학술논문

Multi-Processor Based Fast Data Acquisition for a Free Electron Laser and Experiments
Document Type
Periodical
Source
IEEE Transactions on Nuclear Science IEEE Trans. Nucl. Sci. Nuclear Science, IEEE Transactions on. 55(1):256-260 Feb, 2008
Subject
Nuclear Engineering
Bioengineering
Data acquisition
Free electron lasers
X-ray lasers
Control systems
Video sharing
Digital cameras
Orbital calculations
Feedback loop
Stability
Linear particle accelerator
Accelerator control systems
data acquisition
free electron laser
software
Language
ISSN
0018-9499
1558-1578
Abstract
Free electron LASer in Hamburg (FLASH) at DESY is a user facility with laser-like radiation source in the VUV and soft X-ray range. It is also a pilot facility for the future XFEL. A fast data acquisition system (DAQ) to support the accelerator operation and the user experiments was developed. The system collects data from hundreds of ADC channels in the range of 1M up to 2G samples per second. In addition it allows collecting images from digital video cameras. All the data is collected in a shared memory of a central multiprocessor computer. Several processes are used to calculate e.g., the orbit, energy or photon flux, or are used as feedback loops to improve the stability of the linac. A long time archiving of the collected data from the accelerator and from the FEL experiments on a 24 TB disk and finally on a tape is provided. The whole system is integrated in the DOOCS control system of FLASH. It is a novel approach to combine a fast DAQ system with a accelerator control system.