Electronic Telegram No. 1355 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://www.cfa.harvard.edu/iau/cbat.html SUPERNOVAE 2008ca AND 2008cb M. M. Kasliwal and R. Quimby, California Institute of Technology (CIT); M. H. V. Kerkwijk, University of Toronto; S. R. Kulkarni, CIT; and D. A. Howell, University of Toronto, report the discovery of two apparent supernovae during a pilot run for the proposed "Coma and Virgo Exploration for Transients" project, using the Canada-France-Hawaii Telescope (+ MegaPrime camera). The redshifts tabulated below are the Sloan Digital Sky Survey redshifts (photometric for 2008ca and spectroscopic for 2008cb) for the visible, presumed-host galaxies in each case; the tabulated magnitudes are in the r' band (bandwidth 121.9 nm, centered at 628.2 nm; transmission curve posted at http://www.cfht.hawaii.edu/Instruments/Filters/curves/9601.png). SN 2008 UT R.A. (2000.0) Decl. Mag. Host-galaxy redshift 2008ca Mar. 10 12 29 01.28 +12 22 18.8 20.7 0.123 2008cb Mar. 10 12 31 18.90 + 8 23 18.1 21.2 0.165 Additional r' magnitudes for 2008ca: Mar. 1, [22.5; 5, 22.4. Additional r' magnitudes for 2008cb: Mar. 2, [22.5; 4, 22.5; 5, 22.0. SN 2008cb is situated on a bar of a spiral galaxy. Both host galaxies have apparent sizes of < 30". The Mar. 1 and 2 images were used as reference images for subtraction because they are the earliest epochs available; the limiting magnitude is approximately 22.5 in all the images. The authors are not pursuing spectroscopic follow-up because supernovae are not the primary focus for this project. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2008 CBAT 2008 April 24 (CBET 1355) Daniel W. E. Green