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IAUC 4116: GX 349+2; R CrB; IAUC 4106-4107

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IAUC number 

                                                  Circular No. 4116
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 617-495-7244/7440/7444


GX 349+2
     B. A. Cooke, Leicester University; L. Stella, EXOSAT Observatory;
and T. Ponman, Birmingham University, communicate: "Analysis
of 5 hr of a 50-hr EXOSAT medium-energy observation of GX 349+2
during Aug. 31-Sept. 2 has confirmed the existence of quasiperiodic
oscillations in the x-ray flux (IAUC 4101).  Although the x-ray
flux from this source varies between a quiescent level and a flaring
state during which the flux may double, the oscillations were
detected only when the source flux was less than ~ 1.4 times the
quiescent level.  At these times the power spectrum displayed both
a broad peak (significance > 50-sigma), with a definite turnover toward
lower frequencies, and a low-frequency excess.  These data were
well fitted by a combined Gaussian and power law, giving a peak
centroid at 5 Hz, a FWHM of 15 Hz, and an rms pulsation amplitude
of ~ 2 percent.  The rms amplitude of the low-frequency excess,
integrated over the range 0.1-64 Hz, was ~ 3 percent.  Attempts to
fit simple shot noise models produced substantially worse fits."


R CORONAE BOREALIS
     D. Bohme, Nessa, German Democratic Republic, reports the
following photoelectric magnitudes using an 0.25-m Cassegrain
telescope: Aug. 11.87 UT, V = 5.97, B-V = +0.47; 20.86, 5.92, +0.54;
21.84, 5.89, +0.60; 28.82, 6.01, +0.77; 29.87, 6.06, +0.64; Sept.
2.84, 6.11, +0.66.

     Visual magnitude estimates: Sept. 14.17, 6.8 (P. Collins,
Cardiff, CA); 15.04, 6.8 (F. Glenn, Stamford, CT); 15.86, 6.9 (K.
Medway, Southampton, England); 16.9, 7.0 (M. Verdenet, Bourbon-
Lancy, France); 17.9 (Verdenet); 18.9, 7.1 (Verdenet); 20.1, 7.2
(J. Bortle, Stormville, NY).

     Photoelectric observations by K. Krisciunas, Mauna Kea, HI:
Sept. 22.25, V = 7.42 +/- 0.03, B-V = +0.77 +/- 0.02.


IAUC 4106-4107
     Many subscribers accidentally received two copies of one of
the above Circulars and none of the other.  A copy of each Circular
(originally issued on Friday, September 13) is therefore
contained in this mailing.  Extra copies should not be returned.


1985 October 2                 (4116)              Brian G. Marsden

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