München 2019 – wissenschaftliches Programm
EP 9.23: Poster
Donnerstag, 21. März 2019, 16:30–19:00, Durchgangshalle
A linear slit coronagraph combined with a high resolution partailly multiplexed imaging spectrometer — •Adalbert M. Ding1 and Shadia R. Habbal2 — 1Institut für Technische Physik, Berlin, and IOAP, Technische Universität Berlin — 2Institute for Astronomy, University of Hawaii, USA
A high resolution imaging grating spectrometer has been designed to continuously investigate the solar corona using a small satellite on a sun synchronous orbit. To discriminate against the diffracted and scattered light from the solar disk a coronagraph set-up with 2 rectangular slits placed in sequence, using linear Lyot-type occulter and apertures, is positioned in front of the spectrometer using an off-axis parabolic and a spherical mirror. The second rectangular aperture acts also as the entrance slit for the spectrometer. The spectrometer uses echelle gratings operating in 40th to 50th order. The sensitivity and the resolution of the instrument makes it possible to measure velocities in the range of 20km/s to 2000km/s through Doppler spectroscopy. Using coatings with particularly low reflection coefficients a reduction of the solar stray light of 8 orders of magnitude is possible. Possible geometries and instrument parameters of the satellite's load will be discussed and compared with earlier results from previous solar eclipses.