LUX-ZEPLIN

Abstract:

High resolution X-ray spectroscopy provides a powerful tool for the diagnosis of plasmas and extra terrestrial X-ray sources. We are developing detectors based on superconducting tunnel junctions which will provide position sensitive detectors with much better energy resolution than current state of the art CCD cameras. The amount of energy required to create a charge carrier in a superconductor is about three orders of magnitude smaller than in standard semiconductor detectors. Consequently, the energy resolution, especially in the energy range below a few keV, is significantly enhanced. The drawback of the necessarily small size of superconducting tunnel junctions has been compensated by a separation of X-ray absorber and detecting tunnel junction ('quasiparticle trapping'). We report on results with our detector which can resolve the 5.89 keV manganese line with an energy resolution of better than 60 eV. In addition position resolution better than 1 μm has been demonstrated with an absorber 470 μm long. To match the detector to the spot size of the X-ray optics in use, a multi element detector is under development.