Microwave diagnostics of flare plasma by the direct fitting method based on data from the Siberian Radioheliograph
Journal Title: Solar-Terrestrial Physics - Year 2024, Vol 10, Issue 3
Abstract
In this paper, we analyze images and the frequency spectrum of microwave emission in the maximum of brightness distribution in the January 20, 2022 and July 16, 2023 flares recorded by the Siberian Radioheliograph in the 3–6 GHz and 6–12 GHz ranges. We use the obtained spectrum data for radio diagnostics of magnetic field strength and orientation, plasma density, and parameters of accelerated particles in a radio source. The radio diagnostics is carried out by a method based on minimizing the functional containing the intensities of theoretically calculated and observed frequency spectra of left-polarized and right-polarized emission. Since the form of such a multidimensional functional is quite complex, and it is not possible to minimize it by standard approaches, we employ a genetic minimization method. The radio diagnostics allows us to determine features of the dynamics of the magnetic field intensity and orientation, as well as the density and the energy spectral index of non-thermal electrons in the region of maximum brightness of the radio source. We have found that during the growth phase of the main radiation peaks the magnetic field decreases, whereas during the decay phase, on the contrary, it increases. The rate of these changes varies from a few G/s to 11 G/s for the January 20, 2022 flare and is about 1 G/s for the July 16, 2023 flare.
Authors and Affiliations
Smirnov D. A. , Melnikov V. F.
Keywords
Related Articles
- EP ID EP753787
- DOI 10.12737/stp-103202404
- Views 28
- Downloads 0
GENERATION OF ALFVÉN WAVES IN MAGNETIZED PLASMA BY LASER PLASMA BUNCHES AT MACH NUMBERS MUCH LESS THAN UNITY
In this paper, we examine a torsional Alfvén wave produced by periodic plasma bunches in a magnetized plasma flux tube. A new effect has been revealed: the wave is generated not only during the action of bunches, but als...
MONITORING OF GEOMAGNETIC DISTURBANCES USING THE GLOBAL SURVEY METHOD IN REAL TIME
A method for forecasting geomagnetic storms using the realization of the global survey method in real time is presented. The method is based on data from the worldwide network of neutron monitors NMDB. Using this method,...
DIAGNOSTICS OF THE STOCHASTIC IONOSPHERIC CHANNEL IN THE DECAMETER BAND OF RADIO WAVES
We propose a method for direct diagnostics of a stochastic ionospheric radio channel. This method can recalculate probe signal characteristics into transmitted signal characteristics. We derive analytical equations of se...
THE CURRENT STATE OF THE THEORY OF PC1 RANGE ULF PULSATIONS IN MAGNETOSPHERIC PLASMA WITH HEAVY IONS: A REVIEW
The review considers the current state of the theory of short-period ULF waves in plasma with admixture of heavy ions (ions whose mass significantly exceeds the mass of protons). The presence of heavy ions influences the...
CORONAL JETS AS A CAUSE OF MICROWAVE NEGATIVE BURSTS
We have investigated the cause of three “isolated” negative radio bursts recorded one after another at several frequencies in the 1–17 GHz range at the Nobeyama Radio Observatory, Ussuriysk Astrophysical Observatory, and...