Solar Burst Submillimeter Wave Emission Components Associated To Microwaves, UV, X- And Gamma- Rays Continuum In Time And Space

P.KAUFMANN; G. TROTTET; C. G. GIMÉNEZ DE CASTRO; J-P. RAULIN; DALE E. GARY; G. FERNANDEZ; R. GODOY; H. LEVATO; A. MARUN; P. PEREYRA

Honolulu, Hawai

Congreso; American Astronomical Society Meeting 210; 2007

American Astronomical Society

The presence of a solar burst spectral component peaking somewhere in the terahertz (THz) range, along with, but distinct from, the well-known microwave spectral component, bring new possibilities to explore the flaring physical processes, both observational and theoretical. The solar event of December 6, 2006, starting at about 18:30 UT, exhibited a particularly well-defined double spectral structure, with the THz spectral component detected at 212 and 405 GHz by SST and microwaves (118 GHz) observed by OVSA. The burst was observed by instruments in satellites at high energies, UV by TRACE, soft X-rays by GOES, X-to gamma-rays by RHESSI. Although the event occupied a rather extended area at optical and UV wavelengths, showing various brightnings extending along several arcminutes, the hard X-ray emission region is more restricted (contained within a region 30" x 50") and shows three sources at low energies (< 150 keV) and a single source above 300 keV. At submillimeter-waves, a precursor was observed, followed by a rapid impulsive event and a post-burst long-enduring component. This post-burst component was also accompanied by the largest flux-density decimeter burst ever reported, reaching 1 million solar flux units. The submillimeter impulsive burst centroid position at 212 GHz was clearly displaced from the precursor component by almost 1 arc-minute. The maximum limit sizes, estimated at 212 GHz, were of the order or smaller than the beam-sizes (4?). The microwave spectra for the precursor and long-enduring burst components peak at about 5-10 GHz. The submillimeter precursor spectrum might be optically thick emission of the cold chromospheric plasma. Despite the complexity in space, time and spectra of the superimposed impulsive and post-impulsive emission, it was remarkable that the THz impulsive component had its closer counterpart only in the higher energy X-and gamma-rays ranges, suggesting that they are part of the same physical process, produced by a source of continuously accelerated high-energy particles.