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IAUC 5951: 1994D

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                                                  Circular No. 5951
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Telephone 617-495-7244/7440/7444 (for emergency use only)
TWX 710-320-6842 ASTROGRAM CAM     EASYLINK 62794505

     R. J. Cumming, Royal Greenwich Observatory (RGO); W. P. S.
Meikle, Imperial College; and T. R. Geballe, Joint Astronomy Center
(JAC), report:  "Near-infrared spectra (resolution 800-1200 km/s)
of SN 1994D were obtained by J. V. Wall (RGO), C. R. Jenkins (RGO),
Geballe, and D. M. Walther (JAC) with the U.K. Infrared Telescope
(+ CGS4) on Mar. 12.52 (J, H, K bands) and 13.51 UT (K only).  The
J-band spectrum shows a wide absorption feature centered at 1.052
microns and extending blueward as far as 1.036 microns.  If this is
due to a P-Cyg profile of He I 1.083-microns, it implies ejecta
velocities as high as 14 000 km/s.  On Mar. 12.52, the K-band
spectrum showed absorption features centred at 2.30, 2.33, 2.36, and
2.39 microns, all having a depth of 8-9 percent of the continuum.
We identify these features with first-overtone CO absorption at the
redshift of NGC 4526. The 2-0 band head at 2.300 microns is
unresolved at a resolution of 850 km/s.  The spectrum of Mar. 13.51
shows the 2-0 band at approximately the same strength and the band
head still unresolved, but the other CO bands have weakened
considerably.  An optical spectrum taken using ISIS on the William
Herschel Telescope on Mar. 10.14 by L. J. Smith (University College
London), M. Pettini and D. L. King (RGO), and C. Martin (Isaac
Newton Group) shows no evidence for narrow emission or absorption
in H-alpha associated with the supernova.  We judge that the origin
of the CO features must be intrinsic to the supernova system.  This
is supported by the change in their visibility.  The early appearance
and narrowness of the features imply that the CO lay above the ejecta."
     T. Shanks and S. M. Croom, University of Durham; and N. R.
Tanvir, Insititute of Astronomy, report:  "We obtained provisional
photometry (+/-0.01) of SN 1994D using the Jacobus Kapteyn 1.0-m
telescope:  Mar. 10.16 UT, U = 13.4, B = 13.7, V = 13.7, R = 13.6,
I = 13.7; 11.17, 12.8, 13.3, 13.3, 13.2, 13.2.  The B-V color is
close to the mean for type-Ia supernovae at maximum.  The supernova
appears 3"-4" to the north of a dust lane in this early-type galaxy.
These observations are consistent with a Virgo type-Ia supernova
nearing maximum in the next few days."
     P. M. Kilmartin and A. C. Gilmore, Mount John, report the
following equinox 2000.0 position for SN 1994D:  R.A. = 12h34m02s.37,
Decl. = +7o42'04".7 (corresponding 1950.0 position is R.A. =
12h31m29s.99, Decl. = +7o58'36".5).

1994 March 14                  (5951)            Daniel W. E. Green

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