Photon kerma determination using a high pressure graphite ionisation chamber in mixed fields of neutrons of energy 44 and 66 MeV
Natalia Golnik , H. J. Brede , U. J. Schrewe , Mieczysław Zielczyński
AbstractA high pressure C-CO2 ionisation chamber was used for the determination of the photon dose component in nearly monoenergetic neutron beams of energies of 44 MeV and 66 MeV. The chamber was operated at low voltages, i.e. under conditions of strong initial recombination in the tracks of the secondary charged particles. A new method of measurement was developed to extend the applicability of the graphite chamber as a 'neutron-insensitive' detector to an energy range in which the relative neutron sensitivity of the chamber, k(U), was not well known. It is shown that the photon karma can be estimated from ionisation current measurements performed at several collecting voltages applied to the electrodes of the chamber while the exact information on the spectral fluence of the neutron beam and the k(U) value of the chamber were not required. The measurement results were used to determine the k(U) values of the high pressure ionisation chamber for these neutron fields.
|Journal series||Radiation Protection Dosimetry, ISSN 0144-8420|
|Keywords in English||cross-sections; carbon; beams|
|ASJC Classification||; ; ; ;|
|Publication indicators||= 6; = 5; = 2.0; : 2000 = 0.742; : 2006 = 0.446 (2) - 2007=0.712 (5)|
|Citation count*||2 (2016-09-05)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.