천문학회지 (Journal of The Korean Astronomical Society)

한국천문학회 (The Korean Astronomical Society)
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SOLAR ACTIVE REGION STUDY USING MICROWAVE MAPS

  • BONG SU-CRAN (Astronomy Program, SEES, Seoul National University) ;
  • LEE JEONGWOO (Department of Physics, New Jersey Institute of Technology) ;
  • GARY DALE E. (Department of Physics, New Jersey Institute of Technology) ;
  • YUN HONG SIK (Astronomy Program, SEES, Seoul National University)
  • 발행 : 2003.06.01
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초록

Quiescent solar radiation, at microwave spectral regime, is dominated by gyroresonant and thermal Bremsstrahlung radiations from hot electrons residing in solar active region corona. These radiations are known to provide excellent diagnostics on the coronal temperature, density, and magnetic field, provided that spatially resolved spectra are available from observations. In this paper we present an imaging spectroscopy implemented for a bipolar active region, AR 7912, using the multifrequency interferometric data from the Owens Valley Solar Array (OVSA), as processed with a new imaging technique, so-called Spatio-Spectral Maximum Entropy Method (SSMEM). From the microwave maps at 26 frequencies in the range of 1.2-12.4 GHz at both right- and left-circular polarizations, we construct spatially resolved brightness spectra in every reconstructed pixel of about 2 arcsec interval. These spectra allowed us to determine 2-D distribution of electron temperature, magnetic field of coronal base, and emission measure at the coronal base above the active region. We briefly compare the present result with existing studies of the coronal active regions.

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참고문헌

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피인용 문헌

  1. Sunspots at centimeter wavelengths vol.6, pp.S273, 2010, https://doi.org/10.1017/S1743921311015353
  2. Radio Emissions from Solar Active Regions vol.133, pp.1-4, 2007, https://doi.org/10.1007/s11214-007-9206-2