The first DEPFET module (128 x 512 pixels) of the DSSC pixel detector, designed for user experiments at the European XFEL, has been fully instrumented and an experimental campaign has been carried ...out with X-ray lines to qualify the main performance figures and to collect calibration data. X-ray spectra fitting has been optimized with consideration to the main sources of systematic errors to achieve gain calibration within 1% accuracy, which is a key issue for its successful operation at the European XFEL. The most important result is the equivalent noise charge of 16 el rms on average. This shows the potential of the DEPFET-based pixel to reach single-photon imaging down to the lowest photon energy (0.25 keV) at 4.5 MHz frame frequency that can be extrapolated at camera level with high confidence.
Performances of the Gas Gain Monitoring system of the CMS RPC muon detectors after one year of operation at the scaled down closed loop recirculation gas system are presented. The GGM is made of 12 ...single-gap RPC's arranged in a cosmic ray telescope, with charge readout for online monitoring of working point. Preliminary results on sensitivity to gas changes and to environmental variables will be reported on.
The first DSSC 1-Mpixel camera became available at the European XFEL (EuXFEL) in the Hamburg area in February 2019. It was successfully tested, installed, and commissioned at the Spectroscopy and ...Coherent Scattering Instrument. DSSC is a high-speed, large-area, 2-D imaging detector system optimized for photon science applications in the energy range between 0.25 and 6 keV. The camera is based on direct conversion Si sensors and is composed of <inline-formula> <tex-math notation="LaTeX">1024 \times 1024 </tex-math></inline-formula> pixels of hexagonal shape with a side length of <inline-formula> <tex-math notation="LaTeX">136~\mu \text{m} </tex-math></inline-formula>. The 256 application-specific integrated circuits (ASICs) provide full parallel readout, comprising analog filtering, digitization, and in-pixel data storage. In order to cope with the demanding X-ray pulse time structure of the EuXFEL, the DSSC provides a peak frame rate of 4.5 MHz. The first Mpixel camera is equipped with miniaturized silicon drift detector (MiniSDD) pixel arrays. The intrinsic response of the pixels and the linear readout limit the dynamic range but allow one to achieve noise values of about 60 electrons r.m.s. at the highest frame rate. The challenge of providing high-dynamic range (~10 4 photons/pixel/pulse) and single-photon detection simultaneously requires a nonlinear system front end, which will be obtained with the DEPFET active pixel technology foreseen for the advanced version of the camera. This technology will provide lower noise and a nonlinear response at the sensor level. This article describes the architecture of the whole detector system together with the main experimental results achieved up to now.
The CMS RPC gas gain monitoring system: An overview and preliminary results Benussi, L.; Bianco, S.; Colafranceschi, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2009, Letnik:
602, Številka:
3
Journal Article
Recenzirano
The status of the Compact Solenoid Spectrometer (CMS) Resistive Plate Counter (RPC) Gas Gain Monitoring (GGM) system developed at the Frascati Laboratory of INFN (Istituto Nazionale di Fisica ...Nucleare) is reported. The GGM system is a cosmic ray telescope based on small RPC detectors operated with the same gas mixture used by the CMS RPC system. The GGM gain and efficiency are continuously monitored on-line, thus providing a fast and accurate determination of any shift in working point conditions. The construction details and the first result of GGM commissioning are described.
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