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

KAUFMANN, P.; TROTTET, G.; GIMENEZ DE CASTRO, C; RAULIN, J.P.; GARY, D.; FERNANDEZ G.; GODOY, R.; LEVATO H.; MARUN, A.; PEREYRA, P.

Honolulu, Hawai

Congreso; American Astronomical Society Meeting; 2007

American Astronomical Society

The solar burst spectral component peaking somewhere in the terahertz (THz) range, along with,but distinct from, the well-known microwave component, bring new observational and theoreticalpossibilities to explore the flaring physical processes. The solar event of December 6, 2006, 18:30 UT,exhibited a particularly well-defined double spectral structure, with the THz spectral component detected at212 and 405 GHz by SST and microwaves (1-18 GHz) by OVSA. The burst was observed by instruments insatellites at high energies, UV by TRACE, soft X-rays by GOES, X- to γ- rays by RHESSI. Although theevent occupied an extended area at optical and UV wavelengths, showing various brightnings along severalarcminutes, the hard X-ray emission region is restricted (within a region ~30” x 50”) showing three sourcesat low energies (< 150 keV) and a single source above 300 keV. At submillimeter-waves, a precursor wasobserved, followed by a rapid impulsive event and a post-burst long-enduring component. This post-burstcomponent was also accompanied by the largest flux-density decimeter burst ever reported, reaching 1million solar flux units. The submillimeter impulsive burst centroid position at 212 GHz was clearlydisplaced from the precursor component by almost 1 arc-minute. The maximum limit sizes, estimated at 212GHz, were of the order or smaller than the beam-sizes (4’). The microwave spectra for the precursor andlong-enduring burst components peak at about 5-10 GHz. The submillimeter precursor spectrum might beoptically thick emission of the cold chromospheric plasma. Despite the complexity in space, time andspectra of the superimposed impulsive and post-impulsive emission, it was remarkable that the THzimpulsive component had its closer counterpart only in the higher energy X- and γ- rays ranges, suggestingthat they are part of the same physical process, produced by a source of continuously acceleratedhigh-energy particles.