Electronic Telegram No. 398 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://cfa-www.harvard.edu/iau/cbat.html SUPERNOVAE 2006aa, 2006ac, 2006ad The "Nearby Supernova Factory" collaboration (N. Blanc, Y. Copin, E. Gangler, and G. Smadja, Institut de Physique Nucleaire de Lyon; P. Antilogus, S. Gilles, R. Pain, and R. Pereira, Laboratoire de Physique Nucleaire et de Haute Energies de Paris; G. Aldering, S. Bailey, S. Bongard, D. Kocevski, B. C. Lee, S. Loken, P. Nugent, S. Perlmutter, R. Scalzo, R. C. Thomas, L. Wang, and B. A. Weaver, Lawrence Berkeley National Laboratory, Berkeley; E. Pecontal and G. Rigaudier, Centre de Recherche Astronomique de Lyon; R. Kessler, Kavli Institute for Cosmological Physics, Chicago; and C. Baltay, D. Rabinowitz, and A. Bauer, Yale University) reports the discovery of a supernova (mag approximately 18.9, calibrated to R) in NEAT images obtained on Feb. 8.3 UT using the QUEST II camera on the Palomar Oschin 48-inch telescope (cf. CBET 263). SN 2006ad is located at R.A. = 9h07m43s.11, Decl. = +12o03'06".5 (equinox 2000.0). A spectrogram (range 320-1000 nm), obtained on Feb. 10.5 with the Supernova Integral Field Spectrograph (SNIFS) on the University of Hawaii 2.2-m telescope, shows 2006ad to be a type-II supernova at an approximate redshift of z = 0.03, as measured from the peak of its H-alpha emission. SNIFS spectra of supernovae 2006aa and 2006ac (cf. IAUC 8669) were taken on Feb. 10.5 and 10.6 UT, respectively. SN 2006aa is a type-IIn supernova at an approximate redshift (measured from its H-alpha emission peak) of z = 0.02, consistent with that of its host (NGC 3947, at z = 0.0207; from de Vaucouleurs et al. 1991, Third Reference Cat. of Bright Galaxies, ver. 3.9, via NED). SN 2006ac is a young type-Ia supernova, its spectrum similar to that of SN 1994D about nine days before maximum, at a redshift consistent with that of its host (NGC 4619, at z = 0.0231, de Vaucouleurs et al. 1991, via NED). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2006 CBAT 2006 February 11 (CBET 398) Daniel W. E. Green