Molecular outflows, gas density distribution, and the effects of star formation in the Dark Cloud Barnard 5.

We have detected high velocity molecular outflows associated with the four IRAS sources in B5. We present well sampled C (18)O maps which indicate that the cloud contains at least five dense fragments. Only IRS'1 appears to be located at a molecular column density maximum. From the timescales of the outflows, we conclude that star formation has been taking place over an extended period of ~'few'x'10(5)'yr, and that the mechanical energy input to the cloud from the outflows associated with young stellar objects certainly influences, and may be sufficient to stabilize, or even to disrupt, the fragments in which the stars formed. We suggest that material is recycled between clump and interclump regions, reducing the rate of star formation, and inhibiting the attainment of a steady state chemistry.