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IAUC 3324: H 2155-304; 2A 0311-227

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IAUC number 

                                                  Circular No. 3324
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


H 2155-304
     J. L. Greenstein, J. B. Oke and R. A. Wade, Hale Observatories,
report observations of the optical candidate for H 2155-304 (cf.
IAUC 3279, 3309) obtained with the multichannel spectrophotometer
at the Cassegrain focus of the 500-cm reflector.  Power-law indices
alpha, monochromatic flux densities f_nu (at 5480 A; f_nu ~ nu**alpha) and the
corresponding V magnitudes are as follows:

       1978 UT         alpha           log f_nu              V
       Oct. 23.2       0.68            (-25.04)            (14.0)
       Nov.  2.1       0.65             -24.88              13.6
       Dec. 24.1       0.52 +/- 0.10    -24.68 +/- 0.02     13.1

     The flux on Oct. 23.2 is uncertain because of poor seeing at high
airmass.  The power-law fits describe the spectra to better than 10
percent from 3400 A to 10 000 A; single-temperature blackbodies do
not provide acceptable fits to the data.  The spectra (40 A resolution
in the blue, 80 A in the red) show no emission or absorption
lines; an equivalent width of 2 A in the blue or 4 A in the red
would have been easily detectable.  There is no sign of the Balmer
jump in emission or in absorption.

     S. E. Persson, also of Hale Observatories, reports the following
infrared magnitudes, obtained on 1978 Dec. 21.0 UT at Las Campanas
Observatory: J = 11.78, H = 11.23, K = 10.59 (errors +/- 0.03).
The corresponding values of log f_nu are -24.53, -24.50 and -24.44,
giving a spectral index of about 0.4 for the infrared.


2A 0311-227
     W. A. Hiltner, University of Michigan, communicates the following
report by F. Boley, M. Johns and S. Maker: "Spectroscopic observations
at the McGraw-Hill Observatory of a probable optical counterpart
of 2A 0311-227, the eastern star of an 18"-separation
double located at R.A. = 3h12m00s, Decl. = -22o46'.8 (equinox 1950.0),
identified independently by Griffiths et al. (1978, Bull. Am. Astron.
Soc. 10, 662) and by G. Williams from the Curtis-Schmidt objective-prism
plate collection, reveal that it is a spectroscopic binary
with a period of 81 +/- 5 min.  Preliminary radial-velocity measurements
of H-beta and He II 4686 A emission give a peak-to-peak amplitude
of nearly 800 km/s, variable with time and spectral feature.  Equivalent
widths of H-beta and He II vary with the above period, greatest
intensity occurring at negative velocities."


1979 February 5                (3324)              Brian G. Marsden

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