Our spectrometers consist of multiple components with majority of them being designed by our team. In this part of webside we present information and specification about individual components that can be found inside or coupled with our spectrometers OLTWINS.
For better orientation, the content is divided into 5 sections:
- Control unit (electronics)
- Transducers
- Detectors
- Software
- Additional equipment
If you are unable to find relevant information about the components you seek, do not hesitatte to contact us. See the Contacts page on how to reach us!
Control Unit
Transducer/velocity modulation is based on the self-tuning MPC (model predictive control) procedure, thus no PID regulation is nedeed. Control unit is capable to drive two transducers independently. Concurrently control unit carries out signal shape discrimination on two independent signals from detectors. Signal lines from detectors are terminated by 50 Ω. PMT high voltage is controlled digitally from control unit and can be set independently on both PMTs. Control unit acquires two Mössbauer spectra each recorded in max. 2048 channels.
| Velocity modulation working frequency | 3–80 Hz |
| Excitation current waveform resolution | 12 bit |
| Pick up coil voltage measurement resolution | 12 bit |
| Max excitation current | from ±13 mA up to ±910 mA (keeping 12 bit resolution) |
| Pick up coil voltage limit | from −5 V to +5 V |
| Adjustable pick up coil voltage gain | 11 levels (from 0.125 to 128 by power of two) independently on each channel |
| Max. output voltage for external transducer current driver | ±2.5 V |
| Signal max. input voltage limit | from −0.5 V to +5 V |
| Signal max. voltage for MCA | from 0 V up to +2.5 V |
| MCA levels resolution | 12 bit |
| PMT high voltage settings | from 0 to +1250 V with 12 bit resolution |
Amplifier
Our amplifier consist of two stages: transimpedance amplifier (I to V converter) and noninverting amplifier. Output voltage is series terminated by 50 Ω. Signal is shaped by adjustable RC integrator.
| Transimpedance gain | 3.3 kΩ |
| Noninverting amplifier gain | 3 – 47 (manualy adjustable) |
| Shaping integration constant | from 10 ns to 1010 ns (manualy adjustable) |
Transducers
Tranducers/velocity drives are devices that are used to modulate the energy of the radioactive photons via Doppler´s effect. OLTWINS spectrometers can be operated with several different types of transducers, depending on the application.
Oltwins PIGLET
Mössbauer "PIGLET" transducer is sufficiently large to be capable of moving the both detector with a sample or a radioactive source.
Specifications
| Dimensions | 450/200/200 mm |
| Weight | 25 kg |
Oltwins HAMSTER
In contrast to "PIGLET", the "HAMSTER" is unique in its small dimensions. However, on contrary to its size it still retains the excelent properties of much larger transducers. The tranducer is meant to be mounted with radioactive source.
Specifications
| Dimensions | 70/25/25 mm |
| Weight | 110 g |
"PIGLET" and "HAMSTER" comparison
Detector
Scintilation detectors
The scintillation detectors complemented with HAMAMATSU photomultipliers with integrated HV source are used for radiation detection. The YAP:Ce crystals from CRYTUR company are utilized as scintillation material.
Typical multichannel analysis of the signnal from our detector:
Toroidal gas detector “DONUT” for back scattering arrangement
Another option is the use of proportional detectors developed at our department, for example, specially designed toroidal proportional detector.
Software
The spectrometer is operated by an original software with a graphical user interface (GUI, based on Qt5) with simultaneous displaying of the measured spectra. The software can be run under Linux (OpenSuse) or Windows operating system. There is also possibility of simple scripting, which allows easy incorporation into larger experimental setups.
Example of running software under Linux
