INTRODUCTION A new type of personal dosimeter has been developed by RADOS Technology Oy. This system is based on a novel detector type, an ionisation chamber with so-called Direct Ion Storage (DIS). Ionisation chambers are sensitive to both neutrons and photons. Therefore, the application of the DIS principle to neutron dosimetry requires a double-chamber system for separating photon from neutr...

The characteristics of an Elekta Precise treatment machine with a gating interface were investigated. Three detectors were used: a Farmer ionisation chamber; a MatriXX ionisation chamber array and an in-house, single pulse-measurement ionisation chamber (IVC). Measurements were made of dosimetric accuracy, flatness and symmetry characteristics and duty cycle for a range of beam-on times and gat...

The primary standard for air kerma for the gamma radiation of Cs-137, of the Metrological Laboratory of Ionising Radiation (LMRI), is an ionisation chamber of the type CC01. This instrument was, for the first time, used to characterize the radiation field, in terms of air kerma, produced by a Cs-137 source in an irradiator Shepherd model 81, used mainly for radiation protection calibration purp...

OBJECTIVE To characterize a novel method for field-size quality assurance of a variable approximately circular aperture collimator by means of dose-area product measurements and to validate its practical use over two years of clinical application. METHODS   To assess methodical limitations, we analyze measurement errors due to change in linac output, beam tuning, uncertainty in MU delivery, d...

The difference in the relative biological efficiency (RBE) of ions of same linear energy transfer (LET) but different atomic number (Z) can be attributed to the difference in the radial ionisation distribution. We have performed systematic measurements of the spatial ionisation pattern of heavy ions of various Z but similar LET at GSI. The results are compared with track structure data obtained...

The SPARC-EBIT (fig.1) is an Electron Beam Ion Trap (from DREEBIT, Dresden) that will be used for tests and offline measurements, firstly for HITRAP, and later for SPARC (Stored Particle Atomic physics Research Collaboration). In the EBIT the ions are produced by electron impact ionisation of gas atoms by an intense electron beam. The magnetic field of a permanent magnet arrangement focuses the...

The aim of this study was to compare the high dose rate (HDR) iridium 192 source calibration in terms of reference air kerma rate with two types of ionisation chambers (a thimble chamber and a well-type chamber). Dose measurements in water have been also performed with thimble chamber and thermoluminescent dosimeters (TLD) in order to validate the absorbed dose to water calculation provided by ...

A direct comparison measurement of fluorescent nuclear track detectors (FNTDs) and a thimble ionisation chamber is presented. Irradiations were performed using monoenergetic protons (142.66 MeV, ϕ=3×10(6) cm(-2)) and carbon ions (270.55 MeV u(-1), ϕ=3 × 10(6) cm(-2)). It was found that absorbed dose to water values as determined by fluence measurements using FNTDs are, in case of protons, in go...