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IAUC 5959: GRS 1915+105; GRO J1008-57; 1994D

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                                                  Circular No. 5959
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Telephone 617-495-7244/7440/7444 (for emergency use only)
TWX 710-320-6842 ASTROGRAM CAM     EASYLINK 62794505
MARSDEN@CFA or GREEN@CFA (.SPAN, .BITNET or .HARVARD.EDU)


GRS 1915+105
     S. Sazonov, R. Sunyaev, and I. Lapshov, on behalf of the Granat
WATCH team, report:  "The x-ray transient GRS 1915+105, discovered
by the WATCH instrument on 1992 Aug. 15 (IAUC 5590), appeared bright
in recent WATCH observations:  the fluxes in the band 8-20 keV for
Mar. 14, 18, 21, 24, and 27 were 380 +/- 60, 400 +/- 90, 220 +/- 40,
330 +/- 80, and 180 +/- 30 mCrab, respectively.  The previous WATCH
detection of GRS 1915+105 in its high state occured at the end of
May 1993."


GRO J1008-57
     M. H. Finger, R. B. Wilson, M. Scott, M. Stollberg, and T. A.
Prince report for for the Compton Gamma Ray Observatory (CGRO) BATSE
pulsar team:  "Pulsed hard x-ray flux in the energy range 20-100 keV
is currently being detected from the source GRO J1008-57.  This
source was discovered by CGRO in an outburst in 1993 July (IAUC
5836, 5838) and subsequently observed by ASCA (IAUC 5851) and ROSAT
(IAUC 5877).  In the current outburst, pulsed flux was first
detected on 1994 Mar. 23.  The barycentric pulse period of 93.5410
+/- 0.0014 s was determined for Mar. 27.0.  The pulse profile
consists of a single broad peak, as was previously observed by
BATSE.  The spectrum of the phase-averaged pulsed flux on Mar. 26
is fit between 20 and 100 keV by an optically-thin thermal
bremsstrahlung model of the form A/E exp(-E/kT), with a flux at 45
keV of (1.0 +/- 0.2) x 10E-4 photon cmE-2 sE-1, and kT = 17.9 +/-
4.3 keV.  This is about 40 mCrab (total) in the band 20-50 keV.  If
the interval between this outburst and the last (260 days) is near
the orbital period, then a time-of-arrival analysis of the previous
outburst requires a projected semi-major axis of 600-800 light
seconds, and a mass function of 3-8 solar masses, indicating a
high-mass companion."


SUPERNOVA 1994D IN NGC 4526
     Visual magnitude estimates (cf. IAUC 5953):  Mar. 18.023 UT,
11.9 (B. H. Granslo, Fjellhamar, Norway); 19.02, 11.8 (B. H.
Granslo, Fjellhamar, Norway); 19.957, 12.0 (G. M. Hurst, Basingstoke,
England); 22.01, 11.8 (Granslo); 25.657, 11.6 (S. Takahashi, Shiga,
Japan); 27.032, 11.8 (Granslo); 28.014, 11.9 (H. Dahle, Oslo, Norway).


1994 March 29                  (5959)            Daniel W. E. Green

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