Electronic Telegram No. 1597
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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CBAT@CFA.HARVARD.EDU (science)
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LV VELORUM
     H. E. Bond, Space Telescope Science Institute, reports that LV Vel --
the hydrogen-deficient central star of the planetary nebula "Longmore 4"
(Longmore 1977, MNRAS 178, 251; R.A. = 10h05m45s.7, Decl. = -44o21'32",
equinox 2000.0), whose low-amplitude pulsations were discovered by Bonds
and Meakes (1990, A.J. 100, 783) -- normally has a PG-1159-type absorption
spectrum, with the O VI 381.1-383.4-nm doublet in emission.  On three past
occasions (one in 1992, two in 2006; Bond 2008, ASP Conf. Series 391, 129),
the spectrum has changed temporarily to an emission-line [WCE] type, with
strong emission at the C IV + He II complex near 465.9-468.6 nm and of O VI
529.1-nm.  A spectrum obtained on 2008 Nov. 30.27 UT with the SMARTS 1.5-m
telescope at Cerro Tololo by M. Hernandez and F. Walter shows that a new
emission-line outburst is underway.  Spectroscopic and photometric
monitoring, including high-speed photometry of the star's GW Vir-type
pulsations, is desirable throughout the duration of the current event.
The previous spectroscopic outbursts of LV Vel (Lo 4) lasted no more than
(an upper limit of) about 2 weeks.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2008 CBAT
2008 December 2                  (CBET 1597)              Daniel W. E. Green