“Warm liquid” detector for measuring dose profiles from ionizing radiation

The use of “warm liquid” tetramethylsilane (TMS) in ionization chambers for measuring dose profiles in water phantoms to prepare the accelerator for a proton therapy session is relevant. One of the promising areas of radiation therapy is proton therapy. To increase the conformality of proton therapy, it is important to know exactly the dose distributions from the energy release of the proton beam in the water phantom before conducting a proton therapy session. A television-type detector (TTD), which measures the profiles of the Bragg peak by the depth of the beam in the water phantom, helps to increase the accuracy of the dose distribution knowledge. To accurately determine the profile of the Bragg peak by the beam width in the water phantom, an additional method is proposed that will allow TTD to quickly determine the profile by the width of the Bragg peak in on-line mode. This prefix to the TTD will improve the quality of summing up the therapeutic beam-thanks to accurate knowledge of the profile by width, and therefore the formed high-dose distribution field will correspond to the irradiated volume in the patient and will increase the conformality of irradiation. The additional prefix to the TTD is designed on an organosilicon “warm liquid” and represents a high-precision ionization chamber with coordinate sensitivity along the width of the water phantom. The fully developed technology for obtaining “warm liquid” TMS allows creating both microdosimeters for proton therapy and detectors for measuring “dose profiles” in water phantoms during accelerator calibration. The considered prefix to the TTD detector - the calibrator meter of the dose field (KIDP) - can also be used independently of the TTD and with great accuracy measure the dose profiles of the Bragg peak in the water phantom, both in depth and width. KIDP can also be used to measure the outputs of secondary “instantaneous” neutrons and gamma quanta emitted from the water phantom orthogonally to the direction of the proton beam.

electronegative impurities, “warm liquids”, free electron yield, tetramethylsilane (TMS), liquid ionization chambers, Bragg peak profiles, television-type detector

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