Application for nuclear sample mesurements
-
Beta and Beta/Gamma spectrometry systems for sample measurements.
-
As central E-detectors for spectrometry plastic scintillators but also NaI & HPGe detectors can be used, both for simultaneous gamma spectrometry also.
-
In combination with a high beta-sensitive thin plastic scintillator or gas detector used as dE-detector for very high beta separation.
For National and international organizations and companies in
-
Environmental, health and food surveillance and laboratories
-
Universities, research centers, nuclear medicine
-
Industry- and nuclear technology
-
Dismantling, consulting, waste management
-
Civil defense, emergency response, border, safety, security and access control
Beta Spectrometry Systems
Important Highlights:
Selectivity
-
Using one of the ISuS dE-detectors where beta particles can be separated perfectly from photons.
-
Separation factors of more than 1000 are realizable
Efficiency
-
Related to a 2π-source emission geometry using a Sr/Y-90 source in equilibrium up to 50 % efficiency.
Lower Limit of Detection (LLD)
-
Depends on the selected detection system, the source geometry & sample preparation and the nuclide matrix in the sample. LLD's down to 3 mBq/g sample weight are attainable.
Example for dE Detectors:
-
Gas flow -detector (standard: Methane, or other Gas)
-
Geometry: about 16 mm thick, ~ 70 or 120 mm sensitive inner diameter, Outer diameter: 98 as well as 160 mm
-
Type: Transmission-Detector
-
Beta-sensitivity: down to about 50 keV
-
Beta/Gamma Separation Power: about 1000
-
Very thin plastic scintillator detector (< 1 mm) with large surface
Substantial Advantages
Using point sources, filter samples or thin Petrie-shells with as lower self-absorption as possible
-
no chemical sample preparation is necessary
-
the filters sample can be used close on a detector endcap,
-
for liquids sources mostly an evaporation is sufficient
Beta and/or photon spectra can be detemined depedent from the system configuration.
Pure Beta-Spectra
The linear spectra show the perfect beta distributions of 3 Sr/Y-90 filter samples (down to 10 mBq) measured with a plastic scintillation detector system. The low energy Sr-90 and the high energy Y-90 distribution is shown in the spectra and can be separated.
above:
-
128 mBq (pink)
-
50 mBq (magenta)
-
10 mBq (red)
-
background (black)
and down:
with background subtraction
Sr/Y-90 source measured with a HPGe decetor without lead shield (black) and in beta-coincidence with a gas detector direct in front of the HPGe endcap (red). It shows the pure beta-distribution (red) through the perfect beta selection of the gas detector in log-mode.
TIME IS MONEY!
Determine the lowest level Beta/Gamma-Activities with minimum of sample preparation “simultaneously” by Beta- and Photon-Spectrometry
