The European X-ray Free-Electron Laser (XFEL) at Deutsches Elektronen-Synchrotron (DESY), Hamburg, Germany is a user facility providing ultra-short hard and soft X-ray flashes with a high brilliance. All low level radio frequency (LLRF) stations of the injector, covering the normal conducting RF gun, A1 (8 1.3 GHz superconducting cavities (SCCs)) and AH1 (8 3.9 GHz SCCs), were successfully commissioned by the end of 2015. The commissioning of LLRF stations A2 to A23 (32 1.3 GHz SCCs each) in the XFEL accelerator tunnel (XTL) was concluded in June 2017. Self-amplified spontaneous emission (SASE) light was produced in undulator section SA1 and delivered to the first users in September 2017, marking the beginning of regular user operation. The current state of the LLRF systems, the experience gained during operation and the performance achieved in terms of stability and energy reach are presented.

The superconducting linear accelerator ELBE at Helmholtz-Zentrum Dresden-Rossendorf is operated in continuous wave (CW) operation [1]. The analogue LLRF (low level radio frequency) system, used since 2001, is going to be replaced by a digital solution based on MicroTCA.4. The new system enables a higher flexibility, better performance and more advanced diagnostics. The contribution shows the performance of the system at ELBE, the hardware and the software structure. Further it will summarize the last steps to bring it into full user operation and give an outlook to the envisioned beam-based feedback system that will take advantage of the capabilities of the digital LLRF system.

Ensuring software quality is important, especially for control system applications. Writing tests for such applications requires replacing the real hardware with a virtual implementation in software. Also the rest of the control system which interacts with the application must be replaced with a mock. In addition, time must be controlled precisely. We present the VirtualLab framework as part of the Chimera Tool Kit (formerly named MTCA4U). It has been designed to help implementing such tests by introducing the concept of virtual time, and combining it with an implementation basis for virtual devices and plant models. The virtual devices are transparently plugged into the application in place of real devices. Also tools are provided to simplify the simu-lated interaction with other parts of the control system. The framework is designed modularly so that virtual devices and model components can be reused to test different parts of the control system software. It interacts seamlessly with the other libraries of the Chimera Tool Kit such as DeviceAccess and the control system adapter.

We present a study of showers initiated by electrons, pions, kaons, and protons with momenta from 15 GeV to 150 GeV in the highly granular CALICE scintillator-tungsten analogue hadronic calorimeter. The data were recorded at the CERN Super Proton Synchrotron in 2011. The analysis includes measurements of the calorimeter response to each particle type as well as measurements of the energy resolution and studies of the longitudinal and radial shower development for selected particles. The results are compared to Geant4 simulations (version 9.6.p02). In the study of the energy resolution we include previously published data with beam momenta from 1 GeV to 10 GeV recorded at the CERN Proton Synchrotron in 2010.

Lepton colliders are considered as options to complement and to extend the physics programme at the Large Hadron Collider. The Compact Linear Collider (CLIC) is an e(+)e(-) collider under development aiming at centre-of-mass energies of up to 3 TeV. For experiments at CLIC, a hadron sampling calorimeter with tungsten absorber is proposed. Such a calorimeter provides sufficient depth to contain high-energy showers, while allowing a compact size for the surrounding solenoid.A fine-grained calorimeter prototype with tungsten absorber plates and scintillator tiles read out by silicon photomultipliers was built and exposed to particle beams at CERN. Results obtained with electrons, pions and protons of momenta up to 10 GeV are presented in terms of energy resolution and shower shape studies. The results are compared with several GEANT4 simulation models in order to assess the reliability of the Monte Carlo predictions relevant for a future experiment at CLIC.

The intrinsic time structure of hadronic showers influences the timing capability and the required integration time of hadronic calorimeters in particle physics experiments, and depends on the active medium and on the absorber of the calorimeter. With the CALICE T3B experiment, a setup of 15 small plastic scintillator tiles read out with Silicon Photomultipliers, the time structure of showers is measured on a statistical basis with high spatial and temporal resolution in sampling calorimeters with tungsten and steel absorbers. The results are compared to GEANT4 (version 9.4 patch 03) simulations with different hadronic physics models. These comparisons demonstrate the importance of using high precision treatment of low-energy neutrons for tungsten absorbers, while an overall good agreement between data and simulations for all considered models is observed for steel.

The MicroTCA.4 crate standard provides a powerful electronic platform for digital and analogue signal processing. Besides excellent hardware modularity, it is the software reliability and flexibility as well as the easy integration into existing software infrastructures that will drive the widespread adoption of the new standard. The DESY MicroTCA.4 User Tool Kit (MTCA4U) comprises three main components: A Linux device driver, a C++ API for accessing the MicroTCA.4 devices and a control system interface layer. The main focus of the tool kit is flexibility to enable fast development. The universal, expandable PCI Express driver and a register mapping library allow out of the box operation of all MicroTCA.4 devices which are running firmware developed with the DESY board support package. The tool kit has recently been extended with features like command line tools and language bindings to Python and Matlab.

The CLIC Detector and Physics Study H. Abramowicz1, A. Abusleme2, K. Afanaciev3, G. Alexander1, N. Alipour Tehrani4, O. Alonso5,6, K.K. Andersen7, S. Arfaoui4, C. Balazs8,9, T. Barklow10, M. Battaglia11, M. Benoit4, B. Bilki12, J.-J. Blaising13, M. Boland8,14, M. Boronat5,15, I. Božović Jelisavčić16, P. Burrows17, M. Chefdeville13, R. Contino18, D. Dannheim4, M. Demarteau12, M.A. Diaz Gutierrez2, A. Diéguez5,6, J. Duarte Campderros5,19, G. Eigen20, K. Elsener4, D. Feldman21, U. Felzmann8,14, M. Firlej22, E. Firu23,

A prototype Time Projection Chamber with 26 cm drift length was operated with a short-spaced triple GEM stack in a setup triggering on cosmic muon tracks. A small part of the anode plane is read-out with a CMOS pixel-ASIC, the Timepix chip providing ultimate readout granularity. Clusters of charge depositions corresponding to single primary electrons are observed and analyzed to reconstruct charged particle tracks. A data set of several weeks of cosmic ray data is analyzed. The number of clusters per track length is well described by simulation. The obtained single point resolution approaches 50 μm at short drift distances and is well reproduced by a simple model of single electron diffusion.

The EUDET-project was launched to create an infrastructure for developing and testing new and advanced detector technologies to be used at a future linear collider. The aim was to make possible experimentation and analysis of data for institutes, which otherwise could not be realized due to lack of resources. The infrastructure comprised an analysis and software network, and instrumentation infrastructures for tracking detectors as well as for calorimetry.

Gas Electron Multipliers (GEMs) and Micromegas have demonstrated a very good performance in many applications. In particular, the spatial resolution has improved significantly compared to wire-based gaseous detectors. Because of the small pitch between the sensitive areas of gas amplification the limiting factor is usually given by the readout structure. To fully exploit the benefits of MPGDs we used a Timepix chip, a CMOS pixel chip with a pixel pitch of 55 μm, in combination with a GEM stack or a Micromegas realized as an InGrid structure. Both combinations have been tested in a time projection chamber (TPC) with a maximum drift distance of 26 cm. Additionally, various pad sizes have been studied with the GEM setup to investigate their influence on several key parameters. Also, first measurements of an InGrid based X-ray detector are described. In particular, measurements of background events were performed to evaluate a possible application of the detector in low rate dark matter searches.

This contribution reports on measurements with a GEM based TPC using the TimePix CMOS ASIC as a charge collecting readout anode. Tests on a small prototype with a 6 mm drift space were performed in a 5 GeV electron beam at DESY. The point resolution for short drift distances is better than 20 μm. A time resolution as good as 8 ns at 100 MHz clock frequency is achieved. Furthermore, experimental studies with an enlarged pixel size are addressed. Currently an UV/laser test bench is under development. The UV-laser will release single or a few photo electrons from the drift cathode, which are correlated in space and time. This correlation allows detailed studies of detection efficiencies and gas amplification processes in Micro-Pattern-Gas-Detectors. For the EUDET test beam at DESY a software is developed to integrate the pixel-readout based data acquisition there. ∗University of Freiburg, Freiburg, Germany †University of Bonn, Bonn, Germany

This memo reports on the progress of the development of a highly pixelated and integrated readout system for a TPC. A triple GEM stack is used for gas amplification. The readout is performed using the TimePix CMOS ASIC developed within the EUDET/SiTPC collaboration. The spatial as well as the time resolution of the GEM-TimePix system are probed in a 5GeV electron test beam at DESY. Furthermore advances in hardware development, achieved in collaboration with CERN and the FMF in Freiburg, are presented. 1 Albert-Ludwigs University, Freiburg, Germany 2 Rheinische Friedrichs-Wilhelms-University, Bonn, Germany 3 Freiburger Material Forschungszentrum, Freiburg, Germany 4 CERN, Geneva, Switzerland 5 CEA Saclay, DAPNIA/SPP, Gif sur Yvette, France

A large Time Projection Chamber (TPC) is proposed as part of the tracking system for a detector at the future electron positron linear collider. The Linear Collider TPC (LCTPC) Collaboration is currently building a large TPC prototype (60 cm long, with an outer radius of 77 cm), offering some modularity to investigate various gas amplification systems (GEM or Micromegas), pad sizes and geometries as well as different read-out systems. Detector technologies based on silicium will also be investigated. In this memo, we present the read-out systems that will be used with gas detectors for this large prototype, the connection to the EUDET central data acquisition system as well as the slowcontrol.

In this report the current status of the EUDET computing cluster at the university of Bonn is outlined. The cluster has one Computing Element, one batch head– node and 8 Worker Nodes. In addition there is a Storage Element managed by dCache. There is also a grid User Interface and a machine on which site monitoring services run. The cluster has been set up in the physics institute’s main computing room where it’s mounted in one of the racks. An appropriate redundant cooling plant has been built maintaining the room at constant working temperature. The cluster is grid enabled and utilizes WLCG grid middleware. ∗University of Bonn, Bonn, Germany

A large Time Projection Chamber (TPC) is proposed as part of the tracking system for a detector at the future electron positron linear collider. The Linear Collider TPC (LCTPC) Collaboration is currently building a large TPC prototype (60 cm long, with an outer radius of 77 cm), offering some modularity to investigate various gas amplification systems (GEM or Micromegas), pad sizes and geometries as well as different read-out systems. Detector technologies based on silicium will also be investigated. In this memo, we present the read-out systems that will be used with gas detectors for this large prototype, the connection to the EUDET central data acquisition system as well as the slowcontrol.

We report on measurements of charge transfer in GEM structures in high magnetic fields. These were performed in the framework of the R&D work for a Time Projection Chamber at a future Linear Collider. A small test chamber has been installed into the aperture of a superconducting magnet with the GEM structures mounted perpendicular to the B field direction. The charge transfer is derived from the electrical currents monitored during irradiation with an Fe source. No severe loss of primary ionisation charge is observed, but an improved ion feedback suppression is achieved for high magnetic fields. Additionally, the width of the charge cloud released by individual Fe photons is measured using a finely segmented strip readout after the triple GEM structure. Charge widths between 0.3 and 0.5 mm RMS are observed, which originate from the charge broadening inside the GEM readout. This charge broadening is only partly suppressed at high magnetic fields.

The physics goals and the expected environment at the ILC requires the development of a detector with unprecedented tracking capabilities. A high-resolution TPC with gas amplification based on micro-pattern gas detectors is a promising candidate for the main tracker at the ILC detector. Significant progress has been achieved in the development of a TPC concept with Gas Electron Multipliers (GEM [F. Sauli, Nucl. Instr. and Meth. A 386 (1997) 531]) used for gas amplification.Significant ion backdrift reduction was obtained using special settings of the GEM structures. To further study the spatial resolution of a GEM-based TPC, a prototype with low-mass fieldcages was constructed. It was operated within a high-resolution silicon hodoscope. Additionally, extensive effort is spent on the development of an accurate numerical simulation of the TPC properties, such as drift, diffusion and gas amplification. (c) 2006 Elsevier B.V. All rights reserved.

A shelf comprising a base part (2) and at least one side (3) rigid with said base part, in which to enable the side (3) to be varied in position relative to the base part (2) and to maintain the position assumed, the side (3) and base part (2) are joined together by at least two deformable elements.