The hidden past of Sakurai's object - Stellar properties before the final helium flash

Authors
Kerber, F Koppen, J Roth, M Trager, SC
Citation
F. Kerber et al., The hidden past of Sakurai's object - Stellar properties before the final helium flash, ASTRON ASTR, 344(3), 1999, pp. L79-L82
Citations number
30
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY AND ASTROPHYSICS
ISSN journal
00046361 → ACNP
Volume
344
Issue
3
Year of publication
1999
Pages
L79 - L82
Database
ISI
SICI code
0004-6361(199904)344:3<L79:THPOSO>2.0.ZU;2-7
Abstract
We derive the properties of Sakurai's object before its sudden evolutionary change by studying the remnant ionization of the old planetary nebula (PN) surrounding it. The star must have had a surface temperature of 98 000 +/- 7000 K (95 000 +/- 7000 K). For a distance of 1.5 kpc (5.5 kpc) the lumino sity should have been 25 +/- 5 L. (240 +/- 40 L.). The central star thus wa s highly evolved and had already reached the tip of the white dwarf cooling track. Sakurai's object indeed is an example of a star undergoing a very l ate helium flash.