TRACE http vestige lmsal com Imaging Solar Coronal

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TRACE: http: //vestige. lmsal. com Imaging Solar Coronal Structure With TRACE Leon Golub, SAO

TRACE: http: //vestige. lmsal. com Imaging Solar Coronal Structure With TRACE Leon Golub, SAO ISAS - 4 Feb. 2003

http: //hea-www. harvard. edu/SSXG/ The SAO Solar-Stellar X-ray Group • Leon Golub • •

http: //hea-www. harvard. edu/SSXG/ The SAO Solar-Stellar X-ray Group • Leon Golub • • • Jay Bookbinder Ed De. Luca Mark Weber Joe Boyd Paul Hamilton Dan Seaton • With results from A. Van Ballegooijen, A. Winebarger and H. Warren

The Major Coronal Physics Problems 1. Why is the corona hot? 2. Why is

The Major Coronal Physics Problems 1. Why is the corona hot? 2. Why is the corona structured? 3. Why is the corona dynamic & unstable? Emergence of B into the atmosphere, and response to B.

Why Use X-rays to Observe Corona?

Why Use X-rays to Observe Corona?

Heating & Dynamics in ARs TRACE sees four (or possibly only three) distinct processes

Heating & Dynamics in ARs TRACE sees four (or possibly only three) distinct processes in active regions: 1. Steady outflows in long, cool structures. ◄ 2. Transient loop brightenings in emerging flux areas. Also hot & cool material intertwined – May or may not be related to TLBs. 3. Steady heating of hot loops (moss). ◄ 4. Flare-like events at QSLs (or may be cooling events predicted by 3. ).

Examples of all four phenomena

Examples of all four phenomena

Another example of flows

Another example of flows

TRACE Active Region Observations are not Consistent With Hydrostatic Model Figure from Aschwanden et

TRACE Active Region Observations are not Consistent With Hydrostatic Model Figure from Aschwanden et al. 2000 11

Non-HS Loops are ubiquitous 12 courtesy H. Warren

Non-HS Loops are ubiquitous 12 courtesy H. Warren

Partial Listing of Recent Papers About Non-Hydrostatic Loops • • Lenz etal 1999, Ap.

Partial Listing of Recent Papers About Non-Hydrostatic Loops • • Lenz etal 1999, Ap. J, 517, L 155. • Aschwanden etal 2000, Ap. J, 531, • 1129. • Winebarger etal 2001, Ap. J, 553, • L 81. • • Schmelz etal 2001, Ap. J, 556, 896. • • Chae etal 2002, Ap. J, 567, L 159. • • Testa etal 2002. Ap. J, 580, in press. • Martens etal 2002, Ap. J, 577, L 115. • • Schmelz 2002, Ap. J, 578, L 161. • Aschwanden 2002 , Ap. J, 580, L 79. • • Warren etal 2003, Ap. J, submitted. • • Small gradient in filter ratio, high n. Multithread model (a la Peres etal 1994, Ap. J 422, 412), footpoint heating. Flows and transient events in non-hydrostatic loops. DEM spread → const. filter ratio. More passbands may help. Large range in thread T for some loops. Full DEM need at each point. Grad T along loops w/flat filter ratio Contra Martens. Repeated heating episodes.

What Needs to be Explained? • 1. 195 A/173 A ratio is flat. •

What Needs to be Explained? • 1. 195 A/173 A ratio is flat. • 2. Emission extends too high for hydrostatic loop (this is debated, though). • 3. Loop density is high by an order of magnitude. • 4. Apparent flows (and some Doppler shifts measured).

Active Region 8536

Active Region 8536

How isothermal are these loops?

How isothermal are these loops?

SUMER Velocities 17

SUMER Velocities 17

Symmetric vs. Asymmetric Heating

Symmetric vs. Asymmetric Heating

Winebarger etal Ap. JL (2001) Static vs. Flow Model

Winebarger etal Ap. JL (2001) Static vs. Flow Model

High-Conductance Model with Asymmetric Heating

High-Conductance Model with Asymmetric Heating

The Effect of High Conductivity

The Effect of High Conductivity

Footpoints in Transient Heating 1. Initial energy release along current sheet (“spotty”) 2. Footpooint

Footpoints in Transient Heating 1. Initial energy release along current sheet (“spotty”) 2. Footpooint brightening. 3. Evaporation, then post-flare loops.

Comparison: Evaporative Model vs. TRACE Obs.

Comparison: Evaporative Model vs. TRACE Obs.

Moss as TR of Hot Loops

Moss as TR of Hot Loops

Heating Shut-off vs. Observations

Heating Shut-off vs. Observations

Hot Material in the Corona Mg XII Ly-α superposed on Fe X (log T

Hot Material in the Corona Mg XII Ly-α superposed on Fe X (log T = 6. 9 and 6. 0) Consistent with RHESSI detection of non-thermal electrons in “quiescent” active regions.

END PRESENTATION

END PRESENTATION

Warren & Warshall, Ap. JL (2001) March 17, 2000 M 1. 1: TRACE 1600

Warren & Warshall, Ap. JL (2001) March 17, 2000 M 1. 1: TRACE 1600 Å Movie

March 17, 2000 M 1. 1: TRACE 1600 Å Images

March 17, 2000 M 1. 1: TRACE 1600 Å Images

March 17, 2000 M 1. 1: TRACE 1600 Å Light Curves

March 17, 2000 M 1. 1: TRACE 1600 Å Light Curves

TRACE Footpoint vs. BATSE HXR →HESSI!

TRACE Footpoint vs. BATSE HXR →HESSI!

The Solar-B Mission

The Solar-B Mission

The Solar-B Instrument Complement 1. Solar Optical Telescope with Focal Plane Package (FPP) -

The Solar-B Instrument Complement 1. Solar Optical Telescope with Focal Plane Package (FPP) - 0. 5 m Cassegrain, 480 -650 nm - VMG, Spectrograph - FOV 164 X 164 arcsec 2. EUV Imaging Spectrograph (EIS) - Stigmatic, 180 -204, 240 -290Å - FOV 6. 0 X 8. 5 arcmin 3. X-ray Telescope (XRT) - 2 -60Å - 1 arcsec pixel - FOV 34 X 34 arcmin

XRT vs. SXT Comparison 1. Higher spatial resolution: 1. 0” vs. 2. 5” 2.

XRT vs. SXT Comparison 1. Higher spatial resolution: 1. 0” vs. 2. 5” 2. Higher data rate: 512 k. B continuous. 3. Ten focal plane analysis filters. 4. Extended low-T and high-T response. 5. FIFO buffer for flare-mode obs.

Science Themes • • Plasma Dynamics Thermal Structure and Stability The Onset of Large

Science Themes • • Plasma Dynamics Thermal Structure and Stability The Onset of Large Scale Instabilities Non-Solar Objects 65

Plasma Dynamics • Reconnection – – – loop-loop interaction flux emergence nano-flares AR jets

Plasma Dynamics • Reconnection – – – loop-loop interaction flux emergence nano-flares AR jets macro-spicular jets filament eruption 66

Plasma Dynamics • Waves – origin of high speed wind – tube waves –

Plasma Dynamics • Waves – origin of high speed wind – tube waves – coronal seismology Figures from Nakariakov et al. (1999): decaying loop oscillations seen in TRACE can be used to estimate the coronal dissipation coefficient. Re ~ 6 x 105 or Rm ~ 3 x 105 , about 8 orders of magnitude less than classical values. 67

Thermal Structure/Stability • Physical Properties – Te, ne, EM – energetics – variability timescales

Thermal Structure/Stability • Physical Properties – Te, ne, EM – energetics – variability timescales • Multithermal Structure – steady loops – filaments 68

Onset of Large Scale Instabilities • Emerging Flux Region – twisting/untwisting – reconnection •

Onset of Large Scale Instabilities • Emerging Flux Region – twisting/untwisting – reconnection • delta Spots – current sheets – topology changes • Active Filaments – T e , ne – local heating 69

Non-Solar Objects • Jupiter – S VII @ 198 • Nearby RS Cvns •

Non-Solar Objects • Jupiter – S VII @ 198 • Nearby RS Cvns • Galaxy Cluster Halos • Comets • Any EUVE source within 1 deg of Sun 70

Science Drivers I: Spatial Scales • “Global” MHD Scales – Active Regions; – granulation

Science Drivers I: Spatial Scales • “Global” MHD Scales – Active Regions; – granulation scales • Transverse scales - d. T, dn - d. B^ and j • Reconnection sites – location – size – dynamics 105 km 103 km 101 - 103 km <10 km RAM discovery space <10 km

Science Drivers II: Time Scales • Loop Alfven time • Sound speed vs. loop

Science Drivers II: Time Scales • Loop Alfven time • Sound speed vs. loop length • Ion formation times • Plasma instability times • Transverse motions • Surface B evolution times • ~100 sec • ~1 - 10 sec • ~10 - 100 sec • 1 - 100 sec • minutes - months

Optics Metric

Optics Metric