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P. F. Chen 1,2 , H. Isobe 1 , K. Shibata 1 , A.C. Lanzafame 3 2. Nanjing University, China

On the spectroscopic detection of magnetic reconnection evidence with Solar B – I. Emission line selection and atomic physics issues. P. F. Chen 1,2 , H. Isobe 1 , K. Shibata 1 , A.C. Lanzafame 3 2. Nanjing University, China 3. Catania University, Italy. David H. Brooks.

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P. F. Chen 1,2 , H. Isobe 1 , K. Shibata 1 , A.C. Lanzafame 3 2. Nanjing University, China

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  1. On the spectroscopic detection of magnetic reconnection evidence with Solar B – I. Emission line selection and atomic physics issues P. F. Chen1,2, H. Isobe1, K. Shibata1, A.C. Lanzafame3 2. Nanjing University, China 3. Catania University, Italy David H. Brooks 1. Kwasan Observatory, Kyoto University 京都大学花山天文台 相模原 2月4日

  2. 1.Reconnection evidence from images Expansion and cusp shape of Soft X-ray post-flare loops Above the loop top hard X-ray source Tsuneta et al. （1992) Masuda et al. (1994)

  3. 2.Reconnection evidence from images Reconnection related inflow? Plasmoid ejection Ohyama & Shibata (1998) Yokoyama et al. (2001)

  4. Spectroscopic Observations will: • Remove ambiguity between ‘real’ and ‘apparent’ motions • Allow accurate measurement of plasma flow velocities • Study reconnection physics, reconnection rate etc.

  5. Objectives of this work • Study the signatures in EUV line profiles of plasma flows associated with magnetic reconnection • Determine which lines are best for detecting different flows e.g. reconnection inflow, jet etc. • Determine whether Solar-B can really detect the signatures and what are the best observation targets • 95 spectral lines studied for SERTS DEM analysis (Lanzafame, Brooks, Lang, Summers, Thomas 2002) within Solar-B/EIS wavelength range. • ADAS (Summers 1994) collisional-radiative models including density dependence of ionisation balance* • 2.5D MHD simulations (Chen & Shibata 2000) *Extra. Consider effect of improved atomic data

  6. MHD Simulation 2.5D resistive MHD simulation No heat conduction Flows associated with magnetic reconnection: Inflow: about 1 MK Jet: about 10-30 MK Flux rope: 5000 K-1 MK Coronal Moreton waves: 1-3 MK CME-flare relation Chen & Shibata (2000)

  7. Example: Reconnection Inflow Selecta line within the expected temperature range of the inflow (from simulations) e.g. Fe XII 195.119A formed at 1.6-2MK, and compute line profile along a chosen line of sight Difficult to distinguish inflow emission from expanding flux rope emission Observer Intensity (x 0.9) – Velocity

  8. Intensity map Ex: Inflow Emission Intensity at different velocities Inflow (approx.) < +/- 40 km s-1 Optimise line of sight for detection Observer Red shifted component mainly inflow (30% approx.) I (x 0.9) - v

  9. Ex: Reconnection jet Fe XXIV 192.04A formed at 13-16MK Observer Intensity map I (x 400) - v

  10. Ex: Slow shock pair attached to CME Ca XVII 192.82A formed at 4-5MK Observer Intensity map I (x 15) - v

  11. Result: Classification of 95 lines Classification codes: I - Inflow, S - Shock, J - Jet, M - coronal Moreton wave

  12. Crude approx. of effect of simulation Te Fe XII 195 logT=6.15 Fe XV 284 logT=6.3 S XIII 256 logT=6.4 • Heat conduction will change simulation temperaturesand affect choice of lines

  13. Preliminary selection of emission lines – dependent on this model Inflow coronal Moreton wave slow shocks jet

  14. Density dependence of Fe IX 171.073A Solid line – 104 cm-3 Dashed Line –1011 cm-3 factor 3 Log scale G(Te,Ne) function Line Profile Inaccurate treatment of density sensitivity of G (Te, Ne) function leads to incorrect prediction of strong inflow for this line!

  15. Summary • Using Chen & Shibata (2000) MHD simulations and • ADAS data we have simulated the profiles of 95 • spectral lines which will be observed by EIS • Examined signatures of reconnection inflow, jet, slow • shock attached to expanding CME, coronal Moreton • wave • Classified 95 lines: guide for planning observations & • line selection. Preliminary recommendation: Fe XV • 195A (inflow), Fe XXIV 192A (jet), etc. • Some line profile shapes may be altered as a result of • including density sensitivity of ionisation balance: • could lead to criticism of reconnection model if strong • flows are not detected

  16. Future work Results based on these specific simulations so: 1. Parameter survey 2. Larger range of electron densities 3. Effect on classifications 4. Include heat conduction Lines of sight etc. in the ideal case so: 1. Consider whether EIS can really observe the inflows given the instrumental characteristics 2. Consider best targets to detect evidence (Isobe)

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