Neutron dosimetry and microdosimetry with track etch based LET spectrometer

There is still need to develop upgrade, and test further methods able to characterise the external exposure to neutrons. This contribution presents further results obtained with the goal to enlarge and upgrade the possibility of neutron dosimetry and microdosimetry with a LET spectrometer based on the chemically etched track detectors (TED). As TED we have used several types of polyallyldiglycolcarbonates (PADC). All were basically etched in 5 N NaOH. To determine the LET value of a particle, the etching rate ratio V (V=vT/vB; where vB is bulk etching rate and vT is track etching rate) is established through the determination of track parameters. They are measured by means of an automatic optical image analyzer LUCIA-NIS. The PADC detectors have been exposed in high-energy neutron beams at iThemba facility, Cape Town, South Africa, and in monoenergetic neutron beams at JRC Geel, Belgium, in neutron beams with energies from 0.2 to 19.5 MeV. LET spectra obtained are presented, the influence of PADC type's choice are analyzed and discussed. LET spectra obtained permit also to calculate the total dose and dose equivalent in a neutron beam. These data are also presented and compared with the references data submitted by facilities staff. (author)