GRAVITATIONAL INFALL IN THE DENSE CORES L1527 AND L483

Lines of N2H+, C3H2, and H2CO show kinematic evidence of gravitational infall in L1527, and probably also in L483. Three trends appear to in dicate infall, rather than outflow or rotation: (a) at each protostar position, line peak and centroid velocities get bluer by 0.1-0.3 km s( -1) with increasing line optical depth; (b) in maps of C3H2 and H2CO l ines, peak and centroid velocities get bluer by a similar amount as po sitions approach each protostar; and (c) C3H2 line widths in L1527 inc rease as positions approach the protostar. Also, in both sources H2CO lines show the infall ''signature'' of spatially concentrated double-p eaked profiles, with their blue peaks brighter than their red peaks, a s seen previously in B335. Many asymmetric profiles have a single blue shifted peak with a red shoulder, or two peaks with blue/red intensity ratio greater than 3. These are hard to fit with spherical infall mod els, owing perhaps to the effects of the bipolar outflow. In each sour ce, H2CO line wings show clear evidence of collimated outflow.