Title: A one-sided knot ejection at the core of the HH 111 outflow Authors: L. Gomez (1,2), L. F. Rodriguez (3), L. Loinard (1,3) ((1) MPIfR, (2) Universidad de Chile, (3) CRyA-UNAM)
We present an astrometry study of the radio source VLA 1 at the core of the HH 111 outflow using new data (2007) as well as archival observations (1992-1996). All data were taken at 3.6 cm with the Very Large Array in its most extended (A) configuration. The source VLA 1 has undergone a dramatic morphological change, showing a one-sided knot ejection in the 2007 epoch. We also report on the detection of a 3.6 cm compact continuum source (VLA 3) located at (-10.6",98.7") from VLA 1. No significant absolute proper motions were found for VLA 1 and VLA 3 and the upper limits are consistent with those found for (embedded) radio sources in the Orion Nebula. We favour the interpretation that in the continuum at 3.6 cm we are observing two nearly perpendicular jets. HH 111 presents a new case of one-sided jet ejection in a young stellar object. The Galactic (or extragalactic) nature of VLA 3 remains unclear.
Title: High Angular Resolution Observations at 7-mm of the Core of the Quadrupolar HH 111/121 Outflow Authors: L. F. Rodriguez, J. M. Torrelles, G. Anglada, B. Reipurth
We present sensitive, high angular resolution (0 lap.{''}05) VLA continuum observations made at 7 mm of the core of the HH 111/121 quadrupolar outflow. We estimate that at this wavelength the continuum emission is dominated by dust, although a significant free-free contribution (~30%) is still present. The observed structure is formed by two overlapping, elongated sources approximately perpendicular to each other as viewed from Earth. We interpret this structure as either tracing two circumstellar disks that exist around each of the protostars of the close binary source at the core of this quadrupolar outflow or a disk and a jet perpendicular to it. Both interpretations have advantages and disadvantages, and future high angular resolution spectroscopic millimetre observations are required to favour one of them in a more conclusive way.