{"title":"Density-gradient-driven drift waves in the solar corona","authors":"M. Brchnelova, M. J. Pueschel, S. Poedts","doi":"10.1063/5.0223417","DOIUrl":null,"url":null,"abstract":"It has been suggested that under solar coronal conditions, drift waves may contribute to coronal heating. Specific properties of the drift waves to be expected in the solar corona have, however, not yet been determined using more advanced numerical models. We investigate the linear properties of density-gradient-driven drift waves in the solar coronal plasma using gyrokinetic ion–electron simulations with the gyrokinetic code Gene, solving the Vlasov–Maxwell equations in five dimensions assuming a simple slab geometry. We determine the frequencies and growth rates of the coronal density gradient-driven drift waves with changing plasma parameters, such as the electron β, the density gradient, the magnetic shear, and additional temperature gradients. To investigate the influence of the finite Larmor radius effect on the growth and structure of the modes, we also compare the gyrokinetic simulation results to those obtained from drift-kinetics. In most of the investigated conditions, the drift wave has positive growth rates that increase with increasing density gradient and decreasing β. In the case of increasing magnetic shear, we find that from a certain point, the growth rate reaches a plateau. Depending on the considered reference environment, the frequencies and growth rates of these waves lie on the order of 0.1 mHz–1 Hz. These values correspond to the observed solar wind density fluctuations near the Sun detected by WISPR, currently of unexplained origin. As a next step, nonlinear simulations are required to determine the expected fluctuation amplitudes and the plasma heating resulting from this mechanism.","PeriodicalId":20175,"journal":{"name":"Physics of Plasmas","volume":null,"pages":null},"PeriodicalIF":2.0000,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physics of Plasmas","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1063/5.0223417","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, FLUIDS & PLASMAS","Score":null,"Total":0}
引用次数: 0
Abstract
It has been suggested that under solar coronal conditions, drift waves may contribute to coronal heating. Specific properties of the drift waves to be expected in the solar corona have, however, not yet been determined using more advanced numerical models. We investigate the linear properties of density-gradient-driven drift waves in the solar coronal plasma using gyrokinetic ion–electron simulations with the gyrokinetic code Gene, solving the Vlasov–Maxwell equations in five dimensions assuming a simple slab geometry. We determine the frequencies and growth rates of the coronal density gradient-driven drift waves with changing plasma parameters, such as the electron β, the density gradient, the magnetic shear, and additional temperature gradients. To investigate the influence of the finite Larmor radius effect on the growth and structure of the modes, we also compare the gyrokinetic simulation results to those obtained from drift-kinetics. In most of the investigated conditions, the drift wave has positive growth rates that increase with increasing density gradient and decreasing β. In the case of increasing magnetic shear, we find that from a certain point, the growth rate reaches a plateau. Depending on the considered reference environment, the frequencies and growth rates of these waves lie on the order of 0.1 mHz–1 Hz. These values correspond to the observed solar wind density fluctuations near the Sun detected by WISPR, currently of unexplained origin. As a next step, nonlinear simulations are required to determine the expected fluctuation amplitudes and the plasma heating resulting from this mechanism.
期刊介绍:
Physics of Plasmas (PoP), published by AIP Publishing in cooperation with the APS Division of Plasma Physics, is committed to the publication of original research in all areas of experimental and theoretical plasma physics. PoP publishes comprehensive and in-depth review manuscripts covering important areas of study and Special Topics highlighting new and cutting-edge developments in plasma physics. Every year a special issue publishes the invited and review papers from the most recent meeting of the APS Division of Plasma Physics. PoP covers a broad range of important research in this dynamic field, including:
-Basic plasma phenomena, waves, instabilities
-Nonlinear phenomena, turbulence, transport
-Magnetically confined plasmas, heating, confinement
-Inertially confined plasmas, high-energy density plasma science, warm dense matter
-Ionospheric, solar-system, and astrophysical plasmas
-Lasers, particle beams, accelerators, radiation generation
-Radiation emission, absorption, and transport
-Low-temperature plasmas, plasma applications, plasma sources, sheaths
-Dusty plasmas