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We present the results of an interferometric study of the N2H+(1--0) emissionfrom nine nearby, isolated, low-mass protostellar cores, using the OVROmillimeter array. The main goal of this study is the kinematic characterizationof the cores in terms of rotation, turbulence, and fragmentation. Eight of thenine objects have compact N2H+ cores with FWHM radii of 1200 -- 3500 AU,spatially coinciding with the thermal dust continuum emission. The only moreevolved (Class I) object in the sample (CB 188) shows only faint and extendedN2H+ emission. The mean N2H+ line width was found to be 0.37 km/s. Estimatedvirial masses range from 0.3 to 1.2 M_sun. We find that thermal and turbulentenergy support are about equally important in these cores, while rotationalsupport is negligible. The measured velocity gradients across the cores rangefrom 6 to 24 km/s/pc. Assuming these gradients are produced by bulk rotation,we find that the specific angular momenta of the observed Class 0 protostellarcores are intermediate between those of dense (prestellar) molecular cloudcores and the orbital angular momenta of wide PMS binary systems. There appearsto be no evolution (decrease) of angular momentum from the smallest prestellarcores via protostellar cores to wide PMS binary systems. In the context thatmost protostellar cores are assumed to fragment and form binary stars, thismeans that most of the angular momentum contained in the collapse region istransformed into orbital angular momentum of the resulting stellar binarysystems.

OVRO N2H+ Observations of Class 0 Protostars: Constraints on the Formation of Binary Stars