Search results for "dosimetrit"

Tietokonetomografian annosmittaukset : kalibrointikäytännöt ja epävarmuudet

2015

Tietokonetomografiassa säteilyannoksen määrittämiseen käytettävät ionisaatiokammiot kalibroidaan tavallisimmin vapaasti ilmassa suhteessa ilmakermaan. Kalibrointikäytännöistä voi kuitenkin aiheutua epävarmuutta annoksen määrittämiseen fantomimittauksissa, sillä olosuhteet fantomissa ovat erilaiset kuin vapaasti ilmassa. Tässä työssä tutkittiin kalibrointikäytännöistä johtuvia epävarmuuksia annosmittauksissa. Työn kokeellisessa osassa mitattiin erään puikkomaisen ionisaatiokammion energiavaste ja näiden tulosten pohjalta mallinnettiin kammio Monte Carlo -menetelmällä tehtäviä simulaatioita varten. Kammion mallintamisen jälkeen simulaatioissa tutkittiin absor…

Measurements of Low-Energy Protons using a Silicon Detector for Application to SEE Testing

2021

A silicon detector with a fast electronics chain is used for the dosimetry of protons in the range 0.5-5 MeV at the Centro Nacional de Aceleradores (CNA) 3 MV Tandem laboratory in Seville, Spain. In this configuration, measurements can be performed in pulsed mode, using a digitizer to record event-by-event proton energy depositions. The distributions of deposited energy were obtained thanks to a calibration with an alpha source. Measurements of flux and deposited energy are used to enable single event effect (SEE) testing on selected static random access memories (SRAMs).

Radioluminescence Response of Ce-, Cu-, and Gd-Doped Silica Glasses for Dosimetry of Pulsed Electron Beams

2021

Radiation-induced emission of doped sol-gel silica glass samples was investigated under a pulsed 20-MeV electron beam. The studied samples were drawn rods doped with cerium, copper, or gadolinium ions, which were connected to multimode pure-silica core fibers to transport the induced luminescence from the irradiation area to a signal readout system. The luminescence pulses in the samples induced by the electron bunches were studied as a function of deposited dose per electron bunch. All the investigated samples were found to have a linear response in terms of luminescence as a function of electron bunch sizes between 10−5 Gy/bunch and 1.5×10−2 Gy/bunch. The presented results show that these…

Properties of Gd-Doped Sol-Gel Silica Glass Radioluminescence under Electron Beams

2022

International audience; The radiation-induced emission (RIE) of Gd3+-doped sol–gel silica glass has been shown to have suitable properties for use in the dosimetry of beams of ionizing radiation in applications such as radiotherapy. Linear electron accelerators are commonly used as clinical radiotherapy beams, and in this paper, the RIE properties were investigated under electron irradiation. A monochromator setup was used to investigate the light properties in selected narrow wavelength regions, and a spectrometer setup was used to measure the optical emission spectra in various test configurations. The RIE output as a function of depth in acrylic was measured and compared with a reference…

Portaalidosimetrian käyttö sädehoitokiihdyttimen laadunvarmistuksessa

2009

Puolijohdediodit ulkoisen sädehoidon potilasannosmittauksissa

2008

Optical Fiber Based Dosimeter Data From RADEF Pulsed Electron Beams - Oscilloscope Traces

2021

These data are from tests of fiber optic based dosimetry systems. The purpose of the collected data is to use it for characterizing the different tested samples responses against pulsed electron radiation, for different electron bunch sizes. The tested samples are sol-gel silica glass rods doped with Ce, Cu, or Gd ions, making the rods radioluminescent. The samples were connected to a multimode pure-silica core optical fiber, which transported the radiation induced luminescence (RIL) to a photomultiplier tube (PMT) with an optical band pass filter in front of it. The samples were subject to a pulsed 20 MeV electron beam. The resulting output pulses from the PMT from the induced RIL light we…