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IAUC 5859: 1993W; GX 1+4

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                                                  Circular No. 5859
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)


SUPERNOVA 1993W IN ANONYMOUS GALAXY
     E. Cappellaro, European Southern Observatory, communicates:
"On Aug. 20.4 UT, I obtained a low-resolution spectrogram (range
360-700 nm, resolution 2 nm) of SN 1993W (cf. IAUC 5848) using the
3.6-m ESO telescope (+ EFOSC).  The spectrum shows broad Balmer
lines with a P-Cyg profile overimposed on a blue continuum.
Absorption minima are measured at 429.7, 479.7, and 647.4 nm.  The
supernova is therefore of type II near maximum light.  Provisional
photometry gives B = 18.3."
     A. V. Filippenko and T. Matheson, University of California at
Berkeley, report:  "CCD spectrograms (range 310-1000 nm) obtained
on Sept. 10 UT with the Shane 3-m reflector at Lick Observatory
reveal that SN 1993W is of type II, within a few weeks of maximum
brightness.  The hydrogen Balmer lines, especially H-alpha, have
prominent P-Cyg profiles.  Narrow H-alpha emission from a faint
underlying H II region and from the galaxy nucleus appears at 668 nm
(z = 0.018).  It should be possible to determine an accurate distance
using the Expanding Photosphere Method, given enough
observations."


GX 1+4
     M. H. Finger, Computer Sciences Corporation; R. B. Wilson and
G. J. Fishman, Marshall Space Flight Center, NASA; and L. Bildsten,
D. Chakrabarty, and T. A. Prince, California Institute of Technology,
report for the Compton Gamma Ray Observatory BATSE team:  "
Beginning Aug. 27, the x-ray binary pulsar GX 1+4 has dramatically
brightened in the hard (> 20 keV) x-ray band.  The pulsed flux is
now the highest seen by BATSE in more then two years of monitoring.
On Sept. 5, the barycentric pulse period was 120.567 +/- 0.005 s,
and the phase averaged pulsed flux (20-120 keV) is well fit with
F(E) = (A/E)exp(-E/kT), where kT = 27 +/- 3 and F(50 keV) = (2.1
+/- 0.1) x 10E-4 photon cmE-2 sE-1 keVE-1.  The period derivative
has increased steadily from 1.2 +/- 0.4 s/yr as measured in 1993
March to the current rate of 3.7 +/- 0.3 s/yr.  The cause of the GX
1+4 outbursts is not known, but may be due to variations in the M6
III red giant companion V2116 Oph (V = 19, R = 15, k = 8; finder
chart in Doxsey et al. 1977, Nature 270, 586)."


1993 September 10              (5859)            Daniel W. E. Green

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