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arXiv · 0811.3488

Sub-terahertz, microwaves and high energy emissions during the December 6, 2006 flare, at 18:40 UT

Pierre Kaufmann·Gerard Trottet·C. Guillermo Gimenez de Castro·Jean-Pierre Raulin·Sam Krucker·Albert Y. Shih·Hugo Levato
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Abstract

The presence of a solar burst spectral component with flux density increasing with frequency in the sub-terahertz range, spectrally separated from the well-known microwave spectral component, bring new possibilities to explore the flaring physical processes, both observational and theoretical. The solar event of 6 December 2006, starting at about 18:30 UT, exhibited a particularly well-defined double spectral structure, with the sub-THz spectral component detected at 212 and 405 GHz by SST and microwaves (1-18 GHz) observed by the Owens Valley Solar Array (OVSA). Emissions obtained by instruments in satellites are discussed with emphasis to ultra-violet (UV) obtained by the Transition Region And Coronal Explorer (TRACE), soft X-rays from the Geostationary Operational Environmental Satellites (GOES) and X- and gamma-rays from the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). The sub-THz impulsive component had its closer temporal counterpart only in the higher energy X- and gamma-rays ranges. The spatial positions of the centers of emission at 212 GHz for the first flux enhancement were clearly displaced by more than one arc-minute from positions at the following phases. The observed sub-THz fluxes and burst source plasma parameters were found difficult to be reconciled to a purely thermal emission component. We discuss possible mechanisms to explain the double spectral components at microwaves and in the THz ranges.

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Pierre Kaufmann, Gerard Trottet, C. Guillermo Gimenez de Castro, Jean-Pierre Raulin, Sam Krucker, Albert Y. Shih, Hugo Levato. 2008-12-17. Sub-terahertz, microwaves and high energy emissions during the December 6, 2006 flare, at 18:40 UT. https://doi.org/10.1007/s11207-008-9312-7

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