[IAUC] CBET 1681: 20090203 : SUPERNOVAE 2008iu AND 2008iv

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                                                  Electronic Telegram No. 1681
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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CBAT en CFA.HARVARD.EDU (science)
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SUPERNOVAE 2008iu AND 2008iv
     Further to CBET 1676, A. J. Drake, S. G. Djorgovski, R. Williams, A.
Mahabal, and M. J. Graham, California Institute of Technology; M. Catelan,
Pontificia Universidad Catolica; and E. C. Beshore and S. M. Larson, Lunar and
Planetary Laboratory, University of Arizona, report the CRTS discovery of
two apparent supernovae in unfiltered CSS images:

SN        2008 UT         R.A. (2000.0) Decl.      Mag.      Offset
2008iu    Oct. 30.36    4 36 55.20  - 0 21 35.6    18.1   0".4 E, 0".7 S
2008iv    Dec. 22.50    9 39 49.91  + 7 03 47.8    18.7   16".0 E, 9".3 S

     The Palomar 1.52-m reflector (+ Gunn filters) was used for follow-up
photometry with Gunn g, r, and i filters, as listed below (otherwise,
magnitudes unfiltered CSS images, where stated).
     The host galaxy of 2008iu, SDSS J043655.17-002136.3, has Gunn magnitudes
u = 22.5, g = 22.6, r = 22.1, i = 21.8, and z = 22.1.  Additional magnitudes
for 2008iu:  2008 Mar. 8.11 UT, [20.4 (CSS); Oct. 6.49, 18.1 (CSS); Oct. 9.48,
18.1 (CSS); Oct. 31.49, g = 18.1, r = 18.2, i = 18.0; Nov. 19.39, 18.3 (CSS);
Dec. 3.36, 18.3 (CSS); Dec. 29.27, 18.6 (CSS); 2009 Jan. 20.24, 18.8 (CSS).
A noisy spectrum (range 380-520 nm) of 2008iu was obtained on Dec. 4.15 with
the SMARTs 1.5m telescope.  Cross-correlation with a library of supernova
spectra using the "Supernova Identification" code (SNID; Blondin and Tonry
2007, Ap.J. 666, 1024) indicates that 2008iu is most similar to the type-Ic
supernova 1998bw at 34 days after maximum light; this is consistent with the
peak time derived from the light curve.
     The host galaxy of 2008iv, SDSS J093948.83+070357.1, has Gunn magnitudes
u = 18.7, g = 17.8, r = 17.4, i = 17.2, and z = 17.1, and redshift z = 0.019.
Additional magnitudes for 2008iv:  2008 Dec. 7.45, [20.0 (CSS); 2009 Jan.
17.53, 18.6 (CSS).


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2009 CBAT
2009 February 3                  (CBET 1681)              Daniel W. E. Green