Abstract:
:Currently, energy spectra of laser accelerated proton beams are far from being monoenergetic. For their application in radiation therapy, energy selection systems using magnetic fields have been proposed to single out particles with the desired energy. These systems allow the choice of protons between a lowest and a highest energy. In this work, we present a slight modification that allows us to influence the relative number of particles per energy bin. In fact, the transmitted spectrum can be shaped in such a way that it corresponds to a full spread out Bragg peak delivered simultaneously. This change of the spectrum can be achieved by inserting suitably formed scattering material at the central plane of the energy selection system where the particles are separated in space depending on their energy. With the help of Monte Carlo simulations we analysed both simple wedge geometries and various stacks of lead slices. We found that these configurations can provide energy spectra that naturally produce spread out Bragg peaks within one laser shot. This increases the particle efficiency of the whole system and makes laser accelerated protons more suitable for radiation therapy.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Schell S,Wilkens JJdoi
10.1088/0031-9155/54/19/N04subject
Has Abstractpub_date
2009-10-07 00:00:00pages
N459-66issue
19eissn
0031-9155issn
1361-6560pii
S0031-9155(09)20679-8journal_volume
54pub_type
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