Collimated jets from the first core

We have performed smoothed particle magnetohydrodynamics (SPMHD) simulations demon- strating the production of collimated jets during collapse of 1 Mmolecular cloud cores to form the 'first hydrostatic core' in low-mass star formation. Recently, a number of candidate first-core objects have been observed, including L1448 IRS2E, L1451-mm and Per-Bolo 58, although it is not yet clear that these are first hydrostatic cores. Recent observations of Per-Bolo 58 in particular appear to show collimated, bipolar outflows which are inconsistent with pre- vious theoretical expectations. We show that low-mass first cores can indeed produce tightly collimated jets (opening angles 10 ◦ ) with speeds of ∼2-7 km s −1 , consistent with some of the observed candidates. We have also demonstrated, for the first time, that such phenomena can be successfully captured in SPMHD simulations.

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