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International audience; Time-resolved pump-probe experiments at SOLEIL Synchrotron (France) have motivated the development of a new and fast photon counting camera prototype. The core of the camera is a hybrid pixel detector, based on the UFXC32k readout chips bump-bonded to a silicon sensor. This detector exhibits promising performances with very fast readout time, high dynamic range, extended count rate linearity and optimized X-ray detection in the energy range 5-15 keV. In close collaboration with CRISTAL beamline, SOLEIL’s Detector, Electronics and Software Groups carried out a common R&D project to design and realize a 2-chips camera prototype with a high-speed data acquisition system. The system has been fully integrated into Tango and Lima data acquisition framework used at SOLEIL. The development and first experimental results will be presented in this paper.

This paper gives an overview of some feedback & control systems in Synchrotron SOLEIL that are in use or in development today. Electron Beam stability is something that is being addressed in several SOLEIL applications; Fast Orbit Feedback is a multi-input multi-output control system made to stabilize beam position perturbations with slow and fast corrections. In addition, active RF cavities are used to maintain stable beam energy & spread as well as keeping electron density even throughout the storage ring. Beam stability also comes from feedforward non-linear control in particle trajectory compensation on both sides of electromagnetic undulators. On beamlines, multi-actuator piezos or pneumatics are used to regulate photon flux to keep within detector operating range; a method to maximize the photon flux while keeping detector below damage thresholds. Currently in development at the sample stage level, the Nanoprobe Project (collaboration MAXIV & Soleil) focuses on sample stabilization during step- & fly- scans which is realized through multi-axis nano-positioning with high- & low- frequency closed-loop control implementing interferometer feedback &/or compensation tables., Proceedings of the 11st Int. Workshop on Personal Computers and Particle Accelerator Controls, PCaPAC2016, Campinas, Brazil

The aim of the project, of which the work described in this thesis is part, was to design a high-speed X-ray camera using hybrid pixels applied to biomedical imaging and for material science. As a matter of fact the hybrid pixel technology meets the requirements of these two research fields, particularly by providing energy selection and low dose imaging capabilities. In this thesis, high frame rate X-ray imaging based on the XPAD3-S photons counting chip is presented. Within a collaboration between CPPM, ESRF and SOLEIL, three XPAD3 cameras were built. Two of them are being operated at the beamline of the ESRF and SOLEIL synchrotron facilities and the third one is embedded in the PIXSCAN II irradiation setup of CPPM. The XPAD3 camera is a large surface X-ray detector composed of eight detection modules of seven XPAD3-S chips each with a high-speed data acquisition system. The readout architecture of the camera is based on the PCI Express interface and on programmable FPGA chips. The camera achieves a readout speed of 240 images/s, with maximum number of images limited by the RAM memory of the acquisition PC. The performance of the device was characterize by carrying out several high speed imaging experiments using the PIXSCAN II irradiation setup described in the last chapter of this thesis., L'objectif du projet, dont le travail présenté dans cette thèse est une partie, était de développer une caméra à rayons X ultra-rapide utilisant des pixels hybrides pour l'imagerie biomédicale et la science des matériaux. La technologie à pixels hybrides permet de répondre aux besoins des ces deux champs de recherche, en particulier en apportant la possibilité de sélectionner l'énergie des rayons X détectés et de les imager à faible dose. Dans cette thèse, nous présentons une caméra ultra-rapide basée sur l'utilisation de circuits intégrés XPAD3-S développés pour le comptage de rayons X. En collaboration avec l'ESRF et SOLEIL, le CPPM a construit trois caméras XPAD3. Deux d'entre elles sont utilisée sur les lignes de faisceau des synchrotrons SOLEIL et ESRF, et le troisième est installé dans le dispositif d'irradiation PIXSCAN II du CPPM. La caméra XPAD3 est un détecteur de rayons X de grande surface composé de huit modules de détection comprenant chacun sept circuits XPAD3-S équipés d'un système d'acquisition de données ultrarapide. Le système de lecture de la caméra est basé sur l'interface PCI Express et sur l'utilisation de circuits programmables FPGA. La caméra permet d'obtenir jusqu'à 240 images/s, le nombre maximum d'images étant limité par la taille de la mémoire RAM du PC d'acquisition. Les performances de ce dispositif ont été caractérisées grâce à plusieurs expériences à haut d'ebit de lecture réalisées dans le système d'irradiation PIXSCAN II. Celles-ci sont décrites dans le dernier chapitre de cette thèse.

Time-resolved pump-probe experiments at SOLEIL Synchrotron (France) have motivated the development of a new and fast photon counting camera prototype. The core of the camera is a hybrid pixel detector, based on the UFXC32k readout chips bump-bonded to a silicon sensor. This detector exhibits promising performances with very fast readout time, high dynamic range, extended count rate linearity and optimized X-ray detection in the energy range 5-15 keV. In close collaboration with CRISTAL beamline, SOLEIL’s Detector, Electronics and Software Groups carried out a common R project to design and realize a 2-chips camera prototype with a high-speed data acquisition system. The system has been fully integrated into Tango and Lima data acquisition framework used at SOLEIL. The development and first experimental results will be presented in this paper., Proceedings of the 17th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2019, New York, NY, USA