Electronic Telegram No. 280 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 2005ht, 2005hv, 2005hy, 2005hz, 2005id, 2005ij, 2005is-2005ka Further to CBET 268, 272, and 277, J. Barentine, Apache Point Observatory (APO); B. Bassett, University of Portsmouth (UP); A. Becker, University of Washington; R. Bender, University of Munich (UM); M. Bremer, University of Bristol; H. Brewington, APO; F. DeJongh, Fermilab; J. Dembicky, APO; D. L. DePoy, Ohio State University (OSU); B. Dilday, University of Chicago (UC); M. Doi, University of Tokyo (Tokyo); A. Edge, University of Durham; E. Elson, South African Astronomical Observatory (SAAO); J. Frieman, Fermilab and UC; P. Garnavich, University of Notre Dame; A. Goobar, Stockholm University; M. Harvanek, APO; T. Gueth and J. Holtzman, New Mexico State University; U. Hopp, UM; W. Kollatschny, Goettingen University; K. Konishi, Tokyo; J. Krzesinski, APO; D. Lamenti, San Francisco State University; H. Lampeitl, Fermilab; R. Kessler, UC; B. Ketzeback, APO; K. Konishi, Tokyo; D. Long, APO; J. Marriner, Fermilab; J. L. Marshall, OSU; R. McMillan, APO; J. Mendez, University of Barcelona (UB); G. Miknaitis, Fermilab; T. Morokuma, Tokyo; R. Nichol, UP; K. Pan, APO; J. L. Prieto, OSU; M. Richmond, Rochester Institute of Technology; A. Riess, Space Telescope Science Institute; R. Romani, Stanford University (SU); K. Romer, University of Sussex; P. Ruiz-Lapuente (UB); M. Sako (SU); D. Schneider, Penn State University; M. Smith, UP; S. Snedden, APO; M. Subbarao, UC and Adler Planetarium; N. Takanashi and K. Tokita, Tokyo; K. van der Heyden, SAAO; C. Wheeler, University of Texas; and N. Yasuda, Tokyo, on behalf of the Sloan Digital Sky Survey II collaboration, report the discovery of 35 new supernovae on multiple g, r, and i images taken with the SDSS 2.5-m telescope at Apache Point Observatory by the SDSS observing team. Spectroscopy of SNe 2005is-2005jj was obtained with the Subaru, Hobby-Eberly, William Herschel, ARC, and MDM telescopes, showing thirteen of them to be of type Ia and the remaining five (SNe 2005is, 2005jb, 2005je, 2005jf, and 2005jj) to be probable type-Ia supernovae. Spectroscopy of SNe 2005jk-2005jr was obtained by A. Filippenko and R. Foley (University of California, Berkeley) on the Keck telescope on the night of Nov. 4, showing 2005jk-2005jp to be type-Ia supernovae and SNe 2005jq and 2005jr to be of type IIn. Spectroscopy of SNe 2005js-2005ka was obtained with the Hobby-Eberly Telescope, showing eight of them to be of type Ia and the ninth (SN 2005jx) to be a probable type-Ia supernova. The discovery magnitudes tabulated below are all g magnitudes unless followed by an asterisk, in which case they are r magnitudes due to non-detection in g on the discovery date. Spectroscopic redshifts are given in the column labelled z where available. Peak g magnitudes and dates (all 2005) are estimated from fits to the multi-band light curves. SN Discov. R.A. (2000.0) Decl. Mag. z Estimated Peak Date Date Mag. 2005is Oct. 12 0 21 44.97 - 0 19 30.1 20.8 0.17 Oct. 17 20.3 2005it Oct. 12 1 04 45.70 + 0 30 50.1 22.0 0.31 Oct. 2 21.6 2005iu Oct. 20 20 20 15.60 + 0 13 02.6 21.5 0.09 Nov. 2 19.0 2005iv Oct. 20 20 31 44.67 + 0 14 41.1 21.9 0.30 Oct. 21 21.7 2005iw Oct. 20 22 29 17.76 - 0 05 32.5 22.4 0.27 Oct. 20 22.2 2005ix Oct. 21 20 41 55.88 + 1 05 31.2 22.0 0.25 Nov. 2 20.9 2005iy Oct. 21 21 24 51.95 + 0 23 08.2 22.5 0.39 Oct. 8 22.3 2005iz Oct. 21 21 52 16.47 + 0 16 01.5 21.4 0.20 Oct. 18 21.2 2005ja Oct. 21 23 55 52.64 + 0 52 37.2 22.1 0.32 Oct. 25 21.7 2005jb Oct. 23 22 36 03.21 - 0 22 04.5 22.6 0.38 Oct. 30 22.4 2005jc Oct. 23 0 45 24.41 + 1 04 32.1 22.0 0.21 Nov. 2 20.7 2005jd Oct. 23 2 17 06.20 + 0 32 05.4 22.0* 0.32 Oct. 30 21.6 2005je Oct. 24 2 35 26.62 + 1 04 29.6 20.9 0.09 Nov. 5 19.0 2005jf Oct. 24 3 33 40.76 - 0 06 43.5 22.0 0.30 Oct. 24 21.8 2005jg Oct. 25 23 01 02.97 - 0 12 26.5 22.5 0.30 Oct. 28 22.2 2005jh Oct. 25 23 20 04.43 - 0 03 19.7 21.3 0.11 Nov. 3 19.6 2005ji Oct. 27 0 17 18.34 - 0 15 26.1 21.4 0.22 Nov. 5 20.8 2005jj Oct. 28 20 56 44.66 + 0 24 30.0 22.9 0.37 Oct. 25 22.6 2005jk Oct. 20 1 45 59.43 + 1 11 45.4 21.3 0.16 Oct. 26 20.8 2005jl Oct. 23 21 32 56.12 - 0 41 59.2 22.2 0.18 Nov. 4 20.6 2005jm Oct. 26 21 52 18.98 + 0 28 18.9 23.4 0.20 Nov. 4 21.3 2005jn Oct. 26 0 19 00.83 - 0 16 53.4 21.7 0.32 Oct. 29 21.4 2005jo Oct. 26 3 28 21.68 - 0 19 33.9 22.2 0.23 Nov. 4 21.3 2005jp Oct. 28 2 09 50.39 - 0 03 42.3 22.1 0.21 Nov. 3 21.2 2005jq Oct. 30 20 29 47.68 + 1 08 33.7 21.3 0.23 Nov. 5 21.0 2005jr Oct. 30 1 00 12.37 + 0 20 26.9 22.1 0.30 Nov. 2 21.6 2005js Oct. 20 1 34 41.52 - 0 36 19.3 20.6 0.08 Oct. 20 20.7 2005jt Oct. 30 2 50 40.16 - 0 03 57.5 23.2 0.36 Nov. 2 23.1 2005ju Oct. 28 2 36 28.04 + 0 30 40.6 22.5 0.26 Nov. 4 21.7 2005jv Oct. 28 2 40 50.12 + 0 59 35.3 22.8 0.42 Nov. 3 22.5 2005jw Oct. 25 20 40 19.25 - 0 00 25.8 22.2 0.37 Oct. 27 22.2 2005jx Oct. 25 21 34 20.17 - 0 40 54.1 22.4 0.21 Oct. 25 22.4 2005jy Oct. 20 23 13 51.60 + 1 15 25.2 22.1 0.27 Oct. 25 21.7 2005jz Oct. 11 1 31 27.06 - 0 37 53.8 22.4 0.25 Oct. 18 21.4 2005ka Oct. 20 22 13 55.96 + 1 05 11.4 22.1 0.32 Oct. 12 22.0 In addition, redshifts for several type-Ia supernovae reported in CBET 268 are now measured: 2005ht, z = 0.19; 2005hv, 0.17; 2005hy, 0.13; 2005hz, 0.12; 2005id, 0.19; and 2005ij, 0.11. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2005 CBAT 2005 November 10 (CBET 280) Daniel W. E. Green