Electronic Telegram No. 370
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://cfa-www.harvard.edu/iau/cbat.html


HD 109962
     F. Walter, Stony Brook University; H. E. Bond, Space Telescope
Science Institute; and A. Pasten, Cerro Tololo Interamerican
Observatory, report that a spectrum obtained with the SMARTS 1.5-m
telescope spectrograph of HD 109962 (= NSV 19448) on Jan. 16.2 UT
shows He II 468.6-nm emission (equivalent width -0.29 nm)
superposed on the star's F2 V spectrum.  As described by S. Otero
(http://ar.geocities.com/varsao/NSV_19448.htm), HD 109962 is an
eclipsing binary with a period of 0.89 days that additionally shows
outbursts of about 0.8 mag and duration about 40 days occurring about
once a year, according to ASAS-3 data, with the latest outburst
having begun in late December 2005.  The He II emission suggests a
transient source of ionizing radiation, perhaps a compact object in
an eccentric orbit accreting in the stellar wind.  Observations at
all wavelengths, including x-ray and ultraviolet, are strongly
encouraged.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2006 CBAT
2006 January 19                  (CBET 370)               Daniel W. E. Green