on Sept. 30.11; the variable is located
at R.A. = 3h59m38s.07 +/- 0".1, Decl. = -67°37'54".6
+/- 0".1 (equinox 2000.0), which is about 6".3 east
and 8".5 north of the center of the galaxy NGC 1511.
Nothing is visible at this position on archival images
taken on Sept. 6.39 and 18.38 (limiting mag 18.0).
N. Morrell, Las Campanas Observatory, Carnegie Supernova
Project; and I. Botti and P. Lopez, Universidad de Chile,
report optical spectroscopy (range 364-920 nm) of the
CHASE candidates in NGC 1511 and NGC 6922 obtained on
Sept. 30 UT with the Las Campanas 2.5-m du Pont telescope
(+ WFCCD). The variable in NGC 1511 shows a blue continuum
with strong superimposed Balmer emission lines, suggesting
this may be the outburst of a luminous blue variable.
SN 2010il is a type-Ib/c supernova similar to SN 1999ex
around maximum light; cross-correlation with a library
of supernova spectra using the Supernova Identification
code (Blondin and Tonry, 2006, Ap.J. 666, 1024) provides
an excellent match for 2010il to the spectrum of SN
1999ex at maximum brightness.
NOTE: These 'Central Bureau Electronic Telegrams' are
sometimes superseded by text appearing later in the
printed IAU Circulars.
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