Related papers: Multi-jets structure rather than rotation of the N…
The bipolar jet of the NGC 1333 IRAS 4A2 protostar shows a velocity gradient in the direction perpendicular to the jet axis. This lateral velocity gradient can be seen throughout the jet imaged in a silicon monoxide line, 2500-8700 AU from…
We compare the structures of the jets of the pre-planetary nebulae (PN) CRL618 and the young stellar object (YSO) NGC 1333 IRAS4A2 and propose that in both cases the jets are launched near periastron passages of a highly eccentric binary…
I reexamine recent observations of velocity profiles across jets blown by young stellar objects, and argue that the observations do not support the interpretation of jets rotating around their symmetry axes. Instead, I propose that the…
We have performed observations of water maser emission towards a sample of low-mass protostars, in order to investigate the properties of jets associated with the earliest stages of star formation and their interaction with the surrounding…
Owing to the paucity of sub-arcsecond (sub)mm observations required to probe the innermost regions of newly forming protostars, several fundamental questions are still being debated, such as the existence and coevality of close multiple…
Context: The earliest evolutionary stages of low-mass protostars are characterised by hot and fast jets which remove angular momentum from the circumstellar disk, thus allowing mass accretion onto the central object. However, the launch…
Observations of Young Stellar Objects (YSOs) systems reveal a wide diversity of jet properties, from well-collimated bipolar jets to uni-polar jets and systems with no detectable jet. Both prograde and counter-rotating jets are reported,…
We analyse recent high-quality Atacama Large Millimeter Array (ALMA) molecular line mapping observations of the northeast jet of the young stellar object (YSO) OMC 2/FIR6b (HOPS-60) and find that these ALMA observations are much more likely…
The NGC 1333 IRAS 4A protobinary was observed in the ammonia (2, 2) and (3, 3) lines with an angular resolution of 0.3 arcsec. The ammonia emission source of IRAS 4A2 is elongated in the direction perpendicular to the bipolar jet and has a…
A protostellar jet and outflow are calculated for \sim 270 yr following the protostar formation using a three dimensional magnetohydrodynamics simulation, in which both the protostar and its parent cloud are spatially resolved. A…
The NGC 1333 IRAS 4A protobinary was observed in the 1.3 cm and 6.9 mm continuum and the ammonia and SiO lines, with an angular resolution of about 0.4 arcseconds. The continuum maps show the circumstellar structures of the two protostars,…
We present SMA CO(2-1) observations toward the protostellar jet driven by SVS13A, a variable protostar in the NGC1333 star-forming region. The SMA CO(2-1) images show an extremely high-velocity jet composed of a series of molecular…
We investigate one of the best examples of disk+jet systems around an early B-type (proto)star, IRAS20126+4104. This object is an ideal target for resolution of its disk and the determination of its physical and kinematical structure.…
We imaged the protostars of the nearby region NGC1333 IRAS 4 in the water maser line at 22.2 GHz by using the VLBA in phase referencing at milliarcsecond scale over four epochs spaced by one month to measure proper motions. We measure the…
I argue that the Doppler shift asymmetries observed in some young stellar object (YSO) result from the interaction of the jets with the circumstellar gas, rather than from jets' rotation. The jets do rotate, but at a velocity much below…
Jets from young stars represent one of the most striking signposts of star formation. The phenomenon has been researched for over two decades and there is now general agreement that such jets are generated as a by-product of accretion; most…
We present here an extensive analysis of the protostellar jet driven by IRAS 20126+4104, deriving the kinematical, dynamical, and physical conditions of the H2 gas along the flow. The jet has been investigated by means of near-IR H2 and…
The driving mechanism of protostellar outflows and jets and their effects on the star formation process obtained from recent theoretical and numerical studies are described. Low-velocity outflows are driven by an outer region of the…
The recently discovered protostellar jet known as HH212 is beautifully symmetric, with a series of paired shock knots and bow shocks on either side of the exciting source region, IRAS 05413-0104 (Zinnecker et al. 1998). We present VLA…
The majority of stars are part of gravitationally bound stellar systems, such as binaries. Observations of protobinary systems constrain the conditions that lead to stellar multiplicity and subsequent orbital evolution. We report…