Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

Optical Spectroscopy of V4334 Sgr: 19962000 C.S. Jeffery (csj@star.arm.ac.uk)

Summary: Optical Spectroscopy of V4334 Sgr: 1996­2000
C.S. Jeffery (csj@star.arm.ac.uk)
Armagh Observatory
D. Pollacco (d.pollacco@qub.ac.uk)
Queens University Belfast
The evolution of V4334 Sgr, or Sakurai's object, from its discov­
ery as an early F supergiant in 1996 to its fading as a late K­type
supergiant during 1999 was, in terms of normal stellar behaviour, un­
precedented. That evolution was primarily manifest through gross pho­
tometric changes (Nakano et al., 1996). It was quickly suggested that
V4334Sgr is a rare example of a hot evolved low­mass star, possibly a
white dwarf, in which nuclear reactions in the helium shell have been
reignited, causing the star to expand to giant dimensions (Benetti et
al., 1996b).
From discovery onwards, substantial changes in the optical spectrum
have been apparent. This paper reviews these changes, drawing on pub­
lished and unpublished material. It sets out the measurements neces­
sary for understanding the evolution of the star, and attempts to assess
the quantitative deductions made from the spectroscopic observations.
In the course of other observational work, both authors have ac­


Source: Armagh Observatory
Jeffery, Simon - Armagh Observatory


Collections: Physics