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Imaging the solar atmosphere Options for imaging the transition region. Some examples selected for the first QUAFF-Meeting By Udo Schühle Max-Planck-Intitut für Sonnensystemforschung 37191 Katlenburg-Lindau, Germany. Principle design of EUV imager PROBA2/SWAP. Off-axis Ritchey-
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Imaging the solar atmosphereOptions for imaging the transition region Some examples selected for the first QUAFF-Meeting By Udo Schühle Max-Planck-Intitut für Sonnensystemforschung 37191 Katlenburg-Lindau, Germany First Quaff consortium meeting Frankfurt, 9. Dec. 2004
Principle design of EUV imager PROBA2/SWAP Off-axis Ritchey- Chrétien telescope Normal incidence multilayer optics needed Works only below 30nm and above 110 nm First Quaff consortium meeting Frankfurt, 9. Dec. 2004
Options for imaging the transition region Emission spectrum in the VUV measured with SUMER About 500 lines to choose from. But only few suitable for EUV imager First Quaff consortium meeting Frankfurt, 9. Dec. 2004
The „layers“ of the solar atmosphere Spectrally pure imaging - possible only with a spectrograph C I ~15 000 K N V ~180 000 K O VI ~300 000 K First Quaff consortium meeting Frankfurt, 9. Dec. 2004
The Sun in He II and He I: The transition region? SUMER raster: He I 58.4nm EIT: He II 30.4nm First Quaff consortium meeting Frankfurt, 9. Dec. 2004
Close-up look at the network (two SUMER raster scans taken 2 hours apart) Si IV 139.4 nm He I 58.4 nm First Quaff consortium meeting Frankfurt, 9. Dec. 2004
Some images from the transition region Continuum H I Lyman beta C II O VI First Quaff consortium meeting Frankfurt, 9. Dec. 2004
Active regions at the solar limb H I Lyman beta (~15 000 K) and O VI 1037 (~300 000 K) First Quaff consortium meeting Frankfurt, 9. Dec. 2004
Lyman-Alpha image of the VAULT instrument A rocket spectroheliograph using two compensating diffraction gratings Resolution of 0.33“ (per 2 pixels) First Quaff consortium meeting Frankfurt, 9. Dec. 2004
H I Lyman-Alpha Imager H I Lyman Alpha • Is the most important line in the solar spectrum • Has most impact on Earth and heliosphere • It allows to study all features typical of the solar lower atmosphere such as the network, spicules, cold loops, filaments etc. • Has many technical advantages: • Has very high flux • Is spectrally isolated • Filters are commercially available • Mirrors are very efficient (Al+MgF2) First Quaff consortium meeting Frankfurt, 9. Dec. 2004
Lyman-Alpha imager • Advantages: • Simple technology • Efficient filters on MgF2 substrates • Highly efficient mirrors with Al/MgF2 coating • Highly efficient solar blind detectors: I-APS First Quaff consortium meeting Frankfurt, 9. Dec. 2004
Rapid Imaging Spectrograph 1-mirror, 1-grating system First Quaff consortium meeting Frankfurt, 9. Dec. 2004
RAISE intensifier/APS detector configuration (not to scale). Solar-blind intensified APS detector • Advantages: • simple technology • no filter needed for solar-blindness • more efficient than bare APS • choice of photocathode materials • all CMOS-APS sensor capabilities First Quaff consortium meeting Frankfurt, 9. Dec. 2004