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Related papers: On the Zeeman Effect in Magnetically-Arrested Disk…

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Magnetohydrodynamic accretion disk simulations suggest that much of the energy liberated by the magnetorotational instability (MRI) can be channeled into large-scale toroidal magnetic fields through dynamo action. Under certain conditions,…

High Energy Astrophysical Phenomena · Physics 2015-08-19 Mitchell C. Begelman , Philip J. Armitage , Christopher S. Reynolds

Context. Observations of Zeeman split spectral lines represent an important approach to derive the structure and strength of magnetic fields in molecular clouds. In contrast to the uncertainty of the spectral line observation itself, the…

Astrophysics of Galaxies · Physics 2017-05-10 R. Brauer , S. Wolf , S. Reissl , F. Ober

We carried out 2.5-dimensional resistive magnetohydrodynamic simulations to study the effects of magnetic diffusivity on magnetically driven mass accretion and jet formation. We found that (1) when the normalized magnetic diffusivity, is…

Astrophysics · Physics 2015-06-24 T. Kuwabara , K. Shibata , R. Matsumoto

Context. Magnetically arrested disks are among the most suitable candidates for describing the gas accretion and observed emission in the vicinity of supermassive black holes. Aims. This work aims to provide a direct correlation between the…

High Energy Astrophysical Phenomena · Physics 2025-04-02 Eleni Antonopoulou , Argyrios Loules , Antonios Nathanail

The measurement of Zeeman splitting in spectral lines---both in emission and absorption---can provide direct estimates of the magnetic field strength and direction in atomic and molecular clouds, both in our own Milky Way and in external…

We present our second paper describing multi-wave-band, time-resolved spectroscopy of WZ Sge. We analyze the evolution of both optical and IR emission lines throughout the orbital period and find evidence, in the Balmer lines, for an…

Astrophysics · Physics 2015-06-24 E. Mason , W. Skidmore , S. B. Howell , D. R. Ciardi , S. Littlefair , V. S. Dhillon

The origin of the rapid quasi-periodic variabilities observed in a number of accreting black hole X-ray binaries is not understood. It has been suggested that these variabilities are associated with diskoseismic oscillation modes of the…

Astrophysics · Physics 2011-02-11 Wen Fu , Dong Lai

We present MHD simulations exploring the launching, acceleration and collimation of jets and disk winds. The evolution of the disk structure is consistently taken into account. Extending our earlier studies, we now consider the…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Deniss Stepanovs , Christian Fendt , Somayeh Sheikhnezami

Magnetic fields are important for accretion disc structure. Magnetic fields in a disc system may be transported with the accreted matter. They can be associated with either the central body and/or jet, and be fossil or dynamo excited in…

High Energy Astrophysical Phenomena · Physics 2016-03-23 David Moss , Dmitri Sokoloff , Valery Suleimanov

A sample of 17 FR I radio galaxies constructed from the 3CR catalog, which is characterized by edge-darkened radio structures, is studied. The optical core luminosities derived from Hubble Space Telescope observation are used to estimate…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-25 Han He , Bei You , Ning Jiang , Xinwu Cao , Jingfu Hu , Zhenfeng Sheng , Su Yao , Bozena Czerny

We present two-temperature, radiative general relativistic magnetohydrodynamic simulations of Magnetically Arrested Discs (MAD) that launch powerful relativistic jets. The mass accretion rates of our simulations are scaled to match the…

High Energy Astrophysical Phenomena · Physics 2019-04-11 Andrew Chael , Ramesh Narayan , Michael D. Johnson

Context: The role of magnetic fields during high-mass star formation is a matter of fierce debate, yet only a few direct probes of magnetic field strengths are available. Aims: The magnetic field is detected in a number of massive…

Astrophysics · Physics 2009-11-13 W. H. T. Vlemmings

Using high-resolution general relativistic magnetohydrodynamic (GRMHD) simulations, we investigate accretion flows around spinning black holes and identify three distinct accretion states. Our results suggest the origin of the complex…

High Energy Astrophysical Phenomena · Physics 2026-02-25 Rohan Raha , Banibrata Mukhopadhyay , Koushik Chatterjee

Activity of the nuclei of galaxies and stellar mass systems involving disk accretion to black holes is thought to be due to (1) a small-scale turbulent magnetic field in the disk (due to the magneto-rotational instability or MRI) which…

High Energy Astrophysical Phenomena · Physics 2009-08-05 R. V. E. Lovelace , D. M. Rothstein , G. S. Bisnovatyi-Kogan

We present a unified interpretation of experimentally observed magnetic circular dichroism (MCD) in the ferromagnetic semiconductor (Ga,Mn)As, based on theoretical arguments, which demonstrates that MCD in this material arises primarily…

Almost three decades ago, Mathys (1990) demonstrated the importance of studying Ap stars showing resolved Zeeman split Fe II 6147.7 and 6149.2 lines. Such Zeeman split lines can be seen in stars whose projected rotational velocity is…

Solar and Stellar Astrophysics · Physics 2018-12-11 S. Hubrig , S. P. Jarvinen , M. Schöller , J. F. Gonzalez

We perform local, vertically stratified shearing-box MHD simulations of protoplanetary disks (PPDs) at a fiducial radius of 1 AU that take into account the effects of both Ohmic resistivity and ambipolar diffusion (AD). The magnetic…

Earth and Planetary Astrophysics · Physics 2015-06-12 Xue-Ning Bai , James M. Stone

X-ray reverberation has proven to be a powerful tool capable of probing the innermost region of accretion disks around compact objects. Current theoretical effort generally assumes that the disk is geometrically thin, optically thick and…

Astrophysics of Galaxies · Physics 2019-10-11 Lars Lund Thomsen , Jane Lixin Dai , Enrico Ramirez-Ruiz , Erin Kara , Chris Reynolds

The conventional accretion disk lore is that magnetized turbulence is the principal angular momentum transport process that drives accretion. However, when dynamically important large-scale magnetic fields thread an accretion disk, they can…

High Energy Astrophysical Phenomena · Physics 2024-04-24 Vikram Manikantan , Nicholas Kaaz , Jonatan Jacquemin-Ide , Gibwa Musoke , Koushik Chatterjee , Matthew Liska , Alexander Tchekhovskoy

Fraction of hot stars posses strong magnetic fields that channel their radiatively driven outflows. We study the influence of line splitting in the magnetic field (Zeeman effect) on the wind properties. We use our own global wind code with…

Solar and Stellar Astrophysics · Physics 2018-12-19 J. Krticka