A5014183531- Astrophysical Phenomena and Observations
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Solar and Space Plasma Dynamics
- Pulsars and Gravitational Waves Research
- Ionosphere and magnetosphere dynamics
- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Mechanics and Biomechanics Studies
- Fluid Dynamics and Turbulent Flows
- Geomagnetism and Paleomagnetism Studies
- Magnetic confinement fusion research
- Corporate Taxation and Avoidance
- Scientific Research and Discoveries
- Gyrotron and Vacuum Electronics Research
- Advanced Thermodynamic Systems and Engines
- Nuclear Physics and Applications
- Refrigeration and Air Conditioning Technologies
- Market Dynamics and Volatility
- Radio Astronomy Observations and Technology
- Heat Transfer Mechanisms
- Nuclear Materials and Properties
New Mexico Consortium
2020-2024
Los Alamos National Laboratory
2022-2023
Shanghai Astronomical Observatory
2012-2022
Columbia University
2019-2022
Astronomical Observatory
2015
Chinese Academy of Sciences
2013
Huazhong University of Science and Technology
2005-2012
Previous MHD simulations have shown that wind must exist in black hole hot accretion flows. In this paper, we continue our study by investigating the detailed properties of wind, such as mass flux and poloidal speed, mechanism production. For aim, make use a three dimensional GRMHD simulation flows around Schwarzschild hole. The is designed so magnetic not accumulated significantly To distinguish real from turbulent outflows, track trajectories virtual Largrangian particles data. We find two...
We investigate the effects of AGN feedback on cosmological evolution an isolated elliptical galaxy by performing two-dimensional high-resolution hydrodynamical numerical simulations. The inner boundary simulation is chosen so that Bondi radius resolved. Compared to previous works, two accretion modes, namely hot and cold, which correspond different rates have radiation wind outputs, are carefully discriminated in each mode taken into account. most updated physics, including descriptions from...
Recent observations and theoretical work on gamma-ray bursts favor the central engine model of a Kerr black hole (BH) surrounded by magnetized neutrino-dominated accretion flow (NDAF). The magnetic coupling between BH disk through large-scale closed field exerts torque transports rotational energy from to disk. We investigate properties NDAF with this torque. For rapid spinning BH, transfers enormous into inner There are two consequences: (1) luminosity neutrino annihilation is greatly...
A new relativistic vortex cutter driven by the Laguerre-Gaussian (LG) mode is carried out for first time in three-dimensional particle-in-cell simulations. Studies show that electric fields periodically concentrate and emanate within every laser wavelength reflected circularly polarized LG_{p}^{l} (p=0, l=1, σ_{z}=-1) laser, which works just like a cutter, resulting ultrashort collimated electron cluster with constant period space. single particle model given verifies formation has close...
We study the existence and property of Fast magnetosonic modes in 3D compressible MHD turbulence by carrying out a number simulations with incompressible driving conditions. use two approaches to determine presence modes: mode decomposition based on spatial variations only spatio-temporal 4D-FFT analysis all fluctuations. The latter method enables us quantify fluctuations that satisfy dispersion relation finite frequency. Overall, we find fraction identified via 4D FFT approach total...
Based on two-dimensional high resolution hydrodynamic numerical simulation, we study the mechanical and radiative feedback effects from central AGN cosmological evolution of an isolated elliptical galaxy. Physical processes such as star formation supernovae are considered. The inner boundary simulation domain is carefully chosen so that fiducial Bondi radius resolved accretion rate black hole determined self-consistently. In analogy to previous works, assume specific angular momentum galaxy...
ABSTRACT Numerical simulations of hot accretion flows around black holes have shown the existence strong wind. Those works focused only on region close to hole and thus it is unknown whether or where wind production stops at large radii. To address this question, we recently performed hydrodynamic (HD) by taking into account gravitational potential both nuclear star cluster. The latter assumed be proportional <?CDATA ${\sigma }^{2}\mathrm{ln}(r)$?> , with σ being velocity dispersion stars r...
Previous works show strong winds exist in hot accretion flows around black holes. Those focus only on the region close to hole thus it is unknown whether or where wind production stops at large radii. In this paper, we investigate problem by hydrodynamical simulations. We take into account gravities of both and nuclear star clusters. For latter, assume that velocity dispersion stars a constant its gravitational potential $\propto \sigma^2 \ln (r)$, $\sigma$ $r$ distance from center galaxy....
In a previous work, we have shown that the formation of Fermi bubbles can be due to interaction between winds launched from hot accretion flow in Sgr A* and interstellar medium (ISM). focus only on morphology. this paper continue our study by calculating gamma-ray radiation. Some cosmic ray protons (CRp) electrons must contained winds, which are likely formed physical processes such as magnetic reconnection. We performed MHD simulations spatial distribution CRp, considering advection...
Understanding how galaxies maintain the inefficiency of star formation with physically self-consistent models is a central problem for galaxy evolution. Although numerous theoretical have been proposed in recent decades, debate still exists. By means high-resolution two-dimensional hydrodynamical simulations, we study three feedback effects (the stellar wind heating, SNe feedback, and AGN feedback) suppressing activities on evolution early-type different masses. are updated based...
Abstract This is the second paper of our series works studying effects active galactic nuclei (AGNs) feedback on cosmological evolution an isolated elliptical galaxy by performing two-dimensional hydrodynamical simulations. Compared to previous works, main improvement here that we adopt most up-to-date AGN physics, which described in detail first paper, including discrimination two accretion modes and descriptions wind radiation modes. In Paper I, consider case specific angular momentum gas...
Abstract Many questions remain about the compressibility of solar wind turbulence with respect to its origins and properties. Low plasma beta (ratio thermal magnetic pressure) environments allow for easier generation compressible turbulence, enabling study relationship between density fluctuations turbulent Mach number. Utilizing Parker Solar Probe data, we examine normalized proton <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo...
We investigate state transitions in black hole X-ray binaries through different parameters by using two-dimensional axisymmetric hydrodynamical simulation method. For radiative cooling hot accretion flow, we take into account the bremsstrahlung, synchrotron and self-Comptonization self-consistently dynamics. Our main result is that occur when rate reaches a critical value |$\dot{M} \sim 3\alpha \ \dot{M}_{\rm Edd}$|, above which cold dense clumpy/filamentary structures are formed, embedded...
We perform time-dependent, 2DHD numerical simulations to study the dynamics of a slowly rotating accretion flow from sub-pc pc scales under irradiation central AGN. Compared previous work, we improve calculation radiative force due X-rays. More importantly, in addition pressure and heating/cooling directly AGN, momentum equation also include scattered reprocessed photons. find that properties change significantly this "re-radiation" effect. The inflow rate at inner boundary is reduced, while...
Abstract Based on our previous modeling of active galactic nucleus (AGN) feedback in isolated elliptical galaxies using the MACER (Massive AGN Controlled Ellipticals Resolved) code, we extend and improve model to include rotation, facilitate angular momentum transfer via Toomre instability gaseous disks, limit star formation regions high density low temperature, treatment hot-mode (low accretion rate) feedback. The galaxy now has an extended dark matter profile that matches with standard...
Abstract The distinctive morphology of head–tail radio galaxies reveals strong interactions between the jets and their intra-cluster environment, general consensus on origin sources is that are bent by violent weather. We demonstrate in this paper such provide a great opportunity to study jet properties also dynamics medium (ICM). By three-dimensional magnetohydrodynamical simulations, we analyze detailed bending process magnetically dominated jet, based magnetic tower model. use stratified...
We perform two-dimensional simulations to study how the wind strength changes with accretion rate. take into account bremsstrahlung, synchrotron radiation and Comptonization. find that when rate is low, radiative cooling not important, flow hot. For hot flow, very strong. The mass flux of can be ∼ 50 per cent inflow When increases a value at which roughly equal or slightly larger than viscous heating rate, cold clumps form around equatorial plane. In this case, gas pressure gradient force...
The solar wind is a magnetized and turbulent plasma. Its turbulence often dominated by Alfv\'enic fluctuations deemed as nearly incompressible far away from the Sun, shown in-situ measurements near 1AU. However, for closer to plasma $\beta$ decreases (often lower than unity) while Mach number $M_t$ increases (can approach unity, e.g., transonic fluctuations). These conditions could produce significantly more compressible effects, characterized enhanced density fluctuations, seen several...
Solar wind turbulence is often perceived as weakly compressible and the density fluctuations remain poorly understood both theoretically observationally. Compressible magnetohydrodynamic simulations provide useful insights into nature of fluctuations. We discuss a few important effects related to 3D in-situ observations. The observed quantities such power spectrum variance depend on angle between sampling trajectory mean magnetic field due anisotropy turbulence. effect stronger at smaller...
Abstract We present a spatial filtering (or coarse-graining) analysis on 3D magnetized magnetohydrodynamic (MHD) turbulence simulations. The filtered compressible MHD formulae show transfer of kinetic and magnetic energies from large to small scales, as well energy conversion between kinetic, magnetic, thermal energies. anisotropic enables separate analyses the flows perpendicular parallel global mean field. Anisotropy in cascade is demonstrated by larger rate also wavenumbers associated...
This new era of multi-messenger astronomy, which will mature in the next decade, offers us unprecedented opportunity to combine more than one messenger solve some long-standing puzzles AGN jet physics. We advocate support future instruments with large effective areas, excellent timing resolution, and wide fields view.
Abstract We add a suite of chemical abundances to the MACER (Massive AGN Controlled Ellipticals Resolved) 2D code, by solving 12 additional continuity equations for H, He, C, N, O, Ne, Mg, Si, S, Ca, Fe, and Ni with sources from AGB stars Type Ia II supernovae metal yields based on standard stellar physics. New stars, formed in Toomre unstable circumnuclear disks (of size ≲150 pc), are assumed have top-heavy initial mass function power index 1.65. The dilution effects due cosmic accretion...
We propose a model of magnetic connection (MC) black hole with its surrounding accretion disc based on large-scale field. The MC gives rise to transport energy and angular momentum between the disc, closed field lines pipe hot matter evaporated from shape it in corona above form magnetically induced disc-corona system, which has same configuration as numerically solve dynamic equations context Kerr metric, is determined by dynamo process equipartition pressure gas pressure. Thus we can...
We apply epicyclic resonances to the magnetic connection (MC) of a black hole (BH) with relativistic accretion disc, interpreting high frequency quasi-periodic oscillations (HFQPOs) 3:2 pairs observed in three BH X-ray binaries. It turns out that HFQPO are associated steep power-law states, and severe damping can be overcome by transferring energy angular momentum from spinning inner disc MC process.
In extremely low accretion rate systems, the ion mean-free path can be much larger than gyroradius. Therefore, gas pressure is anisotropic with respect to magnetic field lines. The effects of anisotropy modeled by an viscosity Angular momentum transferred viscosity. this paper, we investigate hot flow We consider case that viscous stress Maxwell stress. find convectively unstable. also mass inflow decreases towards a black hole. Wind very weak; its flux 10−15% rate. inward decrease mainly...