Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
ST: Fachverband Strahlen- und Medizinphysik
ST 7: Radiation Physics Measurements
ST 7.3: Vortrag
Donnerstag, 17. März 2011, 16:30–16:45, POT 112
Calibration of tissue-equivalent proportional counters with the PTB neutron reference fields — •Johannes Rahm1,2, Joachim Breckow1, Oleksiy Burda2, Thorsten Klages2, Frank Langner2, and Frank Wissmann2 — 1Institut für medizinische Physik und Strahlenschutz, Fachhochschule Gießen-Friedberg, Wiesenstraße 14, 35390 Gießen — 2Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig
Dose determination in microdosimetric dimensions is essential for radiation protection, as well as for radiation biology and radiation therapy. Especially in mixed radiation fields with a large neutron component a tissue-equivalent proportional counter (TEPC) is an excellent instrument for dose measurement.
The TEPC response to neutrons was measured using the PTB neutron reference fields at energies of 0.606 MeV, 1.2 MeV, 8 MeV and 19 MeV. To determine dose and dose-equivalent microdosimetric spectra, a system with three gain stages was set up to cover a lineal energy range from 10−2 keV/µm up to 104 keV/µm. Two spherical TEPCs with a diameter of 2.24" were filled with a propane based tissue-equivalent gas mixture to simulate a tissue diameter of 2 µm and 4 µm, respectively. The aim of this work is to investigate the influence of different gas fillings and to obtain the response function of the TEPC with regard to monoenergetic neutron reference fields.