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IAUC 3320: Cir X-1; 2A 1052+606; WZ Sge

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IAUC number


                                                  Circular No. 3320
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


CIRCINUS X-1
     L. J. Kaluzienski and S. S. Holt, Goddard Space Flight Center,
report the detection of a peculiar flaring episode from Cir X-1
with the Ariel 5 all-sky monitor.  The flare commenced on Jan.
15.35 +/- 0.04 UT and is characterized by a rapid turn-on (< 100 min),
dip to the preflare flux level (~ 10 hours in duration) and subsequent
recovery.  The peak flux (3-6 keV) reached in the initial
rise was approximately twice that of the Crab Nebula, more than an
order of magnitude above the preceding quiescent level.  Following
the dip the intensity recovered to a level approximately equal to
that of the Crab, and the source was still bright when last observed
on Jan. T7.  Based upon the latest available ephemeris and
period (IAUC 3099), the observed time of the dip precedes the expected
turn-off in the 16.6-day cycle by ~ 12 hours.  This behavior
differs distinctly from that exhibited by Cir X-1 during 1975-1977
and represents the first unambiguous detection of the source with
the all-sky monitor since 1978 Feb. (IAUC 3171).


2A 1052+606
     D. Crampton, Dominion Astrophysical Observatory, communicates:
"Spectroscopic observations of SAO 015338, the proposed counterpart
for 2A 1052+606 (IAUC 3176), reveal that it is a spectroscopic
binary of the RS-CVn type with period 7.50 days, K ~ 30 km/s and
epoch of maximum positive velocity 1979 Jan. 8.1 UT.  Photometric
observations to look for correlated periodic variations would be
very valuable."


WZ SAGITTAE
     Further to the note by Guinan and McCook on IAUC 3319, D.
Targan, Physics Department, Brown University, reports that analysis
of about 100 photometric observations made by him during Dec. 10-24
gives for the time of (heliocentric) minimum light the formula 1978
Dec. 14.96298 + 0.057234 E.  The period is 47s.2 longer than the
pre-outburst value found by Robinson et al. (1978, Astrophys. J. 219,
168).  Selected V magnitudes, obtained as described on IAUC 3315
are: 1978 Dec. 13.9625 UT, 9.48; 13.9708, 9.66; 14.9549, 9.82;
14.9965, 9.55; 15.9396, 10.02; 15.9806, 9.91; 19.9313, 10.14;
19.9931, 10.23; 23.9431, 10.62; 23.9729, 10.69; 24.0000, 10.11.


1979 January 22                (3320)              Brian G. Marsden

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