Radiation Protection Dosimetry Advance Access originally published online on October 15, 2008
Radiation Protection Dosimetry 2008 131(4):513-520; doi:10.1093/rpd/ncn251
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Characterisation of MCP-600D and MCP-700D thermoluminescence detectors and their applicability for photoneutron detection
1 Department of Radiotherapy and Radio-Oncology, Center for Oncology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
2 Institute for Experimental Physics, University Hamburg, Germany
* Corresponding author: e.brunckhorst{at}uke.uni-hamburg.de
Received May 30, 2008, amended September 9, 2008, accepted September 10, 2008
This paper presents the characteristics of two high-sensitive LiF:Mg,Cu,P thermoluminescence detectors (TLDs) named MCP-600D and MCP-700D [thermoluminescence detector (TLD) Poland]. Furthermore, the applicability of both detectors used as a paired system for photoneutron detection in a high-energy photon field at a linear accelerator is shown. For MCP-600D and MCP-700D, the batch homogeneity is within 22 and 14%, respectively (2 SD). Correction for the individual response of each TLD leads to a reproducibility of 5 and 4%, respectively Both TLD types reveal a linear detector response to dose up to 4 Gy. The energy dependence for both is within 2% for 4 and 6 MV photons. For a 15 MV photon beam, the MCP-600D shows a higher response (10%); compared with the MCP-700D (2%). The MCP-600D is capable of detecting extra doses due to photoneutrons in a 15 MV photon exposure; however, the signal for an open field of the used linear accelerator is in the order of the reproducibility. Using a kind of albedo technique allows detection of photoneutrons in the open photon field anyhow. The neutron detection limit is 10 µGy neutron dose per 1 Gy photon dose. Reproducibility of the TLDs, however, requires more than 10 detectors to determine results with an uncertainty of <5%.
In memoriam Rainer Schmidt