Circular No. 8378

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                                                  Circular No. 8378




Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 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)
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Phone 617-495-7440/7244/7444 (for emergency use only)


SUPERNOVA 2004dj IN NGC 2403
     F. Patat, European Southern Observatory; S. Benetti and A.
Pastorello, Istituto Nazionale di Astrofisica; and A. V. Filippenko,
University of California, Berkeley, on behalf of the ERTN (see IAUC
8341), report that a fully reduced spectrum (range 320-900 nm;
resolution 1.2 nm) of SN 2004dj (cf. IAUC 8377), obtained on Aug.
3.17 UT by J. Aceituno at the Calar Alto Observatory 2.2-m
telescope (+ CAFOS), shows it to be a normal type-II-P supernova,
very similar to SN 1999em, about 3 weeks after explosion (Leonard
et al. 2001, Ap.J. 553, 861; Hamuy et al. 2001, Ap.J. 558, 615).
Besides a very-well-developed hydrogen Balmer series, lines from Na
I, Fe II, and Ca II are clearly visible, all with P-Cyg profiles.
The Na I D feature is possibly blended with He I 587.6-nm.  The
spectrum also shows an unresolved absorption at 589.7 nm,
identified as interstellar Na I D, most likely generated by
intervening material in the host galaxy.  The equivalent width of
this feature, 0.11 nm, corresponds to E(B-V) about 0.18 mag.  The
photospheric expansion velocities, deduced from the minima of
absorption troughs of various lines, are as follows:  H_alpha, 6700
km/s; H_beta, 5500; Fe II 516.9-nm, 4150; Fe II 501.8-nm, 3800; Fe
II 492.4-nm, 3850 km/s.


COMETS C/2001 Q4 (NEAT) AND C/2003 K4 (LINEAR)
     C. E. Woodward and M. S. Kelley, University of Minnesota; and
D. H. Wooden, Ames Research Center, NASA, report 8-13-micron
spectrophotometry of these comets using the NASA Ames HIFOGS
spectrometer at the Infrared Telescope Facility 3-m reflector:
"Weak silicate-feature emission (cf. IAUC 8360, 8339) is present in
the 10-micron spectra of C/2001 Q4 on July 28.24 UT, when the
observed N-band magnitude (3" circular aperture) was 3.7 +/- 0.4.
Preliminary analysis of the featureless 10-micron spectra of C/2003
K4 suggests that large amorphous carbon and silicate grains (radius
approximately > 0.7 micron) dominate the coma.  Further to IAUC
8361, no structure attributable to crystalline silicates was
evident.  The observed N-band magnitudes (3" circular aperture) of
C/2003 K4 were:  July 26.24, 3.6 +/- 0.4; 27.24, 3.4 +/- 0.2."
     Visual total-magnitude estimates of C/2003 K4:  June 27.11 UT,
7.6 (J. J. Gonzalez, Leon, Spain, 7x50 binoculars); July 12.94, 6.8
(A. Baransky, Bucha, Ukraine, 10x50 binoculars); 16.96, 7.1 (A.
Kammerer, Malsch, Germany, 9x63 binoculars); 20.49, 6.8 (Y. Nagai,
Nagano, Japan, 7x35 binoculars); 28.93, 6.7 (A. Diepvens, Balen,
Belgium, 20x50 binoculars); Aug. 1.92, 6.5 (J. G. de S. Aguiar,
Campinas, Brazil, 11x80 binoculars).

                      (C) Copyright 2004 CBAT
2004 August 3                  (8378)            Daniel W. E. Green