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IAUC 6103: 1994ad; GRO J0422+32

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                                                  Circular No. 6103
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
Phone 617-495-7244/7440/7444     TWX 710-320-6842 ASTROGRAM CAM

SUPERNOVA 1994ad IN ESO 152-G26
     R. H. McNaught, Anglo-Australian Observatory, reports his
discovery of an apparent supernova (mag about 18) in ESO 152-G26 on
an I plate taken on Nov. 10 by M. Hartley with the U.K. Schmidt
telescope.  Confirmation was obtained on Nov. 11 via a CCD image
taken by D. I. Steel and G. J. Garradd with the 1.0-m reflector at
Siding Spring Observatory.  Coordinates for the supernova were
measured by McNaught from the CCD image:  R.A. = 1h47m39s.57, Decl.
= -56o17'30".0 (equinox 1950.0, uncertainty in each coordinate
0".4); SN 1994ad is situated in a spiral arm and offset 0".6 west
and 33".9 north from the galaxy's center.  No image appears in this
position on the SERC J or the European Southern Observatory B and R
surveys.  A nearby star (about 0.5 mag fainter than the supernova)
has position end figures 42s.55, 18'14".8.

GRO J0422+32
     J. Orosz and C. Bailyn, Department of Astronomy, Yale
University, report:  "Optical observations of the black-hole
candidate GRO J0422+32 in quiescence confirm an orbital period of
5.06 hr and strongly suggest a velocity semi-amplitude for the
secondary star near 400 km/s.  This would imply a mass function for
the primary star of about 1.4 solar masses.  Photometry with the
Kitt Peak 2.1-m telescope (+ Tek CCD) on Oct. 27-28 confirms  the
quiescent magnitudes reported on IAUC 6072 and reveals a double-
humped ellipsoidal lightcurve with an amplitude of 0.1 mag in I and
a period of 0.2107 +/- 0.0012 day.  Spectra obtained with the Kitt
Peak 4-m reflector (+ RC spectrograph) on Nov. 5-7 show double-
peaked H-alpha and H-beta emission lines superposed on a continuum
displaying the broad TiO absorption bands typical of early-M-type
stars.  Profile fitting to the emission lines implies an outer-disk
velocity of 460 +/- 20 km/s; in previous x-ray novae, this value
has proved to be 10-20 percent greater than the velocity
semiamplitude of the secondary.  While velocity determinations could
not be obtained for individual spectra, sums of twenty-nine 1800-s
exposures (with velocity shifts determined from sinusoids with the
period given above, zero phase at Nov. 5.0025 UT, and
semiamplitudes between 370 and 430 km/s) provided strong cross-
correlations with a template star of spectral type M0 V."

1994 November 11               (6103)            Daniel W. E. Green

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