La SN 1999dk dans UGC 1087
Voici l'extrait de l'IAUC N°7237
SUPERNOVA 1999dk IN UGC 1087
M. Modjaz and W. D. Li, University of California at Berkeley, on behalf of the Lick Observatory Supernova Search (cf. IAUC 6627, 7126), report the discovery with the 0.8-m Katzman Automatic Imaging Telescope (KAIT) of an apparent supernova in UGC 1087. The supernova was discovered and confirmed on unfiltered CCD images taken on Aug. 12.5 UT (mag about 16.7) and Aug. 13.5 UT (mag about 16.4). The new object is located at R.A. = 01h31m26s.92, Decl. = +14o17'05".7 (equinox 2000.0), which is 4".1 east and 26".2 north of the nucleus. A KAIT image of the same field on Aug. 7.5 UT (limiting mag about 18.0) showed nothing at the position of the supernova.
Et un extrait de l'IAUC 7238
SUPERNOVAE 1999dh AND 1999dk
M. E. Salvo, Padova Astronomical Observatory, S. Benetti, Telescopio Nazionale Galileo, P. Kjaergaard and T. R. Greve, Copenhagen University Observatory, report spectroscopic confirmation of supernovae 1999dh and 1999dk. A spectrum (range 350-900 nm; resolution 3.4 nm) of SN 1999dk,taken with the Nordic Optical Telescope 2.54-m telescope + ALFOSC at La
Palma on Aug. 15.06 UT, shows the very blue continuum and the characteristic features of a normal type Ia supernova about two weeks before maximum light. From the broad P-Cyg line, usually attributed to 635.5-nm Si II, an expansion velocity for the Si II shell of about 16 200 km/s is derived. From the Ca II H and K doublet an expansion velocity of about 29 400 km/s for the C ~II shell is also derived.