1. IMAGING AND SPECTOROPIC INVESTIGATIONS OF A SOLAR CORONAL WAVE: PROPERTIES OF THE WAVE FRONT AND ASSOCIATED ERUPTING MATERIAL L OUISE K. HARRA AND A LPHONSE C. STERLING ApJ 2003, 587, 429 – 438 太陽雑誌会 発表日時 ： 平成 15 年 4 月 14 日

2. 2 ABSTRUCT

3. 3 INTRODUCTION observed with SOHO/EIT. appear as roughly circular propagating features. appear as a bright front. a few hundred km/s. TRACE also observed (Wills-Davey & Thompson, 1999) 1 EIT wave – coronal wave

4. 4 INTRODUCTION flare-related phenomena seen in the chromosphere (H  ) (Moreton 1961). propagate at a speed of about 1000 km/s. identified as the footpoints of a fast-mode wave in the corona (Uchida 1968). 1 Moreton wave

5. 5 Uchida model (1968) shock front Moreton wave ?? wave, coronal counterpart of Moreton wave flare site solar disk

6. 6 INTRODUCTION Warmuth et al., 2001  Moreton wave and coronal wave are cospatial, and decelerate. 1 H  Moreton wave & EIT coronal wave Eto et al., 2002  Moreton wave differs physically from coronal wave. – speed and location

7. 7 INTRODUCTION CME – Coronal Mass Ejection  filament material typically trailing behind a main CME front. CME & EIT coronal wave  Sharp, well-defined coronal waves are always associated with flare and CMEs, and Moreton waves are frequently observed in these case. 1 CME & EIT coronal wave

8. 8 INTRODUCTION In this paper, we attempt to improve our understanding of coronal waves and their relation to eruptions by observing an event on the solar disk using EUV imaging and spectral observations. 1

9. 9 INSTURUMENTATION TRACE  cadence : 1~2 sec  wavelength 195 Å (half-resolution) 171 Å (full-resolution) 1216 Å (half-resolution) SOHO/EIT  wavelength 195 Å – wave and dimming 304 Å – filaments SOHO/CDS  raster time : 5 minutes  field of view : 102” × 240”  7 wave bands 2

10. 10 OBSERVATIONS AND DATA ANALYSIS 3 1998/06/13 15:00UT AR 8237 C2.9 EIT 195 image TRACE CDS

11. 11 OBSERVATIONS AND DATA ANALYSIS 3 3.1. Coronal Wave – TRACE 195 Å percentage difference image : (image – 15:25:52 image) / 15:25:52 image CDS

12. 12 OBSERVATIONS AND DATA ANALYSIS 3 3.1. Coronal Wave percentage difference image : (image – 15:25:52 image) / 15:25:52 image “bright wave” : 200 km/s “weak wave” : 500 km/s “weak wave”  interacts with a set of loops (TRACE) : loop oscillation  line-of-sight motion (CDS) : no substantial line shifts  less than 10 km/s

13. 13 OBSERVATIONS AND DATA ANALYSIS 3 3.2. Expelled Material – O V (629.75 Å ) vel2 vel1 2 components vel1: either nearly stationary or relatively weakly blueshifted. vel2: much more strongly blueshifted.

14. 14 OBSERVATIONS AND DATA ANALYSIS vel1  blueshift : 150 km/s  velocity : stay  observed in only O V vel2  blueshift : 350 km/s  velocity : 200 km/s  observed in other emission lines 3 3.2. Expelled Material – O V (629.75 Å ) transition region Log T = 5.4

15. 15 OBSERVATIONS AND DATA ANALYSIS vel2 Mg X : corona O V : transition region He I : cool  cover a wide temperature range propagation velocity : 150 ~ 270 km/s 3 3.2. Expelled Material – blueshift 300 km/s

16. 16 OBSERVATIONS AND DATA ANALYSIS 3 3.2. Expelled Material – blueshifted O V & filament Blueshifted O V = vel2 surge or filament-like feature, with a portion of the feature braking off from another (southern) portion that remains attached to the SUN. This braking up of the ejected feature could be responsible for the two velocity components, val1 and vel2.

17. 17 OBSERVATIONS AND DATA ANALYSIS 3 3.2. Expelled Material – blueshifted O V & filament val1 stay val2 200 km/s filament

18. 18 OBSERVATIONS AND DATA ANALYSIS 3 3.2. Expelled Material – blueshifted O V & filament

19. 19 DISCUSSION coronal wave consists of two features (or aspects)  bright wave : roughly circular wave front  break up  weak wave : appears to form from dispersion of the bright wave. 4 coronal wave observed with TRACE

20. 20 DISCUSSION 4 coronal wave  weak wave : line-of-sight velocity : less than about 10 km/s dimming result from CME material being expelled away from the SUN (Harra & Sterling, 2001). coronal wave observed with CDS

21. 21 DISCUSSION Uchida et al., 2001 : EIT coronal waves are due to secondary ling-wavelength first- mode waves that have a lower propagation velocity than Moreton wave. Chen et al., 2002 :  Moreton wave : piston-driven shock  EIT wave : the opening of the field lines associated with an erupting flux rope. 4 numerical simulation

22. 22 DISCUSSION line-of-sight velocity  observation : > 10 km/s  simulation : much faster timing of ejected filament material  observation : several minutes after the passage of the coronal wave  simulation : There can be a large set of overlying magnetic fields, which drive the coronal wave, above the filament.  consistent 4 Chen’s simulation & observation

23. 23 Moreton wave おまけ timing of ejected filament material

24. 24 MHD shock theory (Priest, 1982) BEHINDAHEAD Shock front Using Eq. (1)-(7), the quantities ahead of the shock (I X1,T 1,B 1,θ 1,v 1 ) determine those behind (I X2,T 2,B 2,θ 2,v 2 ). I X1 T 1 B 1 θ 1 v 1 I X2 T 2 B 2 θ 2 v 2 I X1 T 1 B 1 θ 1 v 1 I X2 T 2 B 2 θ 2 v 2 おまけ Narukage’s estimation of line-of-sight velocity

25. 25 Prediction From my analysis, we can estimate the coronal plasma velocity just behind the Moreton wave (fast-mode MHD shock), v 1 -v 2, to be about 100~200 km/s, which would be observed at 50~100 km/s along the line-of-sight with SOHO / CDS or Solar B / EIS. BEHINDAHEAD おまけ Narukage’s estimation of line-of-sight velocity

26. 26 DISCUSSION 4 observed ejection at cool (He I ), transition region (O V ), and coronal (Mg X ) temperature.  cool filament material being ejected together with hotter surrounding material.  There are probably two physical parts.  < 300 km/s : violently thrown out from the SUN  150 km/s : either leaves more slowly or end up not leaving the SUN Ejected filament-like material

27. 27 DISCUSSION 4 The Solar-B satellite will have the potential to carry out this type of analysis more regularly.  EUV Imaging Spectrometer (EIS) 2 km/s Doppler velocity resolution FOV : 6’ x 8’ spatial resolution : 1” in the future

28. END Thank you very much for your attention.