PURPOSE To obtain the absolute dose-rate distribution in liquid water for all six cup-shaped Leipzig applicators by means of an experimentally validated Monte Carlo (MC) code. These six applicators were used in high-dose-rate (HDR) afterloaders with the "classic" and v2 (192)Ir sources. The applicators have an inner diameter of 1, 2, and 3 cm, with the source traveling parallel or perpendicular...

Currently, the use of blood irradiation for inactivating pathogenic microbes in infected blood products and preventing graft-versus-host disease (GVHD) in immune suppressed patients is greater than ever before. In these systems, dose distribution and uniformity are two important concepts that should be checked. In this study, dosimetry of the gamma chamber blood irradiator model Gammacell 3000 ...

Calibrations of an HPGe detector were made with respect to photon energy and angle of incidence for the use in field gamma spectrometry. The same detector was modelled in MCNP4C and simulated. This revealed some significant differences between the theoretical (simulated) efficiency and the measured efficiency of the detector, especially at lower energies. In order to investigate the reason for ...

The generation of nodal cross sections and equivalence parameters for prismatic VHTR core components is discussed. For fuel-block cross section generation, a conventional single-block model with a reflective boundary condition is used. A one-dimensional fuel-reflector model is proposed for reflector cross section generation in order to accurately represent the significant neutron spectrum varia...

This paper presents a new assembly-level Monte Carlo neutron transport code, specifically intended for diffusion code group-constant generation and other reactor physics calculations. The code is being developed at the Technical Research Centre of Finland (VTT), under the working title “Probabilistic Scattering Game”, or PSG. The PSG code uses a method known as Woodcock tracking to simulate neu...

Twoand three-dimensional numerical benchmark cases based on the Compact Nuclear Power Source (CNPS) experiments conducted at the Los Alamos National Laboratory (LANL) in the 1980s have been specified for the validation and verification of Very High Temperature Reactor (VHTR) physics codes. Previous evaluation of the CNPS experiments has shown that the experimental tests could be useful for the ...

Full buildup diodes can cause significant dose perturbation if they are used on most or all of radiotherapy fractions. Given the importance of frequent in vivo measurements in complex treatments, using thin buildup (low-perturbation) diodes instead is gathering interest. However, such diodes are strictly unsuitable for high-energy photons; therefore, their use requires evaluation and careful me...

Monte Carlo (MC) method is the most accurate method for dose calculations in radiotherapy. It has been used in many applications including external photon and electron beam therapy, brachytherapy, etc. (1). MC method has overcome the deficiencies of analytical dose calculation methods in conditions such as tissue inhomogeneities and electronic disequilibrium with small fields(2-5). For the appl...