By Dr. Gordon Hurford,
Senior scientist of Space Sciences Laboratory, UC-Berkeley, USA
Abstract: This talk begins with a review of the role of x-ray and radio observations in studying magnetic reconnection and particle acceleration processes in solar flares. Recent RHESSI results are presented to illustrate insights that can be obtained from high-resolution x-ray and gamma-ray imaging spectroscopy. These results include imaging of solar emission from narrow gamma-ray lines produced by accelerated nuclei, x-ray estimates of the location, size and ambient density of the acceleration region and new observations of long-lived coronal gamma-ray sources produced by electron bremsstrahlung.
An alternate perspective on flare-accelerated electrons is provided by observations at radio wavelengths. Microwave imaging spectroscopy can also provide quantitative diagnostics of the accelerated electrons as well as direct measurements of the magnetic fields on which they propagate. Decimetric imaging spectroscopy promises to provide a quasi 3-dimensional view of accelerated electrons in the solar corona. To provide these insights, however, requires imaging spectroscopy over wide frequency ranges, as will be achieved with the Chinese Spectral Radio Heliograph and a proposed Frequency-Agile Radio Interferometer.
Time: 2009-3-19, 14:00
Place: Room A601
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