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Related papers: Jets from young stars and brown dwarfs

200 papers

The driving mechanism of jets and outflows in star formation process is studied using resistive MHD nested grid simulations. We calculated cloud evolution from the molecular cloud core to the stellar core. In the collapsing cloud core, we…

Astrophysics · Physics 2007-05-23 Masahiro N. Machida , Shu-ichiro Inutsuka , Tomoaki Matsumoto

Though widely observed to be emanating out from a variety of galactic and extra-galactic sources, the underlying physical mechanism behind the formation of the cosmic jets and outflows are wrapped around by the veil of mystery till date.…

Astrophysics · Physics 2007-05-23 Tapas K. Das

During their birth all stars undergo periods of copious mass loss, frequently characterized by the occurrence of bipolar outflows. These outflows are believed to play a fundamental role in the star formation process. However the exact…

Astrophysics · Physics 2007-05-23 Derek E. Bretherton , Toby J. T. Moore , Naomi A. Ridge

Jets, collimated outflows of particles and fields, are observed in a wide variety of astrophysical systems, including Active Galactic Nuclei of various types, microquasars, gamma-ray bursts, and young stellar objects. Despite intensive…

High Energy Astrophysical Phenomena · Physics 2021-06-29 Gustavo E. Romero

Low-mass pre-main sequence (PMS) stars are strong X-ray sources, because they possess hot corona like their older main-sequence counterparts. Unique to young stars, however, are X-rays from accretion and outflows, and both processes are of…

Solar and Stellar Astrophysics · Physics 2023-04-05 P. Christian Schneider , H. Moritz Günther , Sabina Ustamujic

As outflow activity in low mass protostars is strongly connected to ac- cretion it is reasonable to expect accreting brown dwarfs to also be driving out- flows. In the last three years we have searched for brown dwarf outflows using high…

Solar and Stellar Astrophysics · Physics 2015-05-13 E. T. Whelan , T. P. Ray , F. Bacciotti , S. Randich , A. Natta

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…

Solar and Stellar Astrophysics · Physics 2015-06-23 Masahiro N. Machida

Powerful, highly collimated jets, surrounded by bipolar molecular outflows, are commonly observed near Young Stellar Objects (YSOs). In the usual theoretical picture of star formation, a jet is ejected from a magnetized accretion disk, with…

Astrophysics · Physics 2009-11-07 T. Lery , R. N. Henriksen , J. D. Fiege , T. P. Ray , A. Frank , F. Bacciotti

We review the current state of observational work on the formation of brown dwarfs, focusing on their initial mass function, velocity and spatial distributions at birth, multiplicity, accretion, and circumstellar disks. The available…

The loss of mass from protostars, in the form of a jet or outflow, is a necessary counterpart to protostellar mass accretion. Outflow ejection events probably vary in their velocity and/or in the rate of mass loss. Such `episodic' ejection…

Highly collimated supersonic jets and less collimated outflows are observed to emerge from a wide variety of astrophysical objects. They are seen in young stellar objects (YSOs), proto-planetary nebulae, compact objects (like galactic black…

Astrophysics · Physics 2009-11-10 Elisabete M. de Gouveia Dal Pino

Using three-dimensional magnetohydrodynamics simulations, the driving of protostellar jets is investigated in different star-forming cores with the parameters of magnetic field strength and mass accretion rate. Powerful high-velocity jets…

Astrophysics of Galaxies · Physics 2021-09-22 Masahiro N. Machida

In this work, the gas infall and the formation of outflows around low and high mass protostars are investigated. A radial self-similar approach to model the transit of the molecular gas around the central object is employed. We include…

Astrophysics · Physics 2009-11-13 C. Combet , T. Lery , G. C. Murphy

Jets and outflows produced during star-formation are observed on many scales: from the "micro-jets" extending a few hundred Astronomical Units to the "super-jets" propagating to parsecs distances. Recently, a new "class" of short-lived…

Solar and Stellar Astrophysics · Physics 2009-11-19 Andrea Ciardi

Young stars are associated with prominent outflows of molecular gas. The ejection of gas via these outflows is believed to remove angular momentum from the protostellar system, thus permitting young stars to grow by accretion of material…

Solar and Stellar Astrophysics · Physics 2016-12-16 Per Bjerkeli , Matthijs H. D. van der Wiel , Daniel Harsono , Jon P. Ramsey , Jes K. Jørgensen

The observational properties of brown dwarfs pose challenges to the theory of star formation. Because their mass is much smaller than the typical Jeans mass of interstellar clouds, brown dwarfs are most likely formed through secondary…

Astrophysics · Physics 2007-05-23 Ing-Guey Jiang , G. Laughlin , D. N. C. Lin

We review the known properties of molecular outflows from low- and high-mass young stars. General trends among outflows are identified, and the most recent studies on the morphology, kinematics, energetics, and evolution of molecular…

We conjecture that brown dwarfs are substellar objects because they have been ejected from small newborn multiple systems which have decayed in dynamical interactions. In this view, brown dwarfs are stellar embryos for which the star…

Astrophysics · Physics 2009-11-06 Bo Reipurth , Cathie Clarke

Brown dwarfs, which occupy a fuzzy gap in mass between stars and planets, appear to be common both in the solar neighborhood and in star-forming regions. Their origin is a topic of significant current interest and debate. Some astronomers…

Astrophysics · Physics 2007-05-23 Ray Jayawardhana

We have surveyed 84 Class 0, Class I, and flat-spectrum protostars in mid-infrared [Si II], [Fe II] and [S I] line emission, and 11 of these in far-infrared [O I] emission. We use the results to derive their mass outflow rates. Thereby we…