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IAUC 8381: 2004dn; N Sco 2004 No. 2

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                                                  Circular No. 8381
Central Bureau for Astronomical Telegrams
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SUPERNOVA 2004dn IN UGC 2069
     Further to IAUC 8377, J. Graham and W. Li report the LOSS
discovery of an apparent supernova on an unfiltered KAIT image
taken on Aug. 2.48 UT (mag about 17.5).  The new object was
confirmed on an earlier image taken on July 29.42 (mag about 18.5).
SN 2004dn is located at R.A. = 2h35m37s.30, Decl. = +37o37'54".2
(equinox 2000.0), which is 0".5 west and 26".1 south of the nucleus
of UGC 2069.  A KAIT image taken on Jan. 23.21 showed nothing at
this position (limiting mag about 19.5).  SN 1961P was located 36"
south of the galaxy's nucleus.
     F. Patat and G. Pignata, European Southern Observatory; and S.
Benetti, Istituto Nazionale di Astrofisica, on behalf of the ERTN
(see IAUC 7954 and 8344 -- not IAUC 8341, as cited incorrectly on
IAUC 8378, 8379), report that a fully reduced spectrum (range
320-900 nm; resolution 1.6 nm) of SN 2004dn, obtained on Aug. 5.15
UT by J. Aceituno at the Calar Alto Observatory 2.2-m telescope (+
CAFOS), shows it to be a type-Ic supernova.  The spectrum is very
similar to those of the type-Ic SNe 1991A and 1994ai (Asiago-ESO
supernova archive, unpublished; IAUC 5155, 6120), a few days before
maximum light.  Photospheric expansion velocities, deduced from the
absorption minima of Si II 635.5-nm and O I 777.4-nm, are about
9600 km/s and 10700 km/s, respectively.  The recession velocity of
UGC 2069 at the supernova position, measured from the unresolved
H_alpha and H_beta arising in the underlying H II region, is about
3950 km/s.

     H. Yamaoka, Kyushu University, forwards the following position
for this object (cf. IAUC 8380) measured by K. Itagaki from an
unfiltered CCD image taken on Aug. 5.475 UT (with poor sky
conditions; the new object was at mag 8.0):  R.A. = 17h29m18s.81,
Decl. = -31o46'01".5 (equinox 2000.0).  This appears nearly
identical with the location of a very red catalogued star whose
USNO-A2.0 position end figures are 18s.818, 01".68 (blue mag 19.7,
red mag 17.4), and whose 2MASS position end figures are 18s.82,
01".5 (J = 14.4).  Yamaoka adds that a low-resolution spectrum of
the new object, taken by M. Fujii, Bisei, Okayama, Japan, on Aug.
5.49, shows broad H_alpha and H_beta emissions with P-Cyg profiles
(H_alpha FWHM = 3000 km/s), along with several Fe II and O I
emission lines -- suggesting that the object is a classical nova.
W. Liller, Vina del Mar, Chile, writes that the nova was fainter
than mag 11.0 on a Technical Pan film exposed (with an orange
filter) on July 19.40.

                      (C) Copyright 2004 CBAT
2004 August 5                  (8381)            Daniel W. E. Green

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