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Other RHESSI |
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Radio/X-ray observations of flares
 | Variability in time and space of the characteristics of the accelerated particles in the course of flare development. |
| How are particles accelerated ? In which environment ? |
| Multiwavelength studies performed with the Nançay Radioheliograph (NRH) in past version |
| Variation of electron spectra and of e/p ratio on time scales of 10s together with variability in space as seen in radio or Ha . |
Characteristics of the energetic particles and magnetic structures at ¹ scales involved in the flare development using HESSI and new NRH capabilities
2 May 1998 Flare/halo CME
| GOES X disk flare associated with initial stage of a halo CME (Pohjolainen et al…submitted) |
| New radio sources appear during the « flash » phase of the flare (sudden increase of the emission) together with a sudden extension of emission towards high frequencies. |
| Simultaneous jump of HXT source positions at 33-53 keV (sites of non-thermal energy releases). Spectral evolution ? |
| Radio images provide tools to identify the loop systems that participate to the CME |
| Radio images provide tools to understand the effects of EIT/H a waves in destabilizing the coronal field. |
27 November 1997 Flare
| GOES X2 flare associated with production of decimetric/metric type II burst starting at high frequencies ( 400 MHz) |
| Close temporal and spatial relationship between the first signature of the type II burst and the arrival of fast moving plasma blobs at coronal heights (blast wave). ( Klein et al 1999) |
| Earlier flare development |
| X-ray/ g -ray spectral evolution simultaneously with the onset of the shock wave emission ?(to be further checked with OSSE observations) |
| Sudden appearance of a new radio source simultaneously with the sharp X-ray/ g -ray spike and just before the onset of the type II burst… |
| Interpretation … ? |
Nançay Radioheliograph
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| 2d and 2x1d images of the solar corona at 5 to 10 frequencies between 150 and 450 MHz |
| time resolution : 10 im/s (for 5 frequencies) |
| spatial resolution : from 0.6 to 6 arcmin depending on frequency and direction |
| polarization : Stockes I and V |
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observing time : 7.5h around 12h ------------------------------------------------------------------------------------------------------- |
| available on line : http://mesola.obspm.fr |
| data up to one image per 10 seconds |
| + soft in solar soft (NRH branch) |
| next step: direct access in Hessi branch |
| quick look of radio flares associated with HESSI flares? |
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