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At line 207 changed 2 lines
*11:30 Tetsuya Watanabe
Correlation of Doppler speed and non-thermal width implies unresolved flows in acrive regions.
!11:30 Tetsuya Watanabe
* Correlation of Doppler speed and non-thermal width implies unresolved flows in acrive regions.
At line 210 changed 2 lines
Recent results from DHB: even if we look at 1 arcsec pixel of Quiet Sun, we usually have the same shape of EM distributions. Unresolved very common nature of a plasma temperature distribution that causes this universal shape of DEM even in a size less than 1".
Triggered by Sakao et al.'s observations, we observe high-velocity outflows, although they're slow in the solar wind sense. We've actually found plasma upflows taking place close to coronal holes and quiet Sun beside active regions. The same sort of mechanism took place the data analysed by Imada after the largest 20061213 flare. In quiet regions, the kinetic energy is roughly enough to heat the QS corona.
* Recent results from DHB: even if we look at 1 arcsec pixel of Quiet Sun, we usually have the same shape of EM distributions. Unresolved very common nature of a plasma temperature distribution that causes this universal shape of DEM even in a size less than 1".
* Triggered by Sakao et al.'s observations, we observe high-velocity outflows, although they're slow in the solar wind sense. We've actually found plasma upflows taking place close to coronal holes and quiet Sun beside active regions. The same sort of mechanism took place the data analysed by Imada after the largest 20061213 flare. In quiet regions, the kinetic energy is roughly enough to heat the QS corona.
At line 213 changed 2 lines
20061217 LDE was analysed by Hara: Reconnection inflows seen in LOS velocity by HH;
20060519 flare: EIS counterpart of a ''Masuda'' source? The EIS slit was very lucily at the flaring loop top when its initial phase started. ''TRACE'' shows a clear two-ribbon pattern; RHESSI image contours for 12 - 25 keV which show a high-temperature RHESSI structure. Fe XXIII emission corresponding to it shows a slight red-shift.
* 20061217 LDE was analysed by Hara: Reconnection inflows seen in LOS velocity by HH;
* 20060519 flare: EIS counterpart of a ''Masuda'' source? The EIS slit was very lucily at the flaring loop top when its initial phase started. ''TRACE'' shows a clear two-ribbon pattern; RHESSI image contours for 12 - 25 keV which show a high-temperature RHESSI structure. Fe XXIII emission corresponding to it shows a slight red-shift.
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* 20061213 flare seems to show a fast-mode shock propagation, seen by Asai et al. This shock propagates close to the Alfven velocity in the quiet solar corona.
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* 20070606 Chromosphere evaporation. at the beginning, no blueshift in Fe XXIII. But blueshifts seen in all four footpoints of the flaring loops. In the final image where you see loop in Fe XXIII, the position of the high-temperature line is moving back to rest. So we actually see very dynamic and violent chr'c evaporation in this event. Plasma evaporation has a very fine structure, too. In this particular flare (20070116),we just observe the middle of a C flare (post-impulsive phase). Even then, the line profile of Fe XXIII is diferent from one location to the next. The blue-shift itself is not so strong, but the entire line width is much larger in one place. Wile in Fe XV, the bottom line shows a down-flow in certain parts of a flaring loop. So the plasma motions are very complicated, of course depending on the phase of the flare, but it also depends on whether we're seeing elementary loops; that part is beyond our resolution, though.
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*11:50 Louise Harra
*12:10 George Doschek
* Diagnostics:
** EIS can observe emission lines from Fe VIII to Fe XXIV! So without relative abundance uncertainties, we can make ionsiation temperature diagnostics from log T = 5.6 to 7.3.
Thanks to the high resolution of the EIS grating, we detected a huge number of Fe lines with various ionisation species, much less blended than in spectra taken ever before.
E.g, Fe XIII in the short wavelength band. TW showed the EIS spectrum versus a lab spectrum taken by the National Institute for Fusion Sciences, but the latter's spectrograph isn't as good as an orbital spectrograph(!). Due to this high spectral resolution, EIS spectra are used to check data for the high-density limit.
** High-T lines: Warren et al.; Patsourakos & Klimchuk (2006)
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TJ Wang commented that the Sakao flows may be waves already seen with TRACE.
!11:50 Louise Harra
* Reconnection Jets: Kamio
* Enhanced non-thermal broadenings at footpoints: Hara; evidence of nano-flare heating?
* Turbulence is stronger outside the bright loops: Doschek; possibly consistent with some kind of wave-generated heating?
* Oscillations within a loop: Mariska; temperature dependence of decay times with temperature (Fe stage)
* Wide range of oscillations in different parts of active regions: O'Shea & Doyle
Transient phenomena
* have observed mass motions in all transient phenomena
* are also observing pre-event phenomena
* Energy transfer: work is beginning but there needs to be a lot more cross-connection with SOT.
* Can now observe the region where reconnection may be observing
* Tripathi & Kliem: looking at where flux ropes may be formed: Fe XV emission takes the form of two J-shapes, but the cooler emission in Fe XII takes an S-shape form, which lies along the inversion line, and they measure flux cancellation there. This, and work by Green et al. shows rope forming gradually rather than being formed frombelow the surface.
* Sakao, Marsch, Del Zanna, Doschek all did work on outflows
** If you do the force-free extrapolation, you get open or highly-extended field lines where the outflows seem to be coming from
** Baker & Mandrini did work on where the QSLs might be and found them to be in regions of outflows. Seems to suggest that magnetic reconnection seems to drive the outflows. What this does do is not necessarily say that waves aren't there, but that the source of them is where the QSLs are. Reconnection is taking place and waves are formed, but the key thing is that it's happening at the QSLs.
*CMEs: 20061214, there was a loss of plasma; the source region of the CME is seen; can now understand the morphology of dimming regions in ways we couldn't before. van Driel is looking CME expansion into the solar wind. Loop-like dimmings show persistent brightenings(?)
** Imada showed temperature-dependent outflow.
So we
* Upflows in ARs. We know they're persistently seen at the edges of ARs. Showed one beside a coronal hole. There's an intensification of the upflows about 4 or 5 hours before a CME. even for smaller events, can see pre-event signatures.
Last goal is energy transfer from the photosphere to the corona.
* Murray: signatures of active region expansion: AR in a coronal hole. There's a pressure gradient that accelerates the plasma vertically.
* Brooks: transient brightenings: transient brightenings in areas of flux collision, not in areas connected to hot loops.
Things we need to do:
# Find out what lies above the kG fields in CHs
# Find reconnection inflow
# Relate different oscillations to the magnetic environment
# Link outflows in ARs to solar wind measured by STEREO/HI and ACE
# Find other examples of shock waves and understand their relation with temperature
!12:10 George Doschek
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This page (revision-83) was last changed on 02-Feb-2017 13:19 by David R WilliamsTop