Molecular outflows, gas density distribution, and the effects of star formation in the dark cloud Barnard 5

High-velocity molecular outflows associated with three and possibly four of the IRAS sources have been detected in B5. (C-18)O mapping indicates that the cloud contains at least five dense fragments, but only IRS 1 appears to be located at a molecular column density maximum. From the time scales of the outflows, it is concluded that star formation has been taking place over an extended period of approximately a few x 10 to the 5th yr. 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. It is suggested that the material is recycled between clump and interclump regions, reducing the rate of star formation, and inhibiting the attainment of a steady state chemistry.