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IAUC 7829: V838 Mon; 2002aq, 2002at

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                                                  Circular No. 7829
Central Bureau for Astronomical Telegrams
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
URL http://cfa-www.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)

     D. K. Lynch, R. J. Rudy, S. Mazuk, and C. Venturini, The
Aerospace Corporation, report 0.8-2.5-micron spectroscopy of V838
Mon on Jan. 28.16 UT:  "Using the Aerospace Near-Infrared Imaging
Spectrometer on the Lick 3-m telescope, we observed a continuum
peaking near 1 micron (photospheric temperature of roughly 3000 K),
with significant broad structure between 0.8 and 1.2 microns, and a
slightly elevated continuum near 1.6 microns, suggestive of the H-
opacity minimum.  Emission lines present included H I Paschen and
weak Brackett lines, many with strong P-Cyg profiles, indicating an
expansion velocity of around 500 km/s.  Also present were the Ca II
infrared triplet with strong absorption and weak emission, deep CO
first-overtone band absorption near 2.3 microns, and a number of
the same lines reported by Geballe et al. (IAUC 7796), most of them
with P-Cyg profiles; V838 Mon appears to have brightened in the
infrared by about 30 percent since Jan. 12.33, and the emission
lines have also strengthened."
     N. D. Morrison, University of Toledo, reports a change to
higher excitation in the spectrum of V838 Mon since Jan. 26 (IAUC
7812):  "CCD echelle spectra (resolving power 26 000; nine 7-nm
regions in the yellow and red), were taken with the Ritter
Observatory 1-m telescope on Feb. 5.2, 6.1, 8.1, and 9.1 UT by K.
S. Bjorkman, A. Miroshnichenko, and myself (and reduced by J. P.
Wisniewski).  The only stellar features detected in this range were
Fe II (531.6 nm), Na I (588.9 and 589.5 nm), Si II (634.7 and 637.1
nm), and H_alpha, all with P-Cyg profiles.  H_alpha is mainly in
emission, has a mean net equivalent width of -3.2 nm, and has
electron scattering wings extending at least 3 nm on either side of
the line center.  Its absorption component has a mean heliocentric
blue-edge velocity of -300 km/s, and the mean absorption centroid
velocity is -200 km/s.  Significant strengthening of the Na I
absorption and emission components and weakening of the Si II
absorption component took place between Feb. 6 and 8."

SUPERNOVAE 2002aq AND 2002at
     A. V. Filippenko, University of California, Berkeley; and A.
J. Barth, California Institute of Technology, report:  "Inspection
of a CCD spectrum (range 320-1000 nm), obtained on Feb. 14 UT with
the Keck-I telescope, reveals that SN 2002aq (IAUC 7813) is of type
II, probably within one month past maximum brightness; the H_alpha
line has a well-developed P-Cyg profile.  A spectrum of SN 2002at
(IAUC 7821) is essentially featureless and quite blue; perhaps the
object is a very young type-II supernova."

                      (C) Copyright 2002 CBAT
2002 February 14               (7829)            Daniel W. E. Green

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