Hannover 2016 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
Q: Fachverband Quantenoptik und Photonik
Q 44: Precision spectroscopy of atoms and ions (with A)
Q 44.24: Poster
Wednesday, March 2, 2016, 16:30–19:00, Empore Lichthof
Polar-maXs: Micro-calorimeter based X-ray polarimeters — •Christian Schötz1, Daniel Hengstler1, Loredana Gastaldo1, Sebastian Kempf1, Andreas Fleischmann1, Christian Enss1, Günter Weber2,3, and Thomas Stöhlker2,3,4 — 1Kirchhoff Institute for Physics, Heidelberg University — 2Helmholtz-Institute Jena — 3GSI Darmstadt — 4IOQ, Jena University
We are presently developing the x-ray detector system Polar-maXs, which will combine for the first time the high energy resolution, large dynamic range and excellent linearity of magnetic micro-calorimeters with the sensitivity to polarization caused by polarization-dependent Compton or Rayleigh scattering in an array of scatterers.
Polar-maXs consists of two layers. The first layer comprises a 4 x 4 array of x-ray scatterers behind a corresponding array of collimator holes. Depending on the energy range of interest and whether Compton or Rayleigh scattering is to be used, these scatterers are fabricated from low-Z or high-Z material. The scattered x-rays are detected by an array of 576 x-ray absorbers read-out by paramagnetic temperature sensors as metallic magnetic micro-calorimeters (MMC). Each absorber covers an area of 0.5mm x 0.5mm and is made of 15 micrometer thick gold, to guarantee high stopping power for x-ray with energies up to 20 keV and an energy resolution of better than 20eV (FWHM) in the complete energy range. We discuss general design considerations as well as the results of Monte-Carlo simulations for a variety of detector designs. We present micro-fabricated devices and discuss the results of first experimental tests.