Central Bureau for Astronomical Telegrams
IAUC 6049: V1974 Cyg; V407 Cyg
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Circular No. 6049
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)
V1974 CYGNI
L. Rosino, P. Rafanelli, T. Iijima, and E. Esenoglu, Asiago
Astrophysical Observatory, report: "CCD spectra of the nova V1974
Cyg, obtained in June and July with the 1.82-m Asiago telescope at
Mt. Ekar, indicate a further decrease of the degree of ionization.
The strongest emission lines observed in the optical spectrum and
their approximate intensities relative to H-beta (absolute flux
31.5 x 10E-14 erg cmE-2 sE-1) are now, in order of decreasing
strength: [Ne V] at 342.6 nm, 19.9; [O III] at 500.7 nm, 17.8; H-
alpha (possibly blended with [N II]), 5.2; [Ne III] at 386.9 nm,
2.8; He II at 468.6 nm, 1.2. Other emission lines, with intensities
from 0.55 to 0.1, observed in the spectra are: H-delta + N III;
H-gamma; [O III] at 436.3 nm; He I at 587.6, 667.8, and 706.5 nm;
N III at 464.0 nm; [Fe VI] at 567.7 nm; [Fe VII] at 608.7 nm; [O I]
at 630.0 nm; and [O II] at 732-733 nm. No further traces have been
found of the coronal lines observed in 1993. The approximate FWHM
expansion velocity of the ejecta is of the order of 1600 +/- 100
km/s. The strongest emission lines in the spectrum display typical
saddle-shaped profiles."
V407 CYGNI
U. Munari, Asiago Astrophysical Observatory; A. Bragaglia and
M. D. Guarnieri, Bologna Astronomical Observatory (BAO); G. Sostero
and A. Lepardo, Associazione Friulana Astronomia e Meteorologia;
and B. F. Yudin, Moscow Astronomical Institute (MAI), communicate:
"The symbiotic Mira-type variable V407 Cyg (= Nova Cyg 1936) is
currently undergoing an unexpected bright and active phase (cf.
Munari et al. 1990, MNRAS 242, 653). Photoelectric photometry
secured with the 0.91-m telescope of the Catania Astronomical
Observatory on Aug. 4 and 6 gives V = 13.0, B-V = +1.0, U-B = 0.0.
CCD spectra (range 390-780 nm; 1-nm resolution) obtained with the
1.5-m BAO telescope (+ BFOSC) on Aug. 7.0 UT show the Mira absorption
continuum overwhelmed by a hot continuum shortward of 540 nm.
Hydrogen, He I, and forbidden O III lines (never seen in the Asiago
1986-1993 low-resolution spectra) are in strong emission. JHKL
photometry secured in July with the 1.25-m MAI Crimean telescope
confirms that the Mira variable is now close to minimum brightness
during its 745-day pulsation cycle."
1994 August 8 (6049) Daniel W. E. Green
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