Faraday tomography: a new, three-dimensional probe of the interstellar magnetic field

15th Annual International Astrophysics Conference: "The Science of Ed Stone: Celebrating his 80th Birthday"

物理学;天文学

Ferrière, Katia^1

IRAP, Université de Toulouse, CNRS, 9 avenue du Colonel Roche, BP 44346, Toulouse Cedex 4

F-31028, France^1

关键词: Interstellar magnetic fields;    Interstellar mediums;    Linearly polarized;    Radio wavelengths;    Rotation measure synthesis;    Synchrotron emission;    Three dimensional probes;    Three dimensions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/767/1/012006/pdf
DOI  :  10.1088/1742-6596/767/1/012006

学科分类：天文学(综合)

来源: IOP

【 摘 要 】

Much of our present observational knowledge of the interstellar magnetic field of our Galaxy comes from two different sources, both of which involve mechanisms operating at radio wavelengths: the first one is the Faraday rotation of linearly-polarized radio waves propagating through the magneto-ionic interstellar medium, and the second one is the diffuse synchrotron emission from our Galaxy. I will review what these two classical probes have taught us about the strength, the direction/orientation, and the spatial distribution of the interstellar magnetic field. I will then present a recent method, known as Faraday tomography or rotation measure synthesis, which relies on a combination of Faraday rotation and synchrotron emission and which makes it possible to probe the interstellar magnetic field in three dimensions.