English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

This work demonstrates the possibility of magnetic field topologyinvestigations using microwave polarimetric observations. We study a solarflare of GOES M1.7 class that occurred on 11 February, 2014. This flarerevealed a clear signature of spatial inversion of the radio emissionpolarization sign. We show that the observed polarization pattern can beexplained by nonthermal gyrosynchrotron emission from the twisted magneticstructure. Using observations of the Reuven Ramaty High Energy SolarSpectroscopic Imager, Nobeyama Radio Observatory, Radio Solar TelescopeNetwork, and Solar Dynamics Observatory, we have determined the parameters ofnonthermal electrons and thermal plasma and identified the magnetic structurewhere the flare energy release occurred. To reconstruct the coronal magneticfield, we use nonlinear force-free field (NLFFF) and potential magnetic fieldapproaches. Radio emission of nonthermal electrons is simulated by the GXSimulator code using the extrapolated magnetic field and the parameters ofnonthermal electrons and thermal plasma inferred from the observations; themodel radio maps and spectra are compared with observations. We have found thatthe potential magnetic field approach fails to explain the observed circularpolarization pattern; on the other hand, the Stokes $V$ map is successfullyexplained by assuming nonthermal electrons to be distributed along the twistedmagnetic structure determined by the NLFFF extrapolation approach. Thus, weshow that the radio polarization maps can be used for diagnosing the topologyof the flare magnetic structures where nonthermal electrons are injected.

Probing Twisted Magnetic Field Using Microwave Observations in an M Class Solar Flare on 11 February, 2014