{"title":"Time Structure of the Average Rotation Measure for Accretion Disk in Shearing Box Approximation","authors":"M. A. Buldakov, A. S. Andrianov","doi":"10.1134/S1063772924700495","DOIUrl":null,"url":null,"abstract":"<p>Temporal structure of the average rotation measure and the evolution of energetic characteristics of accretion disk in a shearing box approximation are considered. The temporal structure of rotation measure consists of both low- and high-frequency alternating sign oscillations. The mechanisms responsible for these oscillations and their connection with the disk dynamo are discussed. The 2D distributions and the vertical structure of rotation measure and magnetic energy are analysed for times corresponding to extrema and close to zero values of rotation measure. It is shown that the extrema of rotation measure are formed on account of several individual turbulent structures with large amplitudes that are related to magnetorotational and Parker instabilities. It is found that the spatial locations of these structures correspond to areas with high local magnetic energy. The possibility of estimating the period of disk dynamo using measurements of rotation measure is discussed. Cases of Sgr A* and M87* are considered.</p>","PeriodicalId":55440,"journal":{"name":"Astronomy Reports","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Astronomy Reports","FirstCategoryId":"101","ListUrlMain":"https://link.springer.com/article/10.1134/S1063772924700495","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
Temporal structure of the average rotation measure and the evolution of energetic characteristics of accretion disk in a shearing box approximation are considered. The temporal structure of rotation measure consists of both low- and high-frequency alternating sign oscillations. The mechanisms responsible for these oscillations and their connection with the disk dynamo are discussed. The 2D distributions and the vertical structure of rotation measure and magnetic energy are analysed for times corresponding to extrema and close to zero values of rotation measure. It is shown that the extrema of rotation measure are formed on account of several individual turbulent structures with large amplitudes that are related to magnetorotational and Parker instabilities. It is found that the spatial locations of these structures correspond to areas with high local magnetic energy. The possibility of estimating the period of disk dynamo using measurements of rotation measure is discussed. Cases of Sgr A* and M87* are considered.
期刊介绍:
Astronomy Reports is an international peer reviewed journal that publishes original papers on astronomical topics, including theoretical and observational astrophysics, physics of the Sun, planetary astrophysics, radio astronomy, stellar astronomy, celestial mechanics, and astronomy methods and instrumentation.