Design of TDS-based Multi-screen Electron Beam Diagnostics for the European XFEL

Dedicated longitudinal electron beam diagnostics is essential for successful operation of modern free-electron lasers. Demand for diagnostic data includes the longitudinal bunch profile, bunch length and slice emittance of the electron bunches. Experimental setups based on transverse deflecting structures (TDS) are excellent candidates for this purpose. At the Free-Electron Laser in Hamburg (FLASH), such a longitudinal bunch profile monitor utilizing a TDS, a fast kicker magnet and an off-axis imaging screen, has been put into operation. It enables the measurement of a single bunch out of a bunch train without affecting the remaining bunches. At the European X-ray Free-Electron Laser (XFEL) multiscreen stations in combination with TDS are planned to be installed. In order to allow for flexible measurements of longitudinal bunch profile and slice emittance, a configurable timing and trigger distribution to the fast kicker magnets and screen stations is required. In this paper, we discuss various operation patterns and the corresponding realization based on MTCA.4 technology

GUI Application for ATCA-based LLRF Carrier Board Management

The Advanced Telecommunications Computing Architecture (ATCA) standard describes an efficient and powerful platform, implementation of which was adopted to be used as a base for control systems in high energy physics. The ATCA platform is considered to be applied for the X-ray Free Electron Laser (X-FEL), being built at Deutsches Electronen- Synchrotron (DESY) in Hamburg, Germany. The Low Level Radio Frequency (LLRF) control system is composed of a few ATCA Carrier Boards. Carrier Board hosts Intelligent Platform Management Controller (IPMC), which is developed in compliance with the PICMG specifications. IPMC is responsible for management and monitoring of sub-modules installed on Carrier Boards and pluggable Advanced Mezzanine Card (AMC) modules. The ATCA Shelf Manager is the main control unit of a single ATCA crate, responsible for all power and fan modules and Carrier Boards installed in ATCA shelf. The device provides a system administrator with a set of control and diagnostic capabilities regarding the crate and its sub-modules. These capabilities offered by Shelf Management are available for operators and can be further processed by higher layer applications. This paper presents a software component, the purpose of which is to support the management and supervision processes of the ATCA crate and its sub-modules, including ATCA Carrier Board devices with AMC modules. The application allows to acquire detailed information regarding status and parameters of crucial devices (e.g. power supply voltages, temperatures, presence of reference clocks). The combination of information supplied from Shelf Manager with graphical environment and user interface of the application provides visual representation of selected system components and contributes towards efficient control and supervision activities over Carrier Board and entire ATCA-based platform

Integrating Control Applications into Different Control Systems

Porting complex device servers from one control system to another is often a major effort due to the strong code coupling of the business logic to control system data structures. Together with its partners from the Helmholtz Association and from industry, DESY is developing a control system adapter. It allows to write applications in a control system independent way, while still being able to update the process variables and react on control system triggers. We report on the status of the project and the experience we gained trying to write portable device servers

Image Visualisation and Processing in DOOCS and EPICS

Abstract—The High Energy Physics (HEP) experiments, due to their large scale, required performance and precision, have to be controlled by complex, distributed control systems. The systems are responsible for processing thousands of signals from various sensors of different types. Very often, one of the data sources applied in such systems are visible light/infrared cameras or other imaging sensors. They can provide additional information about studied phenomena, which is not available on the basis of analysis data from other sensors. However, they require dedicated mechanisms for data collecting and processing. Moreover, often the images from cameras should be available to system operator. It needs the support from both operator panels interface and control application which should provide data in the dedicated format. The paper presents two different approaches to image distribution, processing and visualisation applied in distributed control systems. Discussed is the issue of support for cameras and image data implemented in the Distributed Object Oriented Control System (DOOCS) and an example control system designed to the needs of image acquisition system on the base o

First Realization and Performance Study of a Single-Shot Longitudinal Bunch Profile Monitor Utilizing a Transverse Deflecting Structure

For the control and optimization of electron beam parameters at modern free-electron lasers (FEL), transverse deflecting structures (TDS) in combination with imaging screens have been widely used as robust longitudinal diagnostics with single-shot capability, high resolution and large dynamic range. At the free-electron laser in Hamburg (FLASH), a longitudinal bunch profile monitor utilizing a TDS has been realized. In combined use with a fast kicker magnet and an off-axis imaging screen, selection and measurement of a single bunch out of the bunch train with bunch spacing down to 1us can be achieved without affecting the remaining bunches which continue to generate FEL radiation during user operation. Technical obstacles have been overcome such as suppression of coherent transition radiation from the imaging screen, the continuous image acquisition and processing with the bunch train repetition rate of 10Hz. The monitor, which provides the longitudinal bunch profile and length, has been used routinely at FLASH. In this paper, we present the setup and operation of the longitudinal bunch profile monitor as well as the performance during user operation

Integrating Real-Time Control Applications into Different Control Systems

Porting complex device servers from one control system to another is often amajor effort due to the strong code coupling of the business logic to control system data structures.Together with its partners from the Helmholtz Association and from industry,DESY is developing a control system adapter as part of the MTCA4U tool kit.It allows to writeapplications in a control system independent way, while still being able toupdate the process variables and react on control system triggers.Special attention has been paid to make the implementation thread safe andreal time capable, while still providing the required abstraction and avoidingperformance losses.We report on the status of the project and the plans to implement new features

Drivers and Software for MicroTCA.4

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. Themain focus of the tool kit is flexibility to enable fast development. The universal, expandable PCIexpress driver and a register mapping library allow out of the box Operation of all MicroTCA.4 devices which carry firmware developed with the DESY FPGA board support package. The controlsystem adapter provides callback functions to decouple the application code from the middleware layer. Like this the same business logic can be used at different facilities without further modification

ChimeraTK - A Software Tool Kit for Control Applications

The presentation provides an overview of the ChimeraTK framework. The project started from a demand for software libraries that provide convenient access to PCIE bus based cards on the MicroTCA.4 platform. Previously called MTCA4U, ChimeraTK is evolving towards a set of frameworks and tools that enable users to build up control applications, while abstracting away specifics of the underlying system. Initially, the focus of the project was the DeviceAccess C++ library and its bindings for Matlab and Python, along with a Qt based client that used DeviceAccess under the hood. However, ChimeraTK has expanded to include more tools like the ControlSystemAdapter, VirtualLab and ApplicationCore. The ControlSystemAdapter framework focuses on tools that enable application code to be written in a middle ware agnostic manner. VirtualLab focuses on facilitating testing of application code and providing functional mocks. The ApplicationCore library aims at unifying application interfaces to other tools in the toolkit and improving abstraction. We present an update on improvements to the project and discuss motivations and applications for these new set of tools introduced into the toolkit