Central Bureau for Astronomical Telegrams
IAUC 3649: V1343 Aql; H0139-68
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Read IAUC 3650
Circular No. 3649
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
V1343 AQUILAE
B. Margon and S. Anderson, University of Washington; and S.
Grandi, University of California, Los Angeles, report: "The 164-d
precessional period of V1343 Aql (= SS 433) continues to change in
a complex manner. Recent spectroscopic observations confirm the
prediction of Margon et al. (IAUC 3626) that the very large rate of
change observed in the first few years of data, dP/dt = -0.009 +/- 0.001,
must moderate. If one considers only data obtained during the past
16 months, a rate of change of opposite sign is now derived, dP/dt =
+0.016 +/- 0.004. More data will be needed to characterize the analytic
form of this second period derivative. Pending such observations,
it will be difficult to predict accurately more than a few
months in advance Doppler-shift values of V1343 Aql."
H0139-68
P. C. Agrawal and A. R. Rao, Tata Institute of Fundamental
Research; G. R. Riegler, Jet Propulsion Laboratory; and A. J. Pickles
and N. Visvanathan, Mount Stromlo and Siding Spring Observatories,
telex: "We have discovered a new variable soft x-ray source, H0139-68,
and its optical identification with an AM-Her-like cataclysmic
variable. The x-ray source, originally detected with the low-energy
detectors of the HEAO A-2 experiment, was found to be highly variable
over periods as short as 3 hr, with maximum flux of ~ 6 x
10**-14 J m**-2 s**-1 in the band 0.15-0.4 keV. No flux was detected
above 0.4 keV, indicating a very soft spectrum (i.e., < 3 x 10**6 K).
Observation of the H0139-68 error box with the image proportional
counter of the Einstein Observatory confirmed a bright variable
x-ray source and yielded the following position (equinox 1950.0): R.A. =
1h39m36s, Del. = -68o07'57". During IPC observations lasting for 1800
s, the source count-rate decreased from ~ 2 cts/s to ~ 1 ct/s.
There is indication of flickering on a timescale of 20 s or less.
The x-ray source has been identified with a star at R.A. = 1h39m37s.5,
Decl. = -68o08'32", which is within 36" of the x-ray source position.
Time-resolved spectrophotometry of the star over 3 hr with the PCA
on the Mt. Stromlo 1.9-m telescope shows a variation between V =
14.9 and V = 16.4 with a period of 110 min. Spectra are dominated
by emission lines of H I, He I 447.1 and 587.5 nm, He II 468.5 and
541.1 nm, C III and N III 464.7 nm throughout the period. The mean
radial-velocity curve of the emission lines varies from +340 to
-150 km/s, leading the light curve by 0.1 period. The continuum
changes with phase and is reddest at maximum."
1981 December 14 (3649) Daniel W. E. Green
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