S. Geier, V. Schaffenroth, H. Hirsch, A. Tillich, U. Heber, L. Classen, T. Kupfer, P. F. L. Maxted, R. H. Oestensen, B. N. Barlow, S. J. O'Toole, T. R. Marsh, B. T. Gaensicke, O. Cordes, R. Napiwotzki
The project Massive Unseen Companions to Hot Faint Underluminous Stars from
SDSS (MUCHFUSS) aims at finding hot subdwarf stars with massive compact
companions (massive white dwarfs M>1.0 Msun, neutron stars or stellar mass
black holes). The existence of such systems is predicted by binary evolution
theory and some candidate systems have been found. We classified about 1400 hot
subdwarf stars from the Sloan Digital Sky Survey (SDSS) by colour selection and
visual inspection of their spectra. Stars with high velocities have been
reobserved and individual SDSS spectra have been analysed. In total 201 radial
velocity variable subdwarfs have been discovered and about 140 of them have
been selected as good candidates for follow-up time resolved spectroscopy to
derive their orbital parameters and photometric follow-up to search for
features like eclipses in the light curves. Up to now we found seven close
binary sdBs with short orbital periods ranging from 0.21 d to 1.5 d and two
eclipsing binaries with companions that are most likely of substellar nature. A
new pulsating sdB in a close binary system has been discovered as well.
View original:
http://arxiv.org/abs/1112.2922
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