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Related papers: Tracing Magnetic Fields with the Gradient Techniqu…

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Magnetic fields are ubiquitous in the interstellar medium but are notoriously difficult to study through observation. Making use of the advances in our understanding of MHD turbulence and turbulent reconnection, the Velocity Gradient…

Astrophysics of Galaxies · Physics 2020-01-08 Yue Hu , Ka Ho Yuen , Alex Lazarian

The gradient technique is a promising tool with theoretical foundations based on the fundamental properties of MHD turbulence and turbulent reconnection. Its various incarnations use spectroscopic, synchrotron, and intensity data to trace…

Astrophysics of Galaxies · Physics 2024-06-04 Alex Lazarian , Ka Ho Yuen , Dmitri Pogosyan

Probing magnetic fields in self-gravitating molecular clouds are generally difficult even with the use of the polarimetry. Based on the properties of magneto-hydrodynamic (MHD) turbulence and turbulent reconnection, Velocity Gradient…

Astrophysics of Galaxies · Physics 2019-03-01 Cheng-Han Hsieh , Yue Hu , Shih-Ping Lai , Ka Ho Yuen , Sheng-Yuan Liu , I-Ta Hsieh , Ka Wai Ho , Alex Lazarian

Super-Alfvenic turbulence is important for many astrophysical objects, particularly galaxy clusters. In this paper, we explore the accuracy of Synchrotron Intensity Gradients (SIGs) and X-ray intensity gradients to map magnetic fields in…

Astrophysics of Galaxies · Physics 2024-12-04 Ka Wai Ho , Alex Lazarian

This study proceeds with the development of the technique employing velocity gradients that were identified in (\cite{GL17}, henceforth GL17) as a means of probing magnetic field in interstellar media. We demonstrate a number of practical…

Astrophysics of Galaxies · Physics 2017-05-25 Ka Ho Yuen , A. Lazarian

Tracing of the magnetic field with Velocity Gradient Technique (VGT) allows observers to probe magnetic field directions with spectroscopic data. In this paper, we employ the method of Principal Component Analysis (PCA) to extract the…

Astrophysics of Galaxies · Physics 2018-07-25 Yue Hu , Ka Ho Yuen , A. Lazarian

The detection of primordial B-mode polarization is still challenging due to the relatively low amplitude compared to the galactic foregrounds. To remove the contribution from the foreground, a comprehensive picture of the galactic magnetic…

Astrophysics of Galaxies · Physics 2020-07-07 Yue Hu , A. Lazarian

As a novel approach for tracing interstellar magnetic fields, the Velocity Gradient Technique (VGT) has been proven to be effective for probing magnetic fields in the diffuse interstellar medium (ISM). In this work, we verify the VGT in a…

Astrophysics of Galaxies · Physics 2022-01-26 Mingrui Liu , Yue Hu , Alex Lazarian

Recent development of the velocity gradient technique shows the {\toreferee capability} of the technique in the way of tracing magnetic fields morphology in diffuse interstellar gas and molecular clouds. In this paper, we perform the…

Astrophysics of Galaxies · Physics 2023-02-01 Ka Wai Ho , Alex Lazarian

We employ synthetic observations obtained with MHD simulations to study how to trace the distribution of turbulent magnetic fields using the synchrotron polarization gradient techniques suggested by Lazarian \& Yuen (2018). Both synchrotron…

High Energy Astrophysical Phenomena · Physics 2019-05-15 Jian-Fu Zhang , Alex Lazarian , Ka Wai Ho , Ka Ho Yuen , Bo Yang , Yue Hu

Strong Alfv\'enic turbulence develops eddy-like motions perpendicular to the local direction of magnetic fields. This local alignment induces velocity gradients perpendicular to the local direction of the magnetic field. We use this fact to…

Astrophysics of Galaxies · Physics 2017-01-25 Diego F. González-Casanova , A. Lazarian

The central molecular zone (CMZ) plays an essential role in regulating the nuclear ecosystem of our Galaxy. To get an insight into the magnetic fields of the CMZ, we employ the Gradient Technique (GT), which is rooted in the anisotropy of…

Astrophysics of Galaxies · Physics 2022-02-09 Yue Hu , A. Lazarian , Q. Daniel Wang

Magnetic fields are a defining yet enigmatic aspect of the interstellar medium (ISM), with their three-dimensional mapping posing a substantial challenge. In this study, we harness the innovative Velocity Gradient Technique (VGT),…

Astrophysics of Galaxies · Physics 2024-01-15 Tyler Schmaltz , Yue Hu , A. Lazarian

On the basis of the modern understanding of MHD turbulence, we propose a new way of using synchrotron radiation, namely using synchrotron intensity gradients for tracing astrophysical magnetic fields. We successfully test the new technique…

Astrophysics of Galaxies · Physics 2018-03-21 A. Lazarian , Ka Ho Yuen , Hyeseung Lee , Jungyeon Cho

The advancement of our understanding of MHD turbulence opens ways to develop new techniques to probe magnetic fields. In MHD turbulence, the velocity gradients are expected to be perpendicular to magnetic fields and this fact was used by…

Astrophysics of Galaxies · Physics 2017-03-15 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…

Astrophysics of Galaxies · Physics 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…

Astrophysics of Galaxies · Physics 2021-04-20 Ka Wai Ho , Alex Lazarian

We identify velocity channel map intensities as a new way to trace magnetic fields in turbulent media. This work makes use of both of the modern theory of MHD turbulence predicting that the magnetic eddies are aligned with the local…

Astrophysics of Galaxies · Physics 2018-02-07 A. Lazarian , Ka Ho Yuen

This paper studies how to employ synchrotron emission gradient techniques to reveal the properties of the magnetic field within the interstellar media. Based on data cubes of three-dimensional numerical simulations of magnetohydrodynamic…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Jian-Fu Zhang , Qian Liu , Alex Lazarian

Magnetic fields, while ubiquitous in many astrophysical environments, are challenging to measure observationally. Based on the properties of anisotropy of eddies in magnetized turbulence, the Velocity Gradient Technique is a method…

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