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Spectral signatures of dynamic plasmas

Spectral signatures of dynamic plasmas. Many space missions over the past 30 yrs A very dynamic Sun. Hinode/SOT. SoHO/EIT. Most data interpreted using the `coronal approximation’ . i.e. Ionization equilibrium assumed, stage-to-stage ionization assumed .. How good is this??? Three examples:

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Spectral signatures of dynamic plasmas

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  1. Spectral signatures of dynamic plasmas • Many space missions over the past 30 yrs • A very dynamic Sun Hinode/SOT SoHO/EIT

  2. Most data interpreted using the `coronal approximation’ . i.e. Ionization equilibrium assumed, stage-to-stage ionization assumed .. How good is this??? Three examples: • Electron density dependent ionization (ii) Transient ionization in the early stages of a solar flare (iii) Non-thermal distributions

  3. Should give the same info???? Consider two resonance lines, N V 1238 ... from Be-like ion O V 629 ... from Li-like ion have over-lapping formation temperatures . SKYLAB data from mid 70’s show O V & N V have a different response, O V QS  AR  3—4 N V QS  AR  8—10 WHY?

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  5. Resolved case .. Metastable included .

  6. N V intensity increases while O V decreases as Ne increases At Ne=1011 cm-3, N V 1238 > 60% .. O V < factor of ~2, thus the response in ARs differ by a factor of ~3

  7. . O V 629/N V 1238 line core ratio At Ne = 1011 cm -3, O V 629 is reduced by almost a factor of two while N V 1238 is increased by almost a factor of two, giving a factor of ~ 3 difference .. would transient ionization make a difference??

  8. .High UV line data from SMM/UVSP show a high correlation with hard X-ray bursts (>25 keV). WHY?

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  10. .correlation of O V 1371 & HXR shows that O V lacks the HXR by 0.3 to 0.7s and is flare dependent

  11. . Converting to the Line Contribution Function, we have a factor of 3 enhancement at 1011 cm-3 after only 0.1s • Response time is prop. to Ne, therefore if Ne is smaller, the response time is longer • Can explain the near simul. UV/HXR response • Need to investigate the possibility of a non-Gaussian Future work: short duration EE seen in TR (105 K) lines but not in Mg X  not important for coronal heating .. BUT we see them Fe XII lines .. WHY .. Transient ionization

  12. . Non-thermal recombination HXR flare date .. Cold thick target (bremsstrahlung) model .. Problem  requires a large # of electrons Recent work suggests nonthermal electrons by recombination is very important  reduced the # of electrons by ~10 .. Problem  they used Kramers approx. Want to use ADAS to look at this problem using better data .. Also, what if we changed from an electron to a proton beam???

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