Variations in relative biological effectiveness (RBE) from a fixed value of 1.1 are critical in proton beam therapy. To date, studies estimating RBE at multiple positions relative to the spread-out Bragg peak (SOBP) have been predominantly performed using passive scattering methods, and limited data are available for spot-scanning beams. Thus, to investigate the RBE of spot-scanning beams, Chin...

Fig 1: Comparison of the depth dose profiles of proton and photon beams. The photon dose falls off exponentially with depth (green curve). A mono-energetic proton beam is characteriled by the presence of the Bragg peak in the region where the protons stop (red profile). Through the superposition (blue curve) of many proton beams of different residual range it is possible to deposit a homogenous...

The aim of the study was to determine the relative biological effectiveness (RBE) of a 60-MeV proton radiotherapy beam at the Institute of Nuclear Physics, Polish Academy of Sciences (IFJ PAN) in Kraków, the first one to operate in Poland. RBE was assessed at the surviving fractions (SFs) of 0.01, 0.1, and 0.37, for normal human fibroblasts from three cancer patients. The cells were irradiated ...

Abstract A radiation-tolerant silicon carbide (SiC) based dosimeter was developed for the measurement of linear energy transfer (LET) distributions along Bragg curve pristine and spread-out peak (SOBP) clinical carbon beam. Since conventional ionized chamber is not suitable effective LET measurement, several energy-dispersive dosimeters are being tested in field. While most detector lacks radia...

There are few reports on the biological homogeneity within the spread-out Bragg peak (SOBP) of proton beams. Therefore, to evaluate the relative biological effectiveness (RBE) and the oxygen enhancement ratio (OER), human salivary gland tumor (HSG) cells were irradiated at the plateau position (position A) and three different positions within a 6-cm-wide SOBP (position B, 26 mm proximal to the ...

Emergency of Web services has promoted a new paradigm of a business process which is called the Service-Oriented Business Process (SOBP). The SOBP uses Web services as an implementation platform for activities that belong to a business process, and is modeled with a Business Process Definition Language (BPDL). A de facto standard of BPDLs is the Business Process Execution Language for Web Servi...

We investigated the relative biological effectiveness (RBE) of therapeutic proton beams at six proton facilities in Japan with respect to cell lethality of HSG cells. The RBE of treatments could be determined from experimental data. For this purpose, we used a cell survival assay to compare the cell-killing efficiency of proton beams. Among the five linear accelerator (LINAC) X-ray machines at ...

PURPOSE To obtain and assess the accuracy of 3D dose distributions and LET maps from a passively-scattered proton beam through the use of LET-dependent and LET-independent polymer gel formulations. METHODS Dose measurements were performed with BANG3-Pro2 (MGS Research, Inc, Madison, CT) polymer gel dosimeters. The dosimeters were mixed from kits and were poured into 14.5 cm high by 15 cm diam...

Charge particle therapy with 12 C ions has the advantage of an enhancement in physical dose distribution due to the Bragg Peak (BP) related to higher Relative Biological Effectiveness (RBE) with respect to X-ray radiotherapy and proton therapy (2.5 for 12 C ions and 1.1 for protons) [1], [2]. The RBE of a 12 C therapeutic beam changes dramatically with depth, especially towards the end of the S...

A simple analytical model is found that predicts the exact proton spectrum needed to obtain a spread-out-Bragg peak (SOBP) distribution for laser-accelerated proton beams. The theory is based on the solution to the Boltzmann kinetic equation for the proton distribution function. The resulting analytical expression allows one to calculate the SOBP proton energy spectra for the different beamlet ...