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IAUC 6775: 1997dt; GS 1354-64; PSR J0633+1746

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                                                 Circular No. 6775
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 1997dt IN NGC 7448
    Q. Y. Qiao, Y. L. Qiu,  W. D. Li, and J. Y. Hu, Beijing
Astronomical Observatory (BAO); and A. Esamdin, Urumqi Astronomical
Station, report the discovery of a supernova (mag about 15.3) on
unfiltered CCD images taken with 0.6-m telescope on Nov. 22.44 UT.
The supernova is located at R.A. = 23h00m02s.93, Decl. =
+15o58'50".9 (equinox 2000.0), which is 9".3 west and 1".0 north of
the center of NGC 7448.  SN 1997dt was confirmed on images taken on
Nov. 21.48 (mag about 15.4).  Unfiltered CCD images of the same
field taken on Nov. 14 show no star at the position of the
supernova (limiting mag about 18.5).  A low-dispersion spectrum of
the supernova, obtained on Nov. 22.50 by A. Esamdin, J. Y. Wei, L.
Cao (BAO), and Q. S. Gu (Nanjing University) with the 2.16-m
telescope at Xinglong Station, shows this to be a type-Ia supernova
near maximum.  The spectrum displays a strong Si II 615-nm
absorption feature.  The recession velocity, derived from the
narrow H-alpha emission line, is 2192 km/s.


GS 1354-64
     A. J. Castro-Tirado, Laboratorio de Astrofisica Espacial y
Fisica Fundamental, Madrid; S. Ilovaisky, Observatoire de Haute-
Provence; and H. Pedersen, Copenhagen University Observatory,
write:  "Following the detection of GS 1354-64 by Rossi XTE (IAUC
6772) and BATSE (IAUC 6774), B- and R-band images were obtained
with the New Technology Telescope at the European Southern
Observatory on Nov. 22.35 UT by J.-F. Gonzalez, M. Pizarro, J.
Miranda, and H. Boehnhardt.  The optical counterpart (cf. Kitamoto
et al. 1990, Ap.J. 361, 590) is being detected in a bright state.
Preliminary magnitudes:  R = 16.9 +/-0.1, B = 18.1 +/- 0.2."


PSR J0633+1746
     Yu. P. Shitov and V. M. Malofeev, Pushchino Radio Astronomy
Observatory, Lebedev Physical Institute, communicate:  "With our
colleagues O. I. Malov and V. D. Pugachev, we observed Geminga at
low frequencies with the east-west arm of Wide-Band Cross-type
Radio Telescope DKR-1000 (area about 40 000 m**2) during July-
October and detected radio emission of the pulsar PSR J0633+1746
with period 0.237 s at 41 and 61 MHz (cf. IAUC 6559).  The flux
density is about 300 mJy at 41 MHz, and the spectral index > 2.5,
suggesting a mean flux density < 30 mJy at 102.5 MHz.  The width of
the integrated profile at 50 percent of maximum intensity is about
half the period at both frequencies."

                      (C) Copyright 1997 CBAT
1997 November 22               (6775)            Daniel W. E. Green

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