MultiWavelength Studies of Flare Activities with SolarB ASAI
Multi-Wavelength Studies of Flare Activities with Solar-B ASAI Ayumi Kwasan Observatory, Kyoto University Solar-B Science Meeting @ISAS February 4, 2003
Magnetic Reconnection Model Magnetic Reconnection elemental process for solar flares To solve the mechanism, quantitative studies are needed. Solar-B’s target
Today’s Topic Using various phenomena, we derive the information about the energy release via reconnection. I present the estimation of the energy release rate at flares, by multi-wavelength studies of flares. Analyzed flares • 2000 -April-10 Flare (X 2. 3) • 2002 -July-23 Flare (X 4. 8) • 2000 -November-24 Flare (X 2. 3) Suggestion for the observations with Solar-B
Energy Release Rate Reconnection model indicates Bc : coronal magnetic field strength vin : inflow velocity A : area of the reconnection region Time profiles of HXR and microwave intensities are well fitted with that of d. E/dt I estimate the energy release rate, and compare it with nonthermal light curves.
Data Observational Data Ha・・Kwasan Observatory, Sartorius Telescope EUV・・TRACE (171, 195Å image) magnetogram・・SOHO / MDI hard-X ray・・Yohkoh / HXT RHESSI HXRS (Czech) Sartorius Telescope microwave・・Nobeyama Radioheliograph
2001 -April-10 Flare I ・ April 10, 2001 05: 10 UT ・GOES X 2. 3 class NOAA 9415 East West Ha images taken with Sartorius Telescope
Features of the Flare No. RH Microwave and HXR light curves show some bursts. GOES HXT Sartorius The spatial distributions of Ha kernels are different from those of HXR sources Ha image
Evolution of Flare Ribbons Neutral Line v B I estimate the reconnection rate v×B, and the Poynting flux v×B 2 as the representations of the energy release rates.
Reconnection Rate and Poynting Flux microwave HXR reconnection rate Poynting flux An HXR burst occurred on the slit (05: 19 UT).
Reconnection Rate and Poynting Flux microwave HXR reconnection rate Poynting flux An HXR burst occurred on the slit (05: 26 UT).
Summary I • I have estimated the energy release rate from the separation motions of Ha two ribbons and the photospheric magnetic field strengths. • The estimated reconnection rate and the Poynting flux along each slit show good correlation with nonthermal burst.
2002 -July-23 Flare II ・ July 23, 2002 00: 15 UT ・GOES X 4. 8 class ・NOAA 0039 East West EUV(195Å) images taken with TRACE
Down Flow Time slice image TRACE 195 A The timings of the down flows correspond to microwave/HXR bursts. microwave (No. RH 17 GHz)
2000 -November-24 Flare This flare shows many plasmoid ejections, and each of them is ejected at the time corresponding to the HXR burst. Takasaki (2003) Time slice image Yohkoh/SXT
Summary II • Down flow motions and plasmoid ejections show some correlations with HXR/microwave bursts. Strongly depend on the reconnection process. More quantitative studies are still needed.
Observation with Solar-B • SOT … Ha images with high spatial resolution Magnetograms with high spatial resolution • XRT … Observation of reconnection outflow, and density and temperature of the plasma • EIS … Velocity field of the reconnection outflow • collaboration with other satellite and ground based instruments Hida Obs. , Nobeyama, RHESSI…
- Slides: 16