English
Related papers

Related papers: Velocity Gradients as a Tracer for Magnetic Fields

200 papers

We present simultaneous experimental measurements of the dynamics of anisotropic particles transported by a turbulent flow and the velocity gradient tensor of the flow surrounding them. We track both rod-shaped particles and small spherical…

Fluid Dynamics · Physics 2015-06-23 Rui Ni , Stefan Kramel , Nicholas T. Ouellette , Greg A. Voth

We present results obtained from a finite-element simulation of seismic displacement fields and of gravity gradients generated by those fields. The displacement field is constructed by a plane wave model with a 3D isotropic stochastic field…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Jan Harms , Riccardo DeSalvo , Steven Dorsher , Vuk Mandic

Magnetic fields are crucial in numerous astrophysical processes within the interstellar medium. However, the detailed determination of magnetic field geometry is notoriously challenging. Based on the modern magnetohydrodynamic (MHD)…

Astrophysics of Galaxies · Physics 2023-08-02 Sunil Malik , Ka Ho Yuen , Huirong Yan

The dynamical state of star-forming molecular clouds cannot be understood without determining the structure and strength of their magnetic fields. Measurements of polarized far-infrared radiation from thermally aligned dust grains are used…

Astrophysics · Physics 2009-11-06 F. Heitsch , E. G. Zweibel , M. -M. Mac Low , P. S. Li , M. L. Norman

Characterizing turbulence in protoplanetary disks is crucial for understanding how they accrete and spawn planets. Recent measurements of spectral line broadening promise to diagnose turbulence, with different lines probing different…

Earth and Planetary Astrophysics · Physics 2015-06-19 Ji-Ming Shi , Eugene Chiang

We investigate the anisotropy of Alfv\'enic turbulence in the inertial range of slow solar wind and in both driven and decaying reduced magnetohydrodynamic simulations. A direct comparison is made by measuring the anisotropic second-order…

Space Physics · Physics 2012-08-20 C. H. K. Chen , A. Mallet , T. A. Yousef , A. A. Schekochihin , T. S. Horbury

The effect of an external guide field on the turbulence-like properties of magnetic reconnection is studied using five different 2.5D kinetic particle-in-cell (PIC) simulations. The magnetic energy spectrum is found to exhibit a slope of…

Parker Solar Probe and Solar Orbiter data are used to investigate the radial evolution of magnetic turbulence between $0.06 ~ \lesssim R ~\lesssim 1$ au. The spectrum is studied as a function of scale, normalized to the ion inertial scale…

Interaction of three-dimensional magnetic fields, turbulence, and self-gravity in the molecular cloud is crucial in understanding star formation but has not been addressed so far. In this work, we target the low-mass star-forming region…

Astrophysics of Galaxies · Physics 2023-07-26 Yue Hu , Alex Lazarian

Estimates of velocities from time series of photospheric and/or chromospheric vector magnetograms can be used to determine fluxes of magnetic energy (the Poynting flux) and helicity across the magnetogram layer, and to provide…

Astrophysics · Physics 2007-10-03 B. T. Welsch , G. H. Fisher

Many phenomena taking place in the solar photosphere are controlled by plasma motions. Although the line-of-sight component of the velocity can be estimated using the Doppler effect, we do not have direct spectroscopic access to the…

Solar and Stellar Astrophysics · Physics 2017-08-02 A. Asensio Ramos , I. S. Requerey , N. Vitas

Simulations are performed to investigate turbulent properties of nonlinearly interacting two-dimensional (2D) magnetic electron drift vortex (MEDV) modes in a nonuniform unmagnetized plasma. The relevant nonlinear equations governing the…

Plasma Physics · Physics 2015-05-13 Dastgeer Shaikh , P. K. Shukla

We discuss an extension of the velocity Verlet method that accurately approximates the kinetic-energy-conserving charged particle motion that comes from magnetic forcing. For a uniform magnetic field, the method is shown to conserve both…

Classical Physics · Physics 2021-02-03 A. Chambliss , J. Franklin

The turbulent magnetic fields of a large set of fast solar wind streams measured onboard ACE and STEREO A and B are analyzed in an effort to identify the effects of the turbulence-level broad variations on the orientations of the local,…

Solar and Stellar Astrophysics · Physics 2013-12-18 B. R. Ragot

Turbulence is a complex physical process prevalent in modern physics, particularly in ionized environments like interstellar gas, where magnetic fields play a dynamic role. However, the precise influence of magnetic fields in such settings…

Astrophysics of Galaxies · Physics 2025-08-12 Guang-Xing Li , Mengke Zhao

We consider a measure of the peculiar velocity field derived from the Mark III compilation of 2900 spiral galaxies (Willick \etal 1996b), using an analysis that is substantially free of bias (Nusser and Davis 1995). We expand the velocity…

Astrophysics · Physics 2009-10-28 Marc Davis , Adi Nusser , Jeff Willick

The mapping of the Galactic Magnetic Field (GMF) in three dimensions is essential to comprehend various astrophysical processes that occur within the Milky Way. This study endeavors to map the GMF by utilizing the latest MM2 technique, the…

Astrophysics of Galaxies · Physics 2023-07-12 Yue Hu , Alex Lazarian

The dynamics of the interstellar medium (ISM) are strongly affected by turbulence, which shows increased anisotropy in the presence of a magnetic field. We expand upon the Esquivel & Lazarian method to estimate the Alfven Mach number using…

Astrophysics of Galaxies · Physics 2015-06-22 Blakesley Burkhart , A. Lazarian , I. C. Leao , J. R. de Medeiros , A. Esquivel

Anticipating the motion of other road users is crucial for automated driving systems (ADS), as it enables safe and informed downstream decision-making and motion planning. Unfortunately, contemporary learning-based approaches for motion…

Machine Learning · Computer Science 2023-09-21 MReza Alipour Sormoli , Amir Samadi , Sajjad Mozaffari , Konstantinos Koufos , Mehrdad Dianati , Roger Woodman

The shape gradient is a local sensitivity function that provides the change in a figure of merit associated with a perturbation to the shape of the object. The shape gradient can be used for gradient-based optimization, sensitivity…

Plasma Physics · Physics 2020-01-29 Elizabeth J. Paul , Thomas Antonsen, , Matt Landreman , W. Anthony Cooper
‹ Prev 1 3 4 5 6 7 10 Next ›