Nanodosimetry and RBE values in radiotherapy.

In a recent paper, the authors reported that the dose mean lineal energy, [Formula: see text] in a volume of about 10-15 nm is approximately proportional to the α-parameter in the linear-quadratic relation used in fractionated radiotherapy in both low- and high-LET beams. This was concluded after analyses of reported radiation weighting factors, WisoE (clinical RBE values), and [Formula: see text] values in a large range of volumes. Usually, microdosimetry measurements in the nanometer range are difficult; therefore, model calculations become necessary.

Microdosimetry of proton and carbon ions.

Purpose: To investigate microdosimetry properties of 160 MeV/u protons and 290 MeV/u(12)C ion beams in small volumes of diameters 10-100 nm.

Methods: Energy distributions of primary particles and nuclear fragments in the beams were calculated from simulations with the general purpose code SHIELD-HIT, while energy depositions by monoenergetic ions in nanometer volumes were obtained from the event-by-event Monte Carlo track structure ion code PITS99 coupled with the electron track structure code KURBUC.

Results: The results are presented for frequencies of energy depositions in cylindrical targets of diameters 10-100 nm, dose distributions yd(y) in lineal energy y, and dose-mean lineal energies yD.

Evaluation of nuclear reaction cross-sections and fragment yields in carbon beams using the SHIELD-HIT Monte Carlo code. Comparison with experiments.

In light ion therapy, the knowledge of the spectra of both primary and secondary particles in the target volume is needed in order to accurately describe the treatment. The transport of ions in matter is complex and comprises both atomic and nuclear processes involving primary and secondary ions produced in the cascade of events. One of the critical issues in the simulation of ion transport is the modeling of inelastic nuclear reaction processes, in which projectile nuclei interact with target nuclei and give rise to nuclear fragments.

A Monte Carlo evaluation of carbon and lithium ions dose distributions in water.

Purpose: To compare dose distributions on the central- and off-axis for (12)C and (7)Li ion beams simulated by the codes SHIELD-HIT (Heavy Ion Transport) and FLUKA (FLUKtuierende KAskade), and compare with experimental data for 300 MeV/u (12)C and 185 MeV/u (7)Li ion beams.

Materials And Methods: The general purpose Monte Carlo codes, SHIELD-HIT10 and FLUKA 2008.3d.

Secondary absorbed doses from light ion irradiation in anthropomorphic phantoms representing an adult male and a 10 year old child.

Secondary organ absorbed doses were calculated by Monte Carlo simulations with the SHIELD-HIT07 code coupled with the mathematical anthropomorphic phantoms CHILD-HIT and ADAM-HIT. The simulated irradiations were performed with primary (1)H, (4)He, (7)Li, (12)C and (16)O ion beams in the energy range 100-400 MeV/u which were directly impinging on the phantoms, i.e.

Monte Carlo simulation of correction factors for IAEA TLD holders.

The IAEA standard thermoluminescent dosimeter (TLD) holder has been developed for the IAEA/WHO TLD postal dose program for audits of high-energy photon beams, and it is also employed by the ESTRO-QUALity assurance network (EQUAL) and several national TLD audit networks. Factors correcting for the influence of the holder on the TL signal under reference conditions have been calculated in the present work from Monte Carlo simulations with the PENELOPE code for (60)Co gamma-rays and 4, 6, 10, 15, 18 and 25 MV photon beams. The simulation results are around 0.