SIMBAD references

We present a formulation of the Monte Carlo method which should be capable of treating radiative transfer problems even at very high optical depths (τ≫10⁴) and apply this tool to predict rotational H₂O line spectra for the protostellar object B335 for future observational tests with space borne facilities. The physical model of the source is based on published observations in lines of CS, for which we obtain model results which are in agreement with previous computations. We apply our model also to line profiles of CO isotopomers observed at high spatial resolution and derive the total CO cooling rate for B335. From the comparison with the derived H₂O cooling rates, we are led to conclude, quite generally, that H₂O is probably not the major coolant of low-mass protostellar collapse.