CO Observations of a High Velocity Cloud

We report a null detection of 12CO emission from a sub-condensation in a High Velocity Cloud (HVC). As a consequence of this, an upper limit of n(H2)x(CO)/(DV/DR)<=2*10E-5 was set. This implies that 12CO abundance is deficient by at least a factor of 10 if the HVC is predominantly molecular, otherwise the CO abundance of the HVC might be normal.