Central Bureau for Astronomical Telegrams
IAUC 4500: 1987A; 1986n
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Circular No. 4500
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
TWX 710-320-6842 ASTROGRAM CAM Telephone 617-495-7244/7440/7444
SUPERNOVA 1987A IN THE LARGE MAGELLANIC CLOUD
Ames Research Center and M. Cohen, University of California,
Berkeley, report: "Infrared spectra of SN 1987A from 4 to 13 microns
were obtained using the Kuiper Airborne Observatory on the nights
of Nov. 10, 12 and 14 UT. The spectrum is dominated by strong
emission in the 1-0 band of CO, several forbidden fine-structure
lines of Ni, Ar and Co, and the hydrogen Humphries, Pfund and
Brackett series. Preliminary line fluxes for the strongest emission
lines are (in units of 10**-17 W cm-2): H[4-5], 14; H[5-6], 4.5;
H[6-7], 1.2; Ni II 6.62 microns, 4.1; Ar II 6.98 microns, 2.3; Co II 10.52
microns, 2.1. Some of the weaker emission features in the spectrum have
been identified tentatively as the 1-0 SiO molecular band and Co
III, Ni I and Fe III lines. The continuum emission level has
decreased substantially (by a factor of about 3) since Apr. 21."
H. Moseley, NASA Goddard Space Flight Center; W. Glaccum, R.
Loewenstein, R. Silverberg, E. Dwek and J. Graham report: "We have
made spectrophotometric detection of SN 1987A over a wide range of
far-infrared wavelengths varying from 16 to 64 microns. The
observations were carried out aboard the Kuiper Airborne Observatory on
Nov. 17 and 19 using the Goddard 24-channel spectrophotometer. In
the short-wavelength configuration (16-29 microns, resolution 0.6 microns)
the supernova was strongly detected in all channels. The lowest
point in the spectrum was about 8 Jy near 21 microns. Many lines have been
detected and have been tentatively associated with the following
transitions: Fe II (17.9, 24.5 and 25.98 microns), Fe III (22.9 microns), S
III (18.7 microns) and S IV (18.28 microns). The presence of these lines,
combined with the absence of S I (25.2 microns) and Fe I (24.1 microns),
suggests that the ionization state of the emitting matter is
higher than expected. In the long-wavelength configuration, which
covered the 35-70 microns spectral range with a spectral resolution of
1.8 microns, we detected the continuum level with an intensity of 2 +/-
0.5 Jy near 40 microns and of 4 +/- 1 Jy near 50 microns. We tentatively
identify a line detected around 63.2 microns with the O I transition."
Visual magnitude estimates by A. C. Beresford, Adelaide, S.
Australia: Nov. 23.58 UT, 6.1; 24.48, 6.1.
COMET SORRELLS (1986n)
Total visual magnitude estimate by J. Kobayashi, Kumamoto,
Japan (0.31-m reflector): Sept. 18.47 UT, 13.3.
1987 November 25 (4500) Brian G. Marsden
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