Radial velocity monitoring of long period hot subdwarf + main sequence   binaries with HERMES@Mercator
  Population synthesis models predict that the majority of sdBs form through stable mass transfer leading to long period binaries. To date, about a hundred close short-period binaries with an sdB component have been found, but not a single long-period system has been established. We show preliminary results from our recent effort in determining orbits for a sample of long-period sdB systems using the HERMES spectrograph on the Mercator telescope. 
Roy H. {\O}stensen and Hans Van Winckel
astro-ph.SR