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Neutron spectrometry in a PET cyclotron with a Bonner sphere system
F Fernández1, K Amgarou, C Domingo
1Grup de Física de les Radiacions. Departament de Física, Universitat Autónoma de Barcelona, E-08193 Bellaterra, Spain.
Radiation Protection Dosimetry
|June 19, 2007
Summary
This study measured neutrons produced by a cyclotron used for Positron Emission Tomography (PET) imaging. Neutron levels were assessed using Bonner sphere systems to ensure safety during radionuclide production.
Area of Science:
- Nuclear physics
- Medical imaging
- Radiation safety
Background:
- Positron Emission Tomography (PET) is a vital diagnostic tool.
- PET relies on short-lived radionuclides produced by cyclotrons.
- Cyclotron operation can generate potentially harmful neutrons.
Purpose of the Study:
- To evaluate neutron emissions from an unshielded cyclotron.
- To assess neutron levels at various locations within the cyclotron vault.
- To ensure radiation safety during radionuclide production for PET.
Main Methods:
- Utilized active and passive Bonner sphere systems for neutron detection.
- Conducted measurements inside and outside the cyclotron vault during operation.
- Employed an in-house unfolding code to determine neutron spectra.
Main Results:
- Quantified neutron measurements at different locations.
- Characterized the neutron spectrum at each measurement point.
- Provided data for evaluating and controlling neutron radiation.
Conclusions:
- Neutron measurements are crucial for cyclotron safety.
- Bonner sphere systems effectively assess neutron radiation.
- The study provides essential data for radiation protection in PET facilities.
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