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The molecular environment of the young cluster of Class 0 young stellar objects (YSOs) located in the globule CB34 has been investigated through a multiline millimetre survey. The CO, 1 3 CO, C 1 8 O and CS emissions showthat the present star-forming process is concentrated into three molecular clumps with the size of ∼0.25 pc, which are embedded in a cool more extended gas. The spatial distribution of the high-velocity emission reveals the occurrence of multiple outflows which are associated with the brightest YSOs. The interaction of the outflows with the molecular clumps has been studied by using the abundances of products of shocked chemistry such as SiO and SO. The abundances of these molecules at the high velocities of the outflows can be used to further specify, with respect to the continuum results, the characteristics of the Class 0 YSOs. In particular, one of the YSOs which does not show the presence of SiO and SO at high velocities is thought to be in a more evolved phase where most of the molecules produced at high velocities in the shocked regions have been already destroyed.

The globule CB 34, which harbours a cluster of class 0 young stellar object (YSO) protostars, has been investigated through a multiline SO and SiO survey at millimetre wavelengths. The SO data reveal that the globule consists of three quiescent high-density (∼105 cm−3) clumps, labelled A, B and C, with sizes of ∼0.2–0.3 pc. The SiO data provide evidence for high-velocity gas across the globule. Most likely, the high-velocity gas is distributed in three distinct high-velocity outflows associated with the YSOs in each of the three clumps. High-velocity SO features have been detected only towards the two brightest SiO outflows. These broad SO components exhibit spatial and spectral distributions which are consistent with those of the SiO emission, so they can also be used as tracers of the outflows. The comparison between the spatial and spectral properties of the SO and SiO emissions in the three clumps suggests different evolutionary stages for the embedded YSOs. In particular, the YSO associated with clump C exhibits some peculiarities, namely smaller SiO linewidths, lower SiO column densities, a lack of extended SiO structure and of SO wings, and the presence of a SO spatial distribution which is displaced with respect to the location of the YSO. This behaviour is well explained if the SiO and SO molecules which were produced at high velocities in the shocked region have been destroyed or slowed down because of the interaction with the ambient medium, and the chemistry is dominated again by low-temperature reactions. Thus our observations strongly suggest that the YSO in clump C is in a more evolved phase than the other members of the cluster.

The detection of a new water maser source on the 6 16 → 5 23 transition in the Bok globule LBN 594 is presented. Besides the main feature, a number of velocity components were detected. Spectra taken within a few days interval suggest possible maser variability. Maser emission was also confirmed for two Ae/Be Herbig stars. Upper limits (3σ) are given for the 79 observed globules and 12 Herbig stars