Linac ^natW target close-in geometry photoneutron study by nuclear track distribution function

Area of Science:

• Nuclear physics
• Medical physics
• Radiotherapy

Background:

• Photonuclear reactions in tungsten (W) targets generate neutron yields during electron beam stopping.
• Neutron radiation poses side effects in tumor or cancer radiotherapy.
• Optimizing neutron energy spectrum is crucial for effective radiotherapy.

Purpose of the Study:

• To assess a proposed close-in irradiation geometry for improved radiotherapy effectiveness.
• To evaluate the reduction of neutron radiation fields.
• To investigate photoneutron yield and energy spectrum.

Main Methods:

• Monte Carlo simulations were used to assess the experimental arrangement.
• Nuclear track-etch methodology with poly allyl di-glicol carbonate polymer detectors was employed.
• Boron (98%) converter and cadmium filter were used to determine thermal and epithermal photoneutron yields.

Main Results:

• The study determined photoneutron yields for thermal and epithermal energy groups.
• Etched track diameter histograms, analyzed by distribution functions, provided the ratio of thermal to higher energy neutrons.
• The proposed geometry's convenience and effectiveness in managing neutron fields were assessed.

Conclusions:

• The close-in irradiation geometry shows promise for enhancing radiotherapy effectiveness.
• Understanding neutron yield and energy spectrum is vital for optimizing dose delivery.
• This research offers new insights into therapy beam quality and radiotherapy dose delivery.