Author: Chaudhri, M.A.
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THOAB202 Secondary Neutron Production from Patients during Hadron Therapy and their Radiation Risks: the Other Side of Hadron Therapy 3118
  • M.A. Chaudhri
    University of Erlangen-Nuernberg, Erlangen, Germany
  We were the first to calculate and measure the neutron produced from patients during therapy with bremsstrahlung, and estimated their radiation doses *. This neutron output would be lot higher with hadrons due to their larger cross sections. There is no reliable/ useful data on this subject. Using the experimental neutron production data from different body elements, we have estimated the fluence and energies of these neutrons from tissue under irradiation with different hadrons. Our results indicate that at least 4.2 neutrons , with energies greater than 5 MeV, are produced for every C-ion of 400 MeV/u energy incident on tissue. This number reduces to 3, 1.4 and 0.3 respectively at C-energies of 300, 200 and 100 MeV /u. For protons these numbers are estimated to be 0.05, 0.2 and 0.4 per proton of energies 100, 200 and 300 MeV respectively. There would be even more neutrons with energies lesser than 5 MeV. The doses to some organs have been estimated, which are not negligible. A “Compromise optimum energy” concept is suggested. But extreme caution is highly recommend before treating patients with hadrons, especially children and younger people who still have many years to live.
* P.Allen and M.A Chaudhri, Phys. Med. Biol. 33 (1988) 1017
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