The Libera Photon is a photon beam position processor, compatible with various detectors (e.g. diamond detectors, blade XBPMs and ionization chambers). It supports external BIAS source which is then applied to each of the 4 input channels. Position data is available at multiple configurable data rates and bandwidths. A dedicated RJ-45 interface can be used for real-time streaming data. With optional hardware upgrade, the analog and digital outputs enable the user to perform local feedback in the beamline.
- Best price/performance ratio
- Compact and robust design
- Power over Ethernet
- Source code available
- No maintenance required
- Variety of interfaces (e.g. EPICS, TANGO, HTTP, MATLAB, etc.)
At the input, there are four current-to-voltage converters with six ranges allowing measurements of currents from several pA to 2 mA. A/D conversion is done with 2.5 MHz 18-bit ADCs. The digital signal processing consists of signal conditioning and position calculation. Signal conditioning includes channel scaling and offset (dark current) removal and averaging over user-configurable window. Position calculation equation is user-configurable and can use various combinations of the input channels. The advantage of the Libera Photon is user-configurable IIR filtering and decimation for the fast and slow data streams. Two IIR filter blocks provide the user the freedom to develop the filter (e.g. in Matlab) and upload the coefficients to Libera Photon directly. The processed data are delivered to the user via four data paths.
The reference input (revolution clock) can be used to synchronize the data with the accelerator’s timing system.
- Additional RJ-45 interface for fast data streaming.
- Memory card slot.
- Serial console (Micro-B USB).
- RJ-45 for 1000Base-T Cu GbE connection and Power-over-Ethernet.
- USB slot.
- Connector for external BIAS voltage source
- TRIAX connectors for connections to the current detectors or sources.
- LEMO coaxial, used for various trigger signals (e.g. revolution clock, injection trigger).
The instrument can be used for both, fast changing and slow changing signals. The analog bandwidth varies over measurement ranges from 10 kHz (nA currents) up to 90 kHz (uA-mA currents).
RMS uncertainty on position data is evaluated on the fast data streams and on the low data streams (see table below). A typical temperature drift is measured approximately 10 nm/°C.
Libera Photon Performance
|Temperature drift, typical||0.01 μm/°C|
|8-hour stability (23°C, 200 μA)||0.02 μm|
|RMS uncertainty @ 180 μA (10 kHz data rate)||<0.02 μm|
|RMS uncertainty @ 180 μA (10 Hz data rate)||<0.01 μm|
The instrument runs on a Libera BASE software infrastructure. The infrastructure supports various plugins (interface servers) that are compatible with most common control system interfaces on users’ side:
- EPICS: libera-ioc
- TANGO: libera-ds
- MATLAB/LabVIEW: libera-telnet-server
- HTTP/WEB: libera-http-plugin
- C++ : libera-mci
- PYTHON: libera-pymci
Graphical user interface for TANGO users is built by the AtkPanel tool automatically. EPICS users have various options: from EDM, caQtDM to CSS.
As an example, the gallery below shows the GUI panels built on the caQtDM technology.
Photon Beam Position Measurements by Libera Photon Using Copper Blade Sensors at SOLEIL Synchrotron…BIW10, US
Kees ScheidtDiagnostics Head (ESRF, Grenoble)
On our Booster beam, we collected much data and features, that we could not measure or even detect before.
Engineering ExecutiveNDA locked
The prototyping and development Instrumentation Technologies has provided for our team has been exceptional.
Libera Photon is used at the following labs:
- Canadian Light Source – CLS (Canada)
- CORNELL UNIVERSITY – CHESS (United States)
- Argonne National Laboratory – APS (United States)
- KIT – Karlsruhe Institute of Technology – Forschungszentrum Karlsruhe– ANKA (Germany)
- Paul Scherrer Institute – SLS (Switzerland)
- National Synchrotron Radiation Laboratory – HLS/HLS II (China)
- High Energy Accelerator Research Organization (KEK) – PF (Japan)
- National Synchrotron Radiation Research Center – TLS, TPS (Taiwan)
- DIAMOND Light Source (United Kingdom)
- Societe civile – SOLEIL Synchrotron (France)
- Shanghai Synchrotron Radiation Facility (SINAP) – SSRF (China)
- The European Synchrotron Radiation Facility (ESRF) – ESRF, beamline (France)
- Hiroshima Synchrotron Radiation Center – HiSOR (Japan)
- Consortium for the Exploitation of the Synchrotron Light Laboratory (CELLS) – ALBA (Spain)
- Pohang Accelerator Laboratory (PAL) – PLS II (South Korea)
- Brookhaven National Laboratory (BNL) – NSLS II (United States)
- Institute of High Energy Physics (IHEP) – BEPC II (China)
- Max Planck Institute for Chemical Physics of Solids – MPG (Germany)
- Jagiellonian University – SOLARIS (Poland)
- Northwestern University (United States)