Entwicklung und Charakterisierung von Instrumenten zur hochauflösenden Spektropolarimetrie [article]

Matthias Johannes Schubert, University, My, University, My
2019
Context Our Sun is an unique high-energy plasma physics laboratory, which can be studied with exceptional spatial and temporal resolution. Using dedicated telescopes, it is possible to verify and enhance our knowledge about aspects of modern physics unaccessible to any experiments on earth. State of the art magneto-hydrodynamic simulations of the solar photosphere have a spatial resolution of 6km at a wavelength of 500nm and model the dynamics of solar pores, sunspots and coronal mass
more » ... onal mass ejections. The theoretical models have to be evaluated in different atmospheric heights with highly resolving spectro- olarimetric observations. Therefore, the international solar community started to build a 4m-class telescope. Furthermore an imaging spectro-polarimeter for visible light is developed. This is an unique tool to access highly dynamical, small scale processes on the solar photosphere and chromosphere for ground breaking scientific research. Objectives Development of a simulation algorithm to describe the influence of instrumental imperfections on two dimensional spectro- polarimetric observations. The aim is to study the consequences for physical measurement accuracy. The filter instrument consists of two or three Fabry-Pérot-Interferometers in telecentric mounting, a pre-filter and a polarisation modulator. Since induced errors are relevant for scientific research it was also necessary to develop and study a dedicated new calibration algorithms. The simulated measurement errors in combination with the newly developed calibration method enables us to define limits for the manufacturing process of the filter instrument to achieve the demanded accuracy. Methods Since a similar, yet smaller instrument is operated at the Vacuum-Tower- Telescope on the Canarian Island Tenerife, it was used as a test bed to characterize realistic instrumental induced errors. This defined the relevant parameters of the filter instrument for scientific research which were modelled: the etalons surface micro roughness, a varying reflectivity, [...]
doi:10.34657/1513 fatcat:k4zywuq3wvarhi6pppwa45fgy4