coronal magnetic field – Community of European Solar Radio Astronomers

Radio measurements of coronal magnetic fields in fan-spine configurations on the Sun by B. Ryabov and A. Vrublevskis

2023-06-06 73 views

We are striving for more accurate coronal magnetography based on changes in radio polarization as microwaves cross magnetic field lines at nearly right angles. The theory of using quasi-transverse propagation for coronal field measurements includes weak dependence on two parameters: plasma density $N_e$ and the magnetic field divergence $L_d$ (see Alissandrakis and Gary, 2021 for a review). We evaluate coronal plasma density from local differential emission measure computed from the […]

Discovery of correlated evolution in noise storm source parameters: Insights on $\vec{B}$ dynamics during a microflare
by A. Mohan

2021-04-13 285 views

Solar noise storms are known to be related to small and large scale magnetic field enhancements at active regions (Elgaroy 1977, Li et al.,2017). However, the mechanism still remain unclear. Their high spectro-temporal variability and ubiquity of weak events demanded sub-second and sub-MHz scale imaging with high dynamic ranges (DRs) to reliably study emission from individual sources. Using high DR snapshot spectroscopic images from the Murchison Widefield Array, this work […]

VLA Measurements of Faraday Rotation through a Coronal Mass Ejection Using Multiple Lines of Sight by J. E. Kooi et al.*

2021-02-16 158 views

The Sun is the main source of space weather, and one type of solar event that is critical to space weather is a coronal mass ejection. Coronal mass ejections (CMEs) are large eruptions of magnetized plasma from the Sun that produce energetic particles, which can cause geomagnetic storms on Earth. One method that has proven successful in determining the strength and structure of the coronal magnetic field is Faraday rotation […]

Modulation of radio emission, fast magnetoacoustic waves and magnetic field measurements in the solar corona with LOFAR
by Kolotkov et al*

2018-08-21 615 views

Fast magnetoacoustic wave trains are a promising seismological probe of the corona, revealing the magnetic connectivity and providing the estimation of the absolute value of the coronal magnetic field. Low-frequency radio observations allow for the detection of fast wave trains in middle and upper corona, above the field-of-view of EUV imagers and spectrographs, via the modulation of the radio emission by the variations of the electron concentration. We present the […]

Topical issue “Solar radio physics from the chromosphere to near Earth” published
by E.P Kontar and A. Nindos

2018-06-26 606 views

The 2016 CESRA workshop (http://cesra2016.sciencesconf.org) had a special emphasis on the complementarity of current and future space-based observations with ground-based radio observations. It was the place to discuss the new exciting science opportunities that arise from radio instruments such as the Atacama Large Millimeter/submillimeter Array (ALMA), the Expanded Owens Valley Solar Array (EOVSA), the Expanded Very Large Array (EVLA), the Low Frequency array (LOFAR), the Mingantu Spectral Radioheliograph (MUSER), and […]

Modeling of Solar Atmosphere Parameters Above Sunspots Using RATAN-600 Microwave Observations
by A.G. Stupishin et al.*

2018-05-15 614 views

Models of the upper transition region of sunspots have been derived based on the observed radio spectrum between 3 and 18 GHz from Radio Astronomical Telescope of the Academy of Sciences 600 (RATAN-600) observations. Our objective is to match the spectrum to show that, within the limits of the one-dimensional observations and modeling, we have obtained a reasonable description of the upper transition-region structure of sunspots. We have developed a diagnostic […]

Estimation of a CME magnetic field strength using observations of gyrosynchrotron radiation
by E. P. Carley et al.*

2018-01-09 806 views

Despite many years of study, the dominant driver and energy source of coronal mass ejections (CMEs) is still under investigation. Observational studies have indicated that magnetic energy represents the largest part of the total energy budget of the eruption (Emslie et al., 2012, Carley et al., 2012). However, despite having such a dominant influence on CME dynamics, little is known about CME magnetic field. This is due to the scarcity […]

VLA Measurements of Faraday Rotation through Coronal Mass Ejections
by Jason E. Kooi et al*

2017-11-21 462 views

Coronal mass ejections (CMEs) are large-scale eruptions of ionized gas (or plasma) from the Sun. The ejected material of a CME is associated with strong magnetic fields, which can cause substantial geomagnetic storms at Earth that enhance the radiation space environment and affect global communications and geolocation. Remote-sensing techniques such as Faraday rotation (FR), the rotation of the plane of polarization of linearly polarized radiation as it propagates through a […]

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