Collapse of a 1 M_⊙cloud. Radial profiles (across and down) of density (panel a), pressure (panel b), gas temperature (panel c), velocity (panel d), enclosed mass (panel e), optical depth (panel f), Mach number (panel g), mean molecular weight (panel h), and thermal structure (panel i) are shown at the snapshot after second core formation. The black line in panel i shows the temporal evolution of the central temperature and density. The initial profile is shown by the black dot-dashed line, the first collapse phase is indicated by the black dashed line, and the bluish purple line describes the structure after formation of the second hydrostatic core.