Central Bureau for Astronomical Telegrams
IAUC 5544: N Cyg 1992; 1992d
The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).
Read IAUC 5545
Circular No. 5544
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Telephone 617-495-7244/7440/7444 (for emergency use only)
TWX 710-320-6842 ASTROGRAM CAM EASYLINK 62794505
MARSDEN@CFA or GREEN@CFA (.SPAN, .BITNET or .HARVARD.EDU)
NOVA CYGNI 1992
Y. J. Pendleton, Ames Research Center, NASA, communicates: "R.
Gehrz, C. Kaminski, N. Jennerjohn, S. Sandford, L. Allamandola, and
I report near-infrared spectroscopy of Nova Cyg 1992 in a 2".7 beam
using the Cooled Grating Array Spectrometer of the NASA Infrared
Telescope Facility. The spectrum (range 2.9-3.77 microns,
resolution 0.018 micron) taken over a 30-min interval on May 29.6 UT
showed several prominent emission features. Subsequent high-
resolution observations of those features (taken on May 30.6 and May
31.5 over 60- and 90-min intervals, respectively; resolution 0.004
micron) were made with half-channel grating shifts to obtain a
complete spectrum. Preliminary analysis shows a fairly smooth
continuum due to free-free emission on which are superposed several H
emission lines (Pf-epsilon, Pf-delta, and Pf-gamma) and some
unidentified emission lines (near 3.08 microns). The lines are
resolved and preliminary analyses indicate the following intrinsic
line FWHM values: Pf-gamma (3.739 microns), 2400 km/s; Pf-delta
(3.29 microns), 3000 km/s. The former is quite symmetric while the
latter is asymmetric. Pf-gamma is the strongest line and relative
strengths are Pf-gamma/Pf-delta about 1.35 and Pf-gamma/Pf-epsilon
about 2. There appear to be two lines blended in the 3.08-micron
region and the strength of these features is comparable to the Pf-
delta line. There is no evidence for infrared coronal emission at
this time. There is, however, evidence of line splitting in the
Pf-epsilon line (3.038 microns) at locations up to 7 wavenumbers on
either side of the line center. Line splitting may arise from a
multiple, toroidal, or clumpy shell structure in the ejecta."
R. Gehrz, T. J. Jones, and G. Lawrence, University of
Minnesota, report the following infrared magnitudes obtained with a
bolometer system at O'Brien Observatory: May 19.4 UT, J = 7.0, H =
7.2, K = 6.6, L = 5.7, M > 4.9 (3-sigma detection), N > 1.2; May
29.4, L > 4.1.
Further visual magnitude estimates forwarded by the AAVSO:
June 9.92 UT, 8.4 (P. Schmeer, Bischmisheim, Germany); 10.35, 8.5
(P. Collins, Boulder, CO); 10.98, 8.4 (B. H. Granslo, Fjellhamar,
Norway); 11.35, 8.7 (Collins).
COMET TANAKA-MACHHOLZ (1992d)
Total visual magnitude estimates (cf. IAUC 5531): June 3.21
UT, 8.5 (R. Donner, Santa Barbara, CA, 0.25-m reflector); 5.99, 9.1
(H. Luthen, Hamburg, Germany, 0.20-m reflector); 11.31, 8.8 (J. E.
Bortle, Stormville, NY, 0.32-m reflector).
1992 June 15 (5544) Daniel W. E. Green
Read IAUC 5545
Our Web policy. Index to the CBAT/MPC/ICQ pages.
