SN 2011it in pgc67911 - 27 novembre 2011

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SN 2011it (A.R. 22 02 44.45, Dec. +31 41 49.1) scoperta il 27 novembre 2011 nella galassia PGC67911 (offset 5E 4N), magnitudine 16.9, tipo Ic.

SN scoperta da F. Ciabattari ed E. Mazzoni con il telescopio Newton da 50cm dell'Osservatorio di Monte Agliale (Lucca).

                                                  Electronic Telegram No. 2938
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director: Daniel W. E. Green; Hoffman Lab 209; Harvard University;
20 Oxford St.; Cambridge, MA 02138; U.S.A.
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SUPERNOVA 2011it IN PGC 67911 = PSN J22024445+3141491
F. Ciabattari and E. Mazzoni, Borgo a Mozzano, Italy, report their
discovery of an apparent supernova (mag 16.9) on unfiltered CCD images
(limiting magnitude 19.1) obtained on Nov. 27.78 and 29.79 UT with a 0.5-m
Newtonian telescope in the course of the Italian Supernovae Search Project.
The new object is located at R.A. = 22h02m44s.45, Decl. = +31d41'49".1 (equinox
2000.0; astrometry with respect to UCAC-2 stars), which is 5" east and 4" north
of the center of the galaxy PGC 67911. Nothing is visible at this position in
their images from this past September (limiting magnitude 19.1). The variable
was designated PSN J22024445+3141491 when it was posted at the Central Bureau's
TOCP webpage and is here designated SN 2011it based on the spectroscopic
confirmation reported below. Additional magnitudes for 2011it (from unfiltered
images unless noted otherwise): 1987 Aug. 26, [20.3 (Palomar Sky Survey, F
plate; via Ciabattari); 1989 July 8, [20.3 (Palomar Sky Survey, J plate; via
Ciabattari); 2011 Nov. 30.041, 16.5 (R. A. Koff, Bennett, CO, USA; Meade 0.25-m
f/10 reflector + Apogee AP-47p camera; limiting magnitude 18.9; position end
figures 44s.39, 48".0; UCAC3 reference stars; image posted at website URL
http://antelopehillsobservatory.org/SNpictures/PSNJ22024445+3141491final.jpg);
30.150, 16.7 (Joseph Brimacombe, Cairns, Australia; remotely using a 51-cm
RCOS telescope + STL11K camera + luminance filter at New Mexico Skies
Observatory near Mayhill, New Mexico; position end figures 44s.44, 48".5;
image posted at http://www.flickr.com/photos/43846774@N02/6433494795/).

L. Tomasella, A. Pastorello, S. Valenti, and S. Benetti, Istituto
Nazionale di Astrofisica, Osservatorio Astronomico di Padova, on behalf of a
larger collaboration, report that a spectrogram of PSN J22024445+3141491 =
SN 2011it, obtained on Nov. 29.96 UT with the Asiago 1.82-m Copernico
Telescope (+ AFOSC; range 350-820 nm; resolution 2.4 nm) by the Service
Telescope Operating Team, shows it to be a broad-line type-Ic supernova. The
best fit to this spectrum found by GELATO (Harutyunyan et al. 2008, A.Ap.
488, 383; available at URL https://gelato.tng.iac.es/login.cgi) suggests that
2011it is similar to SN 1998bw (Patat et al. 2001, Ap.J. 555, 900) and SN
2003jd (Valenti et al. 2008, MNRAS 383, 1485) between one and two weeks after
maximum light, adopting for the host galaxy a redshift of z = 0.015894 (de
Vaucouleurs et al. 1991, RC3 catalogue, via NED).


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

(C) Copyright 2011 CBAT
2011 December 5 (CBET 2938) Daniel W. E. Green