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IAUC 3174: BRIEF X-RAY TRANSIENT; OBJECT SCHUSTER

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                                                  Circular No. 3174
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Cable Address: SATELLITES, NEWYORK     Telex: 921428
Telephone: (617) 864-5758


BRIEF X-RAY TRANSIENT
     L. J. Kaluzienski, J. L. Robinson-Saba, E. A. Boldt, S. S.
Holt, J. H. Swank, P. J. Serlemitsos and R. E. Rothschild, Goddard
Space Flight Center, report the detection of a transient x-ray
event in quick-look data from the A-2 experiment on HEAO-1.  The
source, located within an error box with corners at R.A. = 5h21m, Decl. =
-53o.6; 5h22m, -54o.2; 4h39m, -57o3; 4h36m, -56o.8 (equinox 1950.0),
is clearly present in the four high-energy (1-60 keV) detectors
(soft x-ray detectors off) during a scan of this region on ~ Feb.
9d20h24m UT.  The lower limit to the flux (2-20 keV) is S0 = 0.14
Crab, with no major variations (1s.28 integrations) evident over the
1-min scan duration.  Concurrent observations of this region with
the Ariel 5 all-sky monitor yield an upper limit of ~ 1.0 Crab
(1.5-hr average) in the 3-6 keV band.  The source is not visible (S <~
0.05 S0) in A-2 scans occurring on ~ Feb. 9d01h24m and 11d02h12m UT.
Preliminary wide-band spectral color ratios indicate a spectrum
similar in hardness to that of the Crab Nebula with no significant
low-energy (E <~ 3 keV) absorption.  The present limit on the duration
of the event (2 days >~ t >~ 1 min) is intermediate between that of
the x-ray bursters and the 'weak, high-latitude' transients.


OBJECT SCHUSTER
     H.-E. Schuster, European Southern Observatory, reports the
following semiaccurate and approximate positions of a fast-moving
asteroidal object discovered with the 100-cm Schmidt telescope.
Computations by the undersigned suggest it is of Apollo type.

     1978 UT             R. A. (1950) Decl.        Mag.
     Feb.  8.2152     10 29 12.4    -27 59 07      17
           8.2777     10 29 09.4    -27 56 48
           9.23263    10 28 48.7    -27 22 57
           9.29513    10 28 45.6    -27 20 39
          10.19167    10 28 23.4    -26 45 18
          10.25417    10 28 20.9    -26 42 46
          11.15694    10 27 58.8    -26 04 42
          12.14653    10 27 24.4    -25 18 38
          13.28611    10 26 44.7    -24 20 35
          14.28125    10 26.1       -23 25.5
          15.20521    10 25.5       -22 30


1978 February 17               (3174)              Brian G. Marsden

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