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Fifteen small, apparently starless Bok globules were mapped at high spatial and spectral (0.007 km s−1 channel−1) resolution in the (J=1→0) rotational line of 13CO using the 14 m radio telescope of the Five College Radio Astronomy Observatory, and the fifteen-element 3 mm array receiver QUARRY. From 120 to 360 positions per globule, sampled with half-beam spacing, were observed in the 13CO line. Gaussian fitting of the emission lines was used to establish mean radial velocities and uncertainties. Each globule radial velocity distribution on the sky was fit to a plane (solid body rotation) to yield mean velocity gradients with position, and rotation axis directions. The globules are rotating at rates about 30 times faster than velocity shifts attributable to local differential Galactic rotation. For globule assumed mean distances of 600 pc, the gradients range in a distinctly bimodal distribution, from 0.089 km s−1 pc−1 (ω∼3×10−15 s−1) to 0.950 km s−1 pc−1 (ω∼3×10−14 s−1). Detailed examination of the globu...

We have studied a sample of seven dark clouds (Bok globules) and eight Hergib Ae/Be stars in the J=1 → 0 transition of HCO+, H13CO+, HCN, and H13CN. The most abundant isotopomers were found in almost all the sources (detection rate 70–90%).From the derived physical parameters and column densities it seems that a quite similar scenario applies for the dark clouds and the gas around the Herbig stars. These similarities, together with the already known features from literature, suggest that the presently studied globules are likely to be sites of low‐mass star formation.

We have modeled chemical abundances and line profiles in the Bok globule B335. The chemical characteristics of this star‐forming core are largely determined by gas‐grain interaction in the inflowing material. As with L1498, we aim to identify the molecular species which have broad velocity distributions. The resulting line profile broadening for these species can be used to directly diagnose the characteristics of star‐formation. By comparing high resolution observational data with our model it should be possible to determine the evolutionary status of B335 and to establish the role that surface chemistry plays in protostellar clouds.