Seminars Archive

Fri 14 Jul, at 14:00 - Seminar Room T2

Applications of MÖNCH for soft X-rays (and more)

Marco Ramilli
Paul Scherrer Institut, Villigen PSI, Switzerland

MÖNCH is a hybrid silicon pixel detector based on charge integration and with analog readout, featuring a pixel size of 25x25 μm2. Several prototypes have been commissioned, aimed at experimenting different solutions to optimize the detector performances for high and low flux applications at synchrotrons and X-FELs. With a noise of the order of 35 electrons RMS, MÖNCH is competitive with monolithic detectors and with CCDs in the fields of high resolution imaging and soft X-ray detection below the keV level, and its kHz frame rate capability can substantially shorten the time needed for a single measurement. With these low noise levels, the detector has also the potential for good energy resolution capabilities. However, the small pixel pitch and the consequent high occurrence of charge sharing often make clustering necessary to correctly reconstruct the photon energy. In this case, the energy resolution varies between 130 eV and 400 eV RMS, depending on the dimension of the cluster. Due to its extremely small pixel pitch, MÖNCH intrinsically features an elevate position resolution which, in low flux condition, can even overcome the pixel size: charge sharing between neighboring pixel can be exploited in position interpolation algorithms which can achieve a sub-micron resolution. A position sensitive detector with spectroscopic capabilities like MÖNCH can bring significant improvement in the experimental conditions of many kinds of experiments, ranging from soft X-ray applications to energy dispersive measurements like Laue diffraction. Results of pilot experiments aiming to test the detector performances will be presented and discussed.

(Referer: R. Menk)
Last Updated on Tuesday, 24 April 2012 15:21