Introduction - Trains and Pulses¶
This overview focuses on information that is needed to understand the structure of the data produced at European XFEL, and how to analyse it. For a more general overview see the 'Facility' page on the European XFEL website .
Trains and Pulses¶
European XFEL generates a pulse train of up to 2700 individual X-ray pulses, at a rate of 10 trains per second (10Hz). Within a train, pulses arrive with a maximum frequency of 4.5 MHz (220 ns between pulses).
Each train receives a unique integer macro number, the so-called trainId.
This trainId is utilized in the data files for indexing. Hence, the DAQ writes data per trainId to disk. If more data per train is required, it is related to the pulse numbers.
Information about the pulses generated in each SASE can be recorded with
a BUNCH_DECODER device. This is a subset of the raw ‘bunch pattern’ data
available through a TIMESERVER device.
Chapter Overview¶
The following sections describe in detail, the EuXFEL data acquistion system:
- DAQ Workflow - Complete DAQ configuration workflow to start a run
- DAQ Devices - This chapter provides information about all DAQ devices and their technical responsibility
- Data Source Group Deployment - configure a run configuration group
- Environment and Access - information about your user account and what access is available at different stages during your proposal
- Data Files - overview of the structure of proposal data folders, the data format, inspection of data files
- Trouble Shooting - specific examples of software and toolboxes for instruments
- Setup DAQ on local system - Documentation on setting up and running DAQ on a local linux based system