Alpha Spectrometer α2

Application

Alpha Spectrometer is designed to transform alpha-particle energies into electrical signals, their amplification, filtration, and transformation into spectral lines and their acquisition for spectral analysis with determination of the intensities of spectral lines. Bench top alpha spectrometer α2 contains 2 measurement chambers, which allows for simultaneous analysis of up to two samples. Every Alpha spectrometer chamber includes alpha particle detector, pressure sensor and preamplifier of signals from alpha detector.

Features

The Silicon Ion Implanted Alpha Particle Detector is intended for precise alpha spectroscopy. The thin entrance window of the detectors provides good energy resolution even in close location of the alpha radioactive source and also provides high efficiency registration of alpha particles.

COMPLETE SET

Two alpha spectrometry chambers with preamplifiers, electronics, valves, etc.
Two alpha-particle detectors
Data acquisition and PC interface device
Built-in spectrometric device
Vacuum pump
SpectraLineADA analysis software
PC with emulation software
Documentation set

DESCRIPTION

Analytical software package allows to:

Execute spectra acquisition for the set time,
Mark and select regions of interest and examine them on a separate plane,
Increasing or reducing scale on horizontal and vertical axeis,
Perform energy calibration of spectra on two known energies;
Determine centroids and area of peaks with background deduction and without background deduction;
Make an estimation of energy resolution at one second and one tenth height of full absorption peak;
Carry out an automatic serial spectra acquisition with automatic record on a disk;
Print out spectrum window;
Compare different spectra in one window simultaneously reducing or decreasing scale;
Calculation of activities of alpha emitting radionuclides.

The activity calculation module uses the parametric model line of the alpha-spectrum. Spectrum of every alpha-emitted isotope line is represented by the combination of asymmetric Gauss distribution, exponent and hyperbola. These functions are combined using the conditions of the function and its first derivative continuity. This model represents alpha-spectra of both thin and thick sources, and gives good results with alpha-spectra measured by spectrometers with HPGe detectors and ionization chambers. The model parameters and activity values are specified using the minimum condition of the modified χ2- functional. The parameters of the spectrum deformation are varied. The deformation is caused by summing of alpha particles and conversion electrons impulses. The processing results are displayed and represented in a report view. The report pattern is specified by user. The fitting results are displayed on the spectrum graphics as nuclides independent spectra for visual control of the fitting results. The peak pattern after the minimization procedure can be saved and used for the spectrum analyses by the SpectraLine methods.
The detection efficiency calculation and label operations are realized.
The measured spectra and processing results can be saved to database.
This functionality enables to analyze the specified criterions convergence of the repeated measurements.

Specification

parameter	value
Energy range of detector operation, MeV	3 - 8
Instrumental background, cps/hour	< 2
Maximum input count rate, cps	> 10000
Detector sensitive area, mm2	450
Detector thickness, µm	400
Detector bias voltage, V	50
Energy resolution for 5.49 MeV, keV	< 20
Absolute detection efficiency at the distance of 5 mm from the sensitive area of the detector, %	> 20

Specification

parameter	value
Count rate	0-50 000 pulses/s
Shaping time constant, switchable	1 µs
Variable gain coarse and fine	Up to 500
Noise level (referred to the input)	< 3 mV for 2 µs
Pole-zero adjustment	Available
Live time correction	Available
Opportunity to operate with pulse feedback preamplifier	Available
Base line auto restoration	Available
Gain stability	< 0.0075 %/s
Integral nonlinearity	< 0.025 %