| Zugriffsnummer | 29328 |
| Dokumenttyp | Bericht |
| Sprache | Englisch |
| Titel | High-energy quasi-monoenergetic neutron fields: existing facilities and future needs |
| Autor(in); Institution |
Pomp, S.; Uppsala University, Uppsala, SWEDEN
Bartlett, D. T.; Abingdon, Oxfordshire, UK
Mayer, S.; Paul Scherrer Institute, Villigen, SWITZERLAND
Reitz, G.; Deutsches Zentrum für Luft- und Raumfahrt, Cologne, GERMANY
Röttger, Stefan; 6.4, Ionenbeschleuniger und Referenzstrahlungsfelder, PTB-Braunschweig
Silari, M.; CERN, Geneva, SWITZERLAND
Smit, F. D.; iThemba Laboratory for Accelerator Based Sciences, Somerset West, SOUTH AFRICA
Vincke, H.; CERN, Geneva, SWITZERLAND
Yasuda, H.; UNSCEAR Secretariat, Vienna, AUSTRIA
|
| Quelle/Jahr | (2013), IV, 37 S. |
| Schriftenreihe | EURADOS Report: 2013-02 |
| ISBN | 978-3-943701-04-3 |
| URL | |
| Berichtsnummer | EURADOS Report 2013-02 |
| Verlag | Braunschweig: European Radiation Dosimetry Group e. V. |
| Zusammenfassung | High-energy neutrons are the dominant component of the prompt radiation field present outside the shielding of high-energy accelerators, and are a significant component of the cosmic radiation fields in aircraft and in spacecraft. In radiotherapy using high-energy medical accelerators, high-energy neutrons are a secondary component of the fields in the beam delivery system and in the patient’s body. The range of neutron energies in these fields extends from thermal energies to several GeV, and the energy distributions of energy fluence generally have several regions of greater intensity: at thermal energies, at around 1 MeV – 2 MeV (the evaporation peak), at around 100 MeV – 200 MeV (the quasi-elastic peak), and near the maximum incident particle energy. There is greater concern about high-energy neutron fields owing to the increasing number of high-energy accelerators in research and medicine and the special consideration given to the occupational exposure to cosmic radiation. In order to study the physics of neutron interactions in these applications, in particular concerning dosimetry, radiation protection monitoring of workplaces, and radiation effects in electronics, particularly those used in aircraft and in spacecraft, well-characterized neutron fields for high energies are needed. In the present Report, EURADOS working group 11 presents the argument that well-characterized quasi-monoenergetic neutron (QMN) sources reaching into the energy domain above 20 MeV are needed. We present an overview of the existing facilities, discuss their advantages and disadvantages, and present a list of key factors that an ideal QMN source for dosimetry and spectrometry should offer. Two simulated high energy reference fields are also described. The Report concludes that, out of the worldwide six QMN facilities currently in existence, all operate in sub-optimal conditions for dosimetry. Of the three facilities in Japan, one is at least temporarily out of action, and the only currently available QMN facility in Europe capable of operating at energies above 40 MeV, TSL in Uppsala Sweden, is threatened with shutdown in the immediate future. In Europe, a facility, NFS at GANIL, France, is currently under construction. NFS could deliver QMN beams up to about 30 MeV. It is, however, so far not clear if and when NFS will be able to offer QMN beams or operate with only so-called white neutron beams. It is likely that in about five years, QMN beams with energies above 40 MeV will be available only in South Africa and Japan, with none in Europe. |
Zitierung
Pomp, S., Bartlett, D. T., Mayer, S., Reitz, G., Röttger, S., Silari, M., Smit, F. D., Vincke, H., & Yasuda, H. (2013). High-energy quasi-monoenergetic neutron fields: existing facilities and future needs (Report No. EURADOS Report 2013-02). Braunschweig: European Radiation Dosimetry Group e. V.