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The purpose of this study was to quantify actual patient organ doses from megavoltage computed tomography (MVCT) using an MVCT beam model of a helical tomotherapy unit in a general treatment planning system (TPS). Dosimetric parameters (percentage depth dose, lateral beam profile, and longitudinal beam profile) of the MVCT beam were measured using Gafchromic EBT3 films (ISP Corporation, Wayne, NJ, USA) and used for beam modeling in a Pinnacle3 TPS (Philips, Amsterdam, Netherlands); this TPS is widely used with linear accelerators. The created beam model was adjusted and validated by assessing point doses in a cylindrical phantom in static and helical beam plans with fine, normal and coarse pitches. Maximum doses delivered to important organs from MVCT delivery for five clinical cases were calculated using the created beam model. The difference (average ± one standard deviation for all evaluation points) between calculated and measured doses was -0.69 ± 1.20% in the static beam plan. In the helical beam plan, the differences were 1.83 ± 2.65%, 1.35 ± 5.94% and -0.66 ± 8.48% for fine, normal and coarse pitches, respectively. The average maximum additional dose to important organs from MVCT in clinical cases was 0.82% of the prescribed dose. In conclusion, we investigated a method for quantifying patient organ dose from MVCT delivery on helical tomotherapy using an MVCT beam model in a general TPS. This technique enables estimation of the patient-specific organ dose from MVCT delivery, without the need for additional equipment.

Three-alpha resonance states in 12C are investigated by using the method of analytic continuation in the coupling constant combined with the complex scaling method (ACCC+CSM). We obtain a broad 0+ resonance state with energy of Er = 1.66 MeV and width of Γ = 1.48 MeV, which has a similar structure as the second 0+ state.

To evaluate the dosimetric impact of respiratory breast motion and daily setup error on whole breast irradiation (WBI) using three irradiation techniques; conventional wedge (CW), field-in-field (FIF) and irregular surface compensator (ISC). WBI was planned for 16 breast cancer patients. The dose indices for evaluated clinical target volume (CTVevl), lung, and body were evaluated. For the anterior-posterior (AP) respiratory motion and setup error of a single fraction, the isocenter was moved according to a sine function, and the dose indices were averaged over one period. Furthermore, the dose indices were weighted according to setup error frequencies that have a normal distribution to model systematic and random setup error for the entire treatment course. In all irradiation techniques, AP movement has a significant impact on dose distribution. CTVevlD95 (the minimum relative dose that covers 95 % volume) and V95 (the relative volume receiving 95 % of the prescribed dose) were observed to significantly decrease from the original ISC plan when simulated for the entire treatment course. In contrast, the D95, V95 and dose homogeneity index did not significantly differ from those of the original plans for FIF and CW. With regard to lung dose, the effect of motion was very similar among all three techniques. The dosimetric impact of AP respiratory breast motion and setup error was largest for the ISC technique, and the second greatest effect was observed with the FIF technique. However, these variations are relatively small.

To study resonant and virtual states in a wide variety of nuclear systems, we develop the Jost function method (JFM) for treating systems having non-local potentials. In the case that the Pauli principle for nucleons between clusters is treated by applying the orthogonality condition model (OCM) to the JFM, the pseudo-potential of the OCM can be considered one of the non-local potentials. As examples to demonstrate the applicability of our method, we apply it to a 16O+α single-channel system and also a 9Li+n coupled-channel system. We also treat a 16O+n single-channel system with a knock-on exchange kernel to confirm that our method is applicable in more general cases having non-local potentials.