Real-Time Magnetic Electron Energy Spectrometer for Use With Medical Linear Acceletors

Paul Maggi, Robert Carver, Kenneth Hogstrom, Kenneth Matthews II, White, Marion (Ed.), Schaa, Volker RW (Ed.), Power, Maria (Ed.), Shiltsev, Vladimir (Ed.)
2017
Accelerator characterization and quality assurance is an integral part of electron linear accelerator (linac) use in a medical setting. The current clinical method for radia-tion metrology of electron beams (dose on central axis versus depth in water) only provides a surrogate for the underlying performance of the accelerator and does not provide direct information about the electron energy spectrum. We have developed an easy to use real-time magnetic electron energy spectrometer for
more » ... eter for characterizing the electron beams of medical linacs. Our spectrometer uses a 0.57 T permanent magnet block as the dispersive element and scintillating fibers coupled to a CCD camera as the position sensitive detector. The goal is to have a device capable of 0.12 MeV energy resolution (which corresponds to a range shift of 0.5 mm) with a minimum readout rate of 1 Hz, over an energy range of 5 to 25 MeV. This work describes the real-time spectrometer system, the detector response model, and the spectrum unfolding method. Measured energy spectra from multi-ple electron beams from an Elekta Infinity Linac are presented.
doi:10.18429/jacow-napac2016-tupoa38 fatcat:5urnv7edtve5lcfsttogk34awu