Central Bureau for Astronomical Telegrams
IAUC 3643: BROAD-LINE H-alpha SOURCES IN M31; 1981 UA; AM Her
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Circular No. 3643
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 617-864-5758
BROAD-LINE H-alpha SOURCES IN M31
H. Ford and R. Ciardullo, University of California at Los
Angeles; and G. Jacoby, Kitt Peak National Observatory, report the
discovery on Sept. 26 UT of four bright stellar H-alpha sources within 1
kpc of the center of M31. The objects do not appear on red plates
taken in 1979 with the 4-m telescope, nor on Einstein high-resolution-imager
photos of M31. Spectra obtained with the Lick 3-m telescope
on Oct. 4 and 5 reveal that the objects have steep Balmer decrements
and self-reversed H-alpha lines with widths ranging from 1900 to
2880 km/s (FWHM). The three brightest stars have broad weak lines
at ~ 463.3, ~ 501.8 and ~ 516.6 nm. The 1975.0 positions, offsets
from reference stars, line widths (FWHM, km/s) and H-alpha magnitudes
(mR = 18 is 2.45 x 10**-17 J m**-2 s**-1) are given below:
No. R. A. (1975) Decl. dR.A. dDecl. FWHM mR
1 0 40 56.88 +41 05 02.1 -1s53 +16"7 2750 18.7
2 0 41 18.72 +41 10 01.9 +3.50 -63.8 1900 16.6
3 0 41 36.29 +41 10 48.3 -0.74 +12.8 2700 17.0
4 0 41 43.99 +41 05 46.8 -0.73 +11.5 2880 18.0
In spite of similarities to classical novae, the number of objects,
spectral homogeneity at different magnitudes, and the absence of
forbidden lines and He I 587.6 nm suggest that they may not be
ordinary novae. Further observations should help establish the
nature of these unusual objects.
1981 UA
S. Dunbar, California Institute of Technology, communicates
precise positions for the observations on IAUC 3642 and for an Oct.
25 observation by C. Kowal. Calculations by C. M. Bardwell, Center
for Astrophysics, indicate that this is probably a Phocaea-type
object. Further details will appear on the Minor Planet Circulars.
AM HERCULIS
J. Mattei, AAVSO, reports the following visual magnitude
estimates: Sept. 2.1 UT, 14.6 (R. Weber, Ellis, KS); 7.21, 14.7, (M.
Heifner, Denver, CO); 9.08, 15.4 (E. Mayer, Barberton, OH); 27.1
14.8 (J. Volhard, Marathon, WI); 28.02, 15.0 (Mayer); Oct. 9.10,
13.5 (C. Scovil, Stamford, CT); 27.0, 13.8 (J. Morgan, Prescott, AZ).
1981 October 28 (3643) Daniel W. E. Green
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