Central Bureau for Astronomical Telegrams
IAUC 6790: 1997eg; GS 1354-64; eta Car
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Circular No. 6790
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 1997eg IN NGC 5012
S. Nakano, Sumoto, Japan, reports the discovery by Masakatsu
Aoki, Tsukioka-cho, Toyama, of an apparent supernova (mag 15.6) on
ten frames taken around Dec. 4.85 UT and three frames taken on Dec.
5 with a 0.43-m f/6 reflector (+ unfiltered CCD). The limiting
magnitude on Dec. 4 was about 18.5. SN 1997eg is located at R.A. =
13h11m36s.73, Decl. = +22o55'29".4 (equinox 2000.0), which is 4".1
west and 33".1 north of the center of NGC 5012. There is no object
at this position on Aoki's earlier frames taken on fifteen nights
between 1996 Apr. 22 and 1997 Aug. 11, or on the Digital Sky Survey.
There is a star of mag 13.9 located about 5" east of SN 1997eg.
GS 1354-64
W. Heindl, P. Blanco, D. Gruber, M. Pelling, D. MacDonald, D.
Marsden, and R. Rothschild, Center for Astrophysics and Space
Sciences, University of California at San Diego, report: "Pointed
observations of GS 1354-64 (IAUC 6772, 6774, 6775, 6779, 6781) with
the RXTE/HEXTE on Nov. 22.40, Dec. 5.21, and 12.81 UT yield fluxes
of 150, 150, and 130 mCrab (15-200 keV), respectively. In all
cases, the spectrum can be described by an exponentially-cutoff
power law with photon index 1.0 +/- 0.1 and an e-folding energy of
about 60 keV. Although GS 1354-64 is in outburst, this spectrum is
similar to blackhole candidates in the low (hard) state. The
spectrum in the HEXTE band is not consistent with a single power
law. However, fitting only in the band 30-100 keV gives photon
indices of 2.0 +/- 0.1, somewhat harder than the value (2.7)
reported with BATSE (IAUC 6774) for these times. Because the
source remains active, additional observations at x-ray and other
wavelengths continue to be desirable."
eta CARINAE
D. F. Lopes, Observatorio Nacional; and A. Damineli, Instituto
Astronomico e Geofisico da Universidade de Sao Paulo, communicate:
"eta Car has entered a new spectroscopic event phase; CCD spectra
collected on Dec. 10 at the coude focus of the 1.6-m telescope of
the Laboratorio Nacional de Astrofisica show the complete fading of
the high-excitation lines. The excellent agreement between
observations and predictions (Damineli et al. 1997, New Astron. 2,
107, and IAUC 6768) supports the hypothesis that the 5.52-yr cycle
in these events is periodic."
(C) Copyright 1997 CBAT
1997 December 17 (6790) Daniel W. E. Green
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