Circular No. 8376
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 2004di IN UGC 10097
    Independent discovery reports of an apparent supernova have
been received from M. Armstrong (Rolvenden, U.K., 0.35-m reflector)
and R. Arbour (South Wonston, U.K., 0.3-m reflector).  Armstrong
reports the new object's position as R.A. = 15h55m41s.02, Decl. =
+47o51'49".1 (equinox 2000.0), which is approximately 23" west and
11" south of the center of UGC 10097; Arbour's measured position
end figures are 40s.98, 48".8.  Unfiltered CCD magnitudes of SN
2004di:  July 14 UT, [19.0 (Armstrong); 18.922, [17.5 (Arbour);
26.903, 17.0 (Armstrong); 27.891, 17.0 (Armstrong); 27.911, 16.8
(Arbour).  Nothing was visible at this position on Palomar Sky
Survey images from 1989 and 1993 (red limiting mag 20.8; blue
limiting mag 22.5).


SUPERNOVA 2004dg
    N. Elias de la Rosa, S. Benetti, H. Navasardyan, F. Bufano, A.
Harutyunyan, G. Blanc, and M. Turatto, Osservatorio Astronomico di
Padova; A. Pastorello, Osservatorio Astrofisico di Arcetri; and E.
Cappellaro, Osservatorio Astronomico di Capodimonte, report that
inspection of a spectrogram, obtained on July 21.87 UT with the
Asiago 1.8-m telescope (+ AFOSC; range 355-780 nm, resolution 2.4
nm), indicates that SN 2004dg (cf. IAUC 8375) is a type-II
supernova, about 1 month after explosion.  The spectrum is
dominated by P-Cyg lines of H I, Ca II H and K, Fe II, and Ti II.
A narrow H_alpha feature (from a nearby H II region) is visible on
the top of the broad emission, from which the observers deduce a
recession velocity of about 1720 km/s, which in turn is
substantially higher than the galaxy's recession velocity given by
NED (1359 km/s).  The expansion velocities deduced from the H_alpha
and H_beta absorptions are about 8270 and 6760 km/s, respectively.


SUPERNOVAE 2004ct AND 2004dh
    T. Matheson, P. Challis, and R. Kirshner, Harvard-Smithsonian
Center for Astrophysics, report that a spectrum (range 340-730 nm)
of SN 2004ct (cf. IAUC 8361), obtained by M. Calkins on July 22.28
UT with the F. L. Whipple Observatory 1.5-m telescope (+ FAST),
shows it to be a type-Ia supernova several weeks past maximum.  A
spectrogram of SN 2004dh (cf. IAUC 8375), obtained by Calkins on
July 23.44, shows it to be a type-II supernova.  The spectrum
consists of a blue continuum with P-Cyg lines of hydrogen.
Adopting the NED recession velocity of 5794 km/s for the host
galaxy, the expansion velocity derived from the minimum of the
H_beta line is 9500 km/s.

                      (C) Copyright 2004 CBAT
2004 July 27                   (8376)            Daniel W. E. Green