CO emission in optically obscured (type-2) quasars at redshifts
  z=0.1-0.4
  We present a search for CO emission in a sample of ten type-2 quasar host
galaxies with redshifts of z=0.1-0.4. We detect CO(J=1-0) line emission with
>=5sigma in the velocity integrated intensity maps of five sources. A sixth
source shows a tentative detection at the ~4.5sigma level of its CO(J=1-0) line
emission. The CO emission of all six sources is spatially coincident with the
position at optical, infrared or radio wavelengths. The spectroscopic redshifts
derived from the CO(J=1-0) line are very close to the photometric ones for all
five detections except for the tentative detection for which we find a much
larger discrepancy. We derive gas masses of ~(2-16)x10^9Msun for the CO
emission in the six detected sources, while we constrain the gas masses to
upper limits of Mgas<=8x10^9Msun for the four non-detections. These values are
of the order or slightly lower than those derived for type-1 quasars. The line
profiles of the CO(J=1-0) emission are rather narrow (<=300km/s) and single
peaked, unveiling no typical signatures for current or recent merger activity,
and are comparable to that of type-1 quasars. However, at least one of the
observed sources shows a tidal-tail like emission in the optical that is
indicative for an on-going or past merging event.
  We also address the problem of detecting spurious ~5sigma emission peaks
within the field of view.
