The use of small fields in radiotherapy presents some difficulties, such as dosimeters limited dimension and the absence of lateral electronic equilibrium. The high dose used makes the control and accuracy of these process being precisely assured. Among the techniques used in dosimetry there is the electron magnetic resonance (EMR) in conjunction with radiation sensitive materials. EMR spectroscopy can detect unpaired electrons which may be originated from the interaction of ionizing radiation with matter. By changing the spectrometer cavity, such as with the use of a loop-gap resonator, the sensitivity of the technique is improved, increasing the detection for small sample sizes or with small amount of material. Among the new materials used is 2-methyl-alanine and lithium formate, showing superior sensitivity than the widely recognized alanine dosimeter, efficient for low doses dosimetry (low number of spins generated by radiation) or with small dosimeter dimensions and high doses dosimetry, which have not been much explored, requiring a deeper study and characterization of these materials. To complement, computer codes are capable of simulating physical interactions in complex systems, facilitating the verification and comparison between theoretical and experimental results. Thus, this project aims the production and characterization of small 2-methyl-alanine and lithium formate dosimeters designed for small fields dosimetry in conjunction with the EMR and computer simulations obtained by Monte Carlo method.
News published in Agência FAPESP Newsletter about the scholarship: