Bright ultraviolet knots as possible sources of coherent microwave radiation-Reference-Cited by-同舟云学术

Bright ultraviolet knots as possible sources of coherent microwave radiation

Published:2023-12-28 Issue:4 Volume:9 Page:17-24
ISSN:2500-0535
Container-title:Solar-Terrestrial Physics
language:en
Short-container-title:

Author:

Meshalkina Nataliya¹,Altyntsev Alexander¹

Affiliation:

1. Institute of Solar Terrestrial Physics SB RAS

Abstract

A distinctive feature of the September 6, 2012 event was that sources of narrow-band (2–4 GHz) sub-second pulses (SSP) were observed in small areas of flare loops with so-called bright ultraviolet knots with high plasma density up to 1011 10¹¹ cm⁻³. Time profiles of hard X-rays of the flare, although similar to microwave light curves, do not have structures corresponding to SSP. Analysis of microwave, X-ray, and ultraviolet data has shown that the observable pulses of microwave radiation with a narrow spectral band are coherent in nature and are generated by electrons with energies of several tens of kiloelectronvolt in bright knots at a double plasma frequency. The results of the observations suggest that the appearance of bright knots is associated with local processes of energy release due to interaction of flare loops.

Publisher

Infra-M Academic Publishing House

Subject

Space and Planetary Science,Atmospheric Science,Geophysics

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