[IAUC] CBET 421: 20060307 : SUPERNOVA 2006X IN NGC 4321

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                                                  Electronic Telegram No. 421
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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SUPERNOVA 2006X IN NGC 4321
        J. T. Lauroesch, Northwestern University; A. P. S. Crotts, Columbia
University; J. Meiring and V. P. Kulkarni, University of South Carolina;
D. M. Meyer, Northwestern University; and D. E. Welty and D. G. York,
University of Chicago, report that high-resolution spectrograms of SN 2006X
(cf. 8667, 8680), obtained with the Magellan Clay Telescope (+ MIKE
spectrograph) on Feb. 13.35 and 23.25 UT, show unusually strong redshifted
CN B-X (0,0) violet band absorption consistent with an origin in the
interstellar gas in NGC 4321 (= M100).  A preliminary analysis of these
data yields an extraordinarily large equivalent width (0.0090 +/- 0.0010
nm) for the CN R(0) 387.46-nm line, the EW being greater than published
observations of this line through any Galactic interstellar cloud (e.g.,
Crutcher 1985 Ap.J. 288, 604; Roth and Meyer 1995, Ap.J. 441, 129;
Pan et al. 2004, Ap.J. Suppl. 151, 313).  Sightlines in our Galaxy with
similarly large CN columns (e.g., HD 29647; Crutcher 1985) have visual
extinctions (A_V) greater than 3 magnitudes.  Other interstellar lines
detected in M100 include strong saturated lines of Na I, Ca II, and K I,
as well as modest absorption due to CH, CH+, and several diffuse
interstellar bands.


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                         (C) Copyright 2006 CBAT
2006 March 7                     (CBET 421)               Daniel W. E. Green