Statistical Analysis of Acoustic Wave Power and Flows around Solar Active Regions

AbstractIn the last decades, numerous observational and computational studies have shown that the global flare distribution is a power-law with a slope less than 2. In these studies, active regions are treated as statistically indistinguishable. To test this, we identify and separately analyze the flares produced by ten individual active regions (2006-2016). In five regions, we find a single power-law distribution, with a slope of a < 2. In the other five, we find a broken double power-law distribution, with slopes a1 < 2 and a2 > 2.

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Solar active regions: a nonparametric statistical analysis

Astronomy and Astrophysics ◽

10.1051/0004-6361/200913193 ◽

2010 ◽

Vol 513 ◽

pp. A48 ◽

Cited By ~ 8

Author(s):

J. Pelt ◽

M. J. Korpi ◽

I. Tuominen

Keyword(s):

Statistical Analysis ◽

Active Regions ◽

Solar Active Regions ◽

Nonparametric Statistical

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The results of statistical analysis of the coronal profiles above the solar active regions

Solar Physics ◽

10.1007/bf00146429 ◽

1977 ◽

Vol 54 (1) ◽

pp. 135-138 ◽

Cited By ~ 1

Author(s):

E. I. Tetruashvili

Keyword(s):

Statistical Analysis ◽

Active Regions ◽

Solar Active Regions

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Radio Measurements of Coronal Magnetic Fields

International Astronomical Union Colloquium ◽

10.1017/s0252921100024933 ◽

1994 ◽

Vol 144 ◽

pp. 21-28 ◽

Cited By ~ 4

Author(s):

G. B. Gelfreikh

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Solar Corona ◽

Active Regions ◽

High Sensitivity ◽

Coronal Magnetic Field ◽

Transverse Magnetic ◽

Radio Sources ◽

Radio Waves ◽

Solar Active Regions

AbstractA review of methods of measuring magnetic fields in the solar corona using spectral-polarization observations at microwaves with high spatial resolution is presented. The methods are based on the theory of thermal bremsstrahlung, thermal cyclotron emission, propagation of radio waves in quasi-transverse magnetic field and Faraday rotation of the plane of polarization. The most explicit program of measurements of magnetic fields in the atmosphere of solar active regions has been carried out using radio observations performed on the large reflector radio telescope of the Russian Academy of Sciences — RATAN-600. This proved possible due to good wavelength coverage, multichannel spectrographs observations and high sensitivity to polarization of the instrument. Besides direct measurements of the strength of the magnetic fields in some cases the peculiar parameters of radio sources, such as very steep spectra and high brightness temperatures provide some information on a very complicated local structure of the coronal magnetic field. Of special interest are the results found from combined RATAN-600 and large antennas of aperture synthesis (VLA and WSRT), the latter giving more detailed information on twodimensional structure of radio sources. The bulk of the data obtained allows us to investigate themagnetospheresof the solar active regions as the space in the solar corona where the structures and physical processes are controlled both by the photospheric/underphotospheric currents and surrounding “quiet” corona.

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