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相关论文: Tracing interstellar magnetic field using velocity…

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The mean plane-of-sky magnetic field strength is traditionally obtained from the combination of polarization and spectroscopic data using the Davis-Chandrasekhar-Fermi (DCF) technique. However, we identify the major problem of the DCF to be…

星系天体物理 · 物理学 2022-08-31 A. Lazarian , Ka Ho Yuen , Dmitri Pogosyan

We discuss inverse problem of detection turbulence magnetic field helical properties using radio survey observations statistics. In this paper, we present principal solution which connects magnetic helicity and correlation between Faraday…

天体物理仪器与方法 · 物理学 2010-01-19 A. Volegova , R. Stepanov

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)…

星系天体物理 · 物理学 2023-08-02 Sunil Malik , Ka Ho Yuen , Huirong Yan

Recent studies provide evidence for the multi-scale nature of magnetic turbulence in the plasma sheet. Wavelet methods represent modern time series analysis techniques suitable for the description of statistical characteristics of…

空间物理 · 物理学 2016-09-08 W. Baumjohann , R. Nakamura , A. Runov , M. Volwerk , T. L. Zhang , A. Balogh

Magnetic field lines in interstellar media have a rich morphology, which could be characterized by geometrical parameters such as curvature and torsion. In this paper, we explore the statistical properties of magnetic field line curvature…

星系天体物理 · 物理学 2020-08-05 Ka Ho Yuen , A. Lazarian

Magnetic fields (B-fields) are ubiquitous in the interstellar medium (ISM), and they play an essential role in the formation of molecular clouds and subsequent star formation. However, B-fields in interstellar environments remain…

星系天体物理 · 物理学 2024-10-18 Archana Soam , Ka Ho Yuen , Ian Stephens , Chi Yan Law , Ka Wai Ho , Simon Coudé

The strong alignment of small-scale turbulent Alfv\'enic motions with the direction of the magnetic field that percolates the small-scale eddies and imprints the direction of the magnetic field is a property that follows from the MHD theory…

星系天体物理 · 物理学 2021-04-20 Ka Wai Ho , Alex Lazarian

Due to the inevitable accumulation of the observed information in the direction of the line of sight, it is difficult to measure the local magnetic field of MHD turbulence. However, the correct understanding of the local magnetic field is a…

高能天体物理现象 · 物理学 2020-05-27 Jian-Fu Zhang , Ke Hu , Jungyeon Cho , Alex Lazarian

We demonstrate the utility of the bispectrum, the Fourier three-point correlation function, for studying driving scales of magnetohydrodynamic (MHD) turbulence in the interstellar medium. We calculate the bispectrum by implementing a…

星系天体物理 · 物理学 2022-05-25 Michael J. O'Brien , Blakesley Burkhart , Michael J. Shelley

We introduce two new ways of obtaining the strength of plane-of-sky (POS) magnetic field by simultaneous use of spectroscopic Doppler-shifted lines and the information on magnetic field direction. The latter can be obtained either through…

星系天体物理 · 物理学 2020-02-20 Alex Lazarian , Ka Ho Yuen , Dmitri Pogosyan

In modern cosmology, many efforts have been put to detect primordial B-mode of cosmic microwave background (CMB) polarization from the gravitational waves generated during inflation. Considering the foreground dust contamination of…

星系天体物理 · 物理学 2020-06-17 Zekun Lu , A. Lazarian , Dmitri Pogosyan

The investigation of the statistical properties of maps of line centroids has been used for almost 50 years, but there is still no general agreement on their interpretation. We try to quantify which properties of underlying turbulent…

天体物理学 · 物理学 2009-11-11 V. Ossenkopf , A. Esquivel , A. Lazarian , J. Stutzki

We investigate the alignment mechanism between the magnetic field and interstellar clouds formed by the collision of warm atomic gas. We find that the magnetic field, initially oriented parallel to the flow, is perturbed by a fast MHD…

星系天体物理 · 物理学 2025-02-26 Guido Granda-Muñoz , Enrique Vázquez-Semadeni , Gilberto C. Gómez

The strengths of magnetic fields in interstellar gas clouds are obtained through observations of the circular polarization of spectral line radiation. Irregularities in this magnetic field may be present due to turbulence, waves or perhaps…

天体物理学 · 物理学 2009-10-31 W. D. Watson , D. S. Wiebe , R. M. Crutcher

3D Galactic magnetic fields are critical for understanding the interstellar medium, Galactic foreground polarization, and the propagation of ultra-high-energy cosmic rays. Leveraging recent theoretical insights into anisotropic…

星系天体物理 · 物理学 2025-07-23 Yue Hu

The Planck mission will permit measurements of the polarization of the cosmic microwave background and of polarized foregrounds such as our own Galaxy with an unprecedented combination of accuracy and completeness. This will provide…

天体物理学 · 物理学 2009-11-11 Torsten A. Ensslin , Corina Vogt , Andre Waelkens , Alexander A. Schekochihin

We describe a new technique for probing galactic and extragalactic 2D and 3D magnetic field distribution using gradients of polarized synchrotron emission. The fluctuations of magnetic field are elongated along the ambient magnetic field.…

星系天体物理 · 物理学 2018-10-10 A. Lazarian , Ka Ho Yuen

Recent observations revealed that small magnetic elements abundant at the solar surface move poleward with a velocity which seems to be lower than the plasma velocity $U_{\theta}$. Guerrero et al. (2011) explained this discrepancy as a…

太阳与恒星天体物理 · 物理学 2015-06-03 G. Guerrero , M. Rheinhardt , M. Dikpati

The Galactic neutral hydrogen (HI) sky at high Galactic latitudes is suffused with linear structure. Particularly prominent in narrow spectral intervals, these linear HI features are well aligned with the plane-of-sky magnetic field…

星系天体物理 · 物理学 2018-04-18 S. E. Clark

Magnetic fields and turbulence are fundamental to the evolution of galaxies, yet their precise measurement and analysis present significant challenges. The recently developed Velocity Gradient Technique (VGT), which capitalizes on the…

星系天体物理 · 物理学 2025-03-07 Yue Hu , Joseph Whittingham , A. Lazarian , Christoph Pfrommer , Siyao Xu , Thomas Berlok