1. Flares and Eruptive Events Observed with the XRT on Hinode Kathy Reeves Harvard-Smithsonian Center for Astrophysics

2. Outline 1. Introduction to XRT 2. Some XRT flare observations 3. Temperature analysis of a small flare 4. Modeling XRT flare emission

3. The X-Ray Telescope The XRT is a collaborative effort between SAO (mirror, filters, structure and mechanical systems) and ISAS (camera sensor and electronics). The telescope is a modified Wolter I with a 35 cm aperture and a 2.71 m focal length.

4. New XRT Capabilities Unprecedented combination of field of view and image resolution (pixels 2.5x smaller than SXT) Extremely large dynamic range

5. XRT Temperature Coverage 9 X-ray filters + G-band in focal plane Broadest temperature range coverage of any imager to date

6. AR 0930 - 2 X-flares!

7. Downflows Observed with XRT TRACE 195 XRT med-Be

8. Pre-flare Configuration TRACE 195XRT thin-Be 12/14/2006 10:54 UT

9. Post-flare Configuration TRACE 195XRT thin-Be 12/15/2006 01:33 UT

10. Limb Flare

11. Field Line Shrinkage? Priest & Forbes, A&ARv, 2002

12. Coordinated XRT-SOT Flare Observations

13. Determining Temperatures Useful for understanding location of flare heating, cooling processes in flares and solar eruptions. Method 1 - Filter Ratios Method 2 - Differential Emission Measure Analysis

14. Observations

15. Filter Ratio Analysis

16. Filter Ratios * * *

17. Filter Ratio Analysis

18. DEM Analysis Method developed by M. Weber, E. DeLuca, L. Golub (see L. Golub et al., 2004) DEM determined by a least-squares minimization algorithm Random error generation for determining DEM errors

19. DEM Analysis ambient coronaflare loop

20. DEM Analysis ambient coronaflare loop

21. Emission Measures in Different Temperature Bins 2-3 MK3-5 MK5-10 MK

22. Emission Measures in Different Temperature Bins 10-20 MK20-50 MK50-100 MK

23. Where is the Hot Plasma?

24. RHESSI Data Also useful for constraining DEM: TRACE, EIS, CDS,.....

25. Conclusions so far... Post-flare loops contain multi- thermal plasma, ambient corona is closer to two-temperature plasma Hot plasma is not well determined using this method with only XRT data RHESSI data should be useful in constraining high temperature plasma

26. Model of Solar Eruptions Eruption Model ( Based on Lin & Forbes 2000) Arcade of 1D hydro loops Thermal energy generated here Input here See Reeves & Forbes, ApJ, 2005 Reeves et al., ApJ, submitted

28. Temperatures and Densities Temperature Density

29. Simulated XRT Intensities

30. Some Observations 2006/12/17 C2 flare 2007/01/12 C1.5 flare

31. Loop-top knots may be more than projection effects XRT should see evidence of different conduction fronts in flare plasma Modeling Conclusions

32. Stay tuned for more great XRT flare data as solar maximum approaches...