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Related papers: Accretion--ejection phenomena from young stars

200 papers

Accretion dynamics in the forming of young stars is still object of debate because of limitations in observations and modelling. Through scaled laboratory experiments of collimated plasma accretion onto a solid in the presence of a magnetic…

Newly formed stars are often observed to possess circumstellar disks, from which mass continues to be accreted onto the star and fed into outflowing jets, and which eventually may evolve into dusty debris disks and planetary systems. Recent…

Astrophysics · Physics 2007-05-23 A. Konigl

We present the results of 2.5-dimensional resistive magnetohydrodynamic (MHD) simulations of the magnetic interaction between a weakly magnetized neutron star and its accretion disk. General relativistic effects are simulated by using the…

Astrophysics · Physics 2009-11-10 Yoshiaki Kato , Mitsuru Hayashi , Ryoji Matsumoto

Young stars and planetary systems form in molecular clouds. For classical T Tauri stars (CTTS, F-K type precursors) the accretion disk does not reach down to the central star, but it is truncated near the co-rotation radius. The inner edge…

Solar and Stellar Astrophysics · Physics 2015-06-11 Hans Moritz Günther

Classical T Tauri stars are low mass young forming stars that are surrounded by a circumstellar accretion disc from which they gain mass. Despite this accretion and their own contraction that should both lead to their spin up, these stars…

Solar and Stellar Astrophysics · Physics 2013-10-17 Jonathan Ferreira

Strong magnetic fields play a crucial role in the removal of angular momentum from collapsing clouds and protostellar discs and are necessary for the formation of disc winds as well as jets from the inner disc and indeed, strong large-scale…

Solar and Stellar Astrophysics · Physics 2015-06-03 Jonathan Braithwaite

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…

Astrophysics of Galaxies · Physics 2017-11-02 Masahiro N. Machida

It was proposed earlier that the relativistic ejections observed in microquasars could be produced by violent magnetic reconnection episodes at the inner disk coronal region. Here we revisit this model, which employs a standard accretion…

High Energy Astrophysical Phenomena · Physics 2015-05-19 E. M. de Gouveia Dal Pino , P. P. Piovezan , L. H. S. Kadowaki

Forming massive stars launch outflows of magnetic origin, which in fact serve as a marker for finding sites of massive star formation. However, both the theoretical and observational study of the mechanisms that intervene in the formation…

Solar and Stellar Astrophysics · Physics 2023-01-18 André Oliva , Rolf Kuiper

We investigate the evolution of a disk wind into a collimated jet under the influence of magnetic diffusivity, assuming that the turbulent pattern in the disk will also enter the disk corona and the jet. Using the ZEUS-3D code in the…

Astrophysics · Physics 2009-11-07 Christian Fendt , Miljenko Cemeljic

The formation of astrophysical objects of different nature and size, from black holes to gaseous giant planets, involves a disk-jet system, where the disk drives the mass accretion onto a central compact object and the jet is a fast…

Solar and Stellar Astrophysics · Physics 2022-09-02 Luca Moscadelli , Alberto Sanna , Henrik Beuther , André Oliva , Rolf Kuiper

Accretion supermassive black holes in the center of active galaxies usually produce ``jets''-collimated bipolar outflows of relativistic particles. Magnetic fields near the black hole event horizon may play a crucial role in the formation…

High Energy Astrophysical Phenomena · Physics 2025-03-05 Yongyun Chen , Qiusheng Gu , Junhui Fan , Xiaotong Guo , Xiaoling Yu , Nan Ding , Dingrong Xiong

Magnetic fields are fundamental to the dynamics of both accretion disks and the jets that they often drive. We review the basic physics of these phenomena, the past and current efforts to model them numerically with an emphasis on the…

High Energy Astrophysical Phenomena · Physics 2015-08-19 John F. Hawley , Christian Fendt , Martin Hardcastle , Elena Nokhrina , Alexander Tchekhovskoy

Rotation period measurements of low-mass stars show that the spin distributions in young clusters do not exhibit the spin-up expected due to contraction, during the phase when a large fraction of stars are still surrounded by accretion…

Solar and Stellar Astrophysics · Physics 2023-03-24 Amard L. , Matt S. P

The relation between the mass accretion rate onto the circumstellar disc and the rate of mass ejection by magnetically driven winds is investigated using three-dimensional magnetohydrodynamics simulations. Using a spherical cloud core with…

Solar and Stellar Astrophysics · Physics 2017-07-05 Yuko Matsushita , Masahiro N. Machida , Yuya Sakurai , Takashi Hosokawa

We present simulations of collapsing 100 M_\sun mass cores in the context of massive star formation. The effect of variable initial rotational and magnetic energies on the formation of massive stars is studied in detail. We focus on…

Solar and Stellar Astrophysics · Physics 2015-05-28 D. Seifried , R. Banerjee , R. S. Klessen , D. Duffin , R. E. Pudritz

We have constructed the foundations to a series of theoretical diagnostic methods to probe the jet phenomenon in young stars as observed at various optical forbidden lines. We calculate and model in a self-consistent manner the physical and…

Astrophysics · Physics 2015-06-24 Hsien Shang

We review advances in the theoretical and computational studies of disk winds, jets and outflows including: the connection between accretion and jets, the launch of jets from magnetized disks, the coupled evolution of jets and disks, the…

Astrophysics · Physics 2007-05-23 Ralph E. Pudritz , Rachid Ouyed , Christian Fendt , Axel Brandenburg

We perform a series of two-dimensional magnetohydrodynamic core-collapse simulations of rapidly rotating and strongly magnetized massive stars. To study the properties of magnetic explosions for a longer time stretch of postbounce…

Astrophysics · Physics 2009-06-23 Tomoya Takiwaki , Kei Kotake , Katsuhiko Sato

The propeller regime of disk accretion to a rapidly rotating magnetized star is investigated here for the first time by axisymmetric 2.5D magnetohydrodynamic simulations. An expanded, closed magnetosphere forms in which the magnetic field…