2019A&A...628A..98B

Context. This paper relates to low-mass star formation in globules, and the interaction of newly-formed stars with their environment. We follow up on the results of our earlier observations of this globule.
Aims. Our aim is to study the gas- and dust environment of the young stellar object (YSO) in globule CB88 230, the large-scale molecular outflow triggered by the jet driven by the YSO, and their interaction.
Methods. We carried out submillimetre continuum and multi-line molecular observations with several single-dish facilities, mapping the core of the globule and the large-scale outflow associated with the YSO. Results. Dust continuum and molecular line maps (of ¹²CO, C¹⁸O, CS, CH₃OH) show a flattened (axes ratio 1.5-1.7), asymmetric core with a full width at half maximum (FWHM)-diameter of 0.16-0.21pc. Line profiles of ¹²CO, ¹³CO(2-1, 3-2), and CS(2-1) show self-absorption near the YSO; the absorption dip is at a slightly (∼0.3km/s) redder velocity than that of the quiescent gas, possibly indicating infall of cooler envelope gas. The mass of the core, determined from C¹⁸O(1-0) observations, is about 8M_☉, while the virial mass is in the range 5-8M_☉, depending on the assumed density distribution. We detect a slight velocity gradient (∼0.98km/s/pc), though rotational energy is negligible with respect to gravitational and turbulent energy of the core. A fit to the spectral energy distribution of the core gives a dust temperature T_d~=18K and a gas mass of ca. 2M_☉ (assuming a gas-to-dust ratio of 100). More careful modelling of the sub-mm emission (not dominated by the relatively hot central regions) yields M~=8M_☉. From the molecular line observations we derive gas temperatures of 10-20K. A Bayesian analysis of the emission of selected molecules observed towards the YSO, yields T_kin~=21.4K (68% credibility interval 14.5-35.5K) and volume density n(H₂)~=4.6x10⁵cm^–3 (8.3x10⁴-9.1x10⁵cm^–3). We have mapped the well-collimated large-scale outflow in ¹²CO(3-2). The outflow has a dynamical age of a few 10⁴yr, and contains little mass (a few 10^–2M_☉). A misalignment between the axis of this large-scale outflow and that of the hot jet close to the YSO indicates that the outflow direction may be changing with time.