Central Bureau for Astronomical Telegrams
IAUC 7747: SS 433; 1RXS J232953.9+062814
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Circular No. 7747
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SS 433
T. Kotani, Goddard Space Flight Center; and S. Trushkin,
Laboratory of Radio-Astronomical Observations, Special
Astrophysical Observatory, write: "The RATAN-600 Radio Telescope
(flux density limit 0.5 mJy; absolute brightness temperature limit
0.05 mK) in the North Caucasus, Russia, has observed a flare in the
microquasar SS433 on Nov. 2. Flux densities reached 1.3 Jy at 2.3
GHz on Nov. 3.6 UT. The flare indicates that the source entered
its high state, and successive flares exceeding 1 Jy with intervals
of 8-23 days are expected. The probability of the occurrence of a
second flare within 23 days is estimated to be 90 percent, based on
the archival radio data. The source will be monitored in the radio
band until Dec. 31, and PCA/RXTE monitoring observations will begin
on Nov. 9.3. If SS433 experiences a flare during this period, it
will be the first flare from the source observed in a
multi-wavelength campaign. We strongly encourage spectroscopic and
photometric monitoring observations."
1RXS J232953.9+062814
M. Uemura, R. Ishioka, and T. Kato, Kyoto University; P.
Schmeer, Bischmisheim, Germany; H. Yamaoka, Kyushu University; D.
Starkey, Auburn, IN; T. Vanmunster, Landen, Belgium; and J. Pietz,
Erftstadt, Germany, on behalf of the VSNET collaboration team,
write: "On Nov. 3.926 UT, P. Schmeer detected an outburst (at m_v =
12.5) of this object, classified as a dwarf nova by Jingyao et al.
(1998, Ann. Shanghai Obs. 19, 235). Our CCD photometry (bandpass
close to Cousins R) on Nov. 4.47-6.17 revealed superhumps with
amplitudes of 0.2-0.3 mag and a period of 0.046311(12) day,
indicating that this object is an SU UMa-type dwarf nova. This
short superhump period means that the orbital period of this object
is certainly below the 'period minimum' of hydrogen-rich
cataclysmic variables (about 1.3 hr). According to Jingyao et al.,
the quiescent spectrum was dominated by Balmer emission lines,
which indicates that this object is not an AM CVn star but a
hydrogen-rich system. Except for this object, we know only one
source (V485 Cen) in this class (IAUC 6666). Comparing our CCD
images with Digital Sky Survey images, this object shows noticeable
proper motion (up to 0".1/yr). Its relative brightness and large
proper motion indicate a small distance for this object, which is
thus one of the most important systems to study the evolutionary
scenario of cataclysmic variables. Follow-up observations are
strongly encouraged."
(C) Copyright 2001 CBAT
2001 November 6 (7747) Daniel W. E. Green
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