Specialized Digital Electronics

All "neutron in, gamma out" methods require very high throughput from data acquisition system (DAQ). Typical counting rate of an associated alpha-particle detector installed inside a neutron generator (APT/NNA) is about 10⁶ counts per second. Each of the detectors of secondary gamma-radiation counts about 10⁵ gamma-rays per second. For each gamma-ray its energy and time-of-flight relative to the associated alpha-particle must be determined. Traditional analogue electronics doesn't meet the abovementioned requirements.

APSTEC has developed data acquisition system for use in any "neutron in, gamma out" method, including APT/NNA, which is based on modern flash ADCs, programmable logic devices (PLD) and digital signal processors (DSP).

Alpha-detection module (1)

Gamma-detection module (2)

PC-controlled HV power supplies (3)

It includes the following components:
1. alpha-detection module, which can handle count rates up to 10⁷ α/s with dead time depending only on signal’s length;
2. gamma-detection module, which can handle count rates up to 10⁶ g/s per second from a BGO-based gamma-ray detector;
3. PC-controlled HV power supplies for photo multipliers used in gamma-ray detectors, for the position-sensitive associated particle detector;
4. single-board PC;
5. data transfer interface module;
6. system indicator module.

Examples of DAQ performance with a Ø63×63 mm³ BGO-based gamma-ray detector.

Dependence of the number of gamma-rays accepted by the DAQ on the counting rate of the gamma-ray detector.

Shift of the 4.43 MeV peak at different counting rates of the gamma-ray detector.

Dependence of the energy resolution of the gamma-ray detector for 664 keV and 4430 keV lines on the counting rate of the gamma-ray detector.

The specialized digital electronics and position-sensitive associated particles detector are now part of the SmartSENNA device.