Radiation Protection Dosimetry 108:255-261 (2004)
Radiation Protection Dosimetry Vol. 108 No. 3 © Oxford University Press 2004; all rights reserved
Technical Note
Neutron measurements in the vicinity of a self-shielded pet cyclotron



1 Neely Nuclear Research Center, G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405, USA
2 Emory Center for PET, Room EG-46, Emory University Hospital, 1364 Clifton Road, NE, Atlanta, GA 30322, USA
* Corresponding author: nolan.hertel{at}me.gatech.edu
The radionuclides used in positron emission tomography (PET) are short-lived and generally must be produced on site using a cyclotron. A common end product of the nuclear reactions used to produce the PET radionuclides is neutron radiation. These neutrons could potentially contribute to the annual effective dose received by hospital personnel. A Bonner sphere spectrometer was used to measure neutron energy spectra at three locations near a self-shielded PET cyclotron. This cyclotron accelerates protons to 11 MeV. The neutron measurements reported were made during the production of 18F via the 18O(p,n)18F reaction (Q = 2.4 MeV). Neutron spectra were obtained with the BUMS unfolding code and converted to dose equivalent rates.