ASTRA (Adaptierter Schwimmbecken-Typ-Reaktor Austria, english translation: Adapted swimming pool-type reactor Austria) was a type of nuclear research reactor built in Seibersdorf, Austria near Vienna, at the site of the former Austrian Reactor Center Seibersdorf which now forms part of the Austrian Institute of Technology (AIT). ASTRA operated from 1960 to 1999.
Timeline
editSeptember 1960 | 100kW (initial criticality) |
May 1962 | 1MW |
August 1962 | 5MW |
August 1969 | 6MW |
1972 | 7MW |
January 1975 | 8MW |
~1989 | 9.5MW |
1999 | decommissioned |
Research
editOne of the most advanced experiments in physics carried out at the ASTRA reactor was an experiment on the decay of free neutrons.[1] In this experiment, the electron-neutrino angular correlation in free neutron decay was measured via the shape of the energy spectrum of the recoil protons; the center of a highly evacuated tangential beam tube of the reactor served as neutron source.
The aim was to determine the ratio of the two coupling constants gA and gV of the weak interaction from the shape of the recoil proton spectrum. This spectrum was measured using an electrostatic spectrometer; the protons were counted using an ion electron converter of the coincidence type.
The result was[2] |gA/gV| = 1.259 ± 0.017. This is in good agreement with the later (much more accurate) average[3] gA/gV = - 1.2695 ± 0.0029; this value was measured using polarised neutrons and hence contains also the sign of the ratio.
Literature
edit- R. Dobrozemsky: Production of a Clean Neutron Gas for Decay and Scattering Experiments. In: Nuclear Instruments and Methods. 118 (1974) 1–37.
References
edit- ^ Dobrozemsky, R.; Kerschbaum, E.; Moraw, G.; Paul, H.; Stratowa, C.; Weinzierl, P. (1975-02-01). "Electron-neutrino angular correlation coefficientameasured from free-neutron decay". Physical Review D. 11 (3). American Physical Society (APS): 510–512. Bibcode:1975PhRvD..11..510D. doi:10.1103/physrevd.11.510. ISSN 0556-2821.
- ^ Stratowa, Chr.; Dobrozemsky, R.; Weinzierl, P. (1978-12-01). "Ratio derived from the proton spectrum in free-neutron decay". Physical Review D. 18 (11). American Physical Society (APS): 3970–3979. doi:10.1103/physrevd.18.3970. ISSN 0556-2821.
- ^ Beringer, J.; Arguin, J. -F.; Barnett, R. M.; Copic, K.; Dahl, O.; et al. (Particle Data Group) (2012-07-20). "Review of Particle Physics". Physical Review D. 86 (1). American Physical Society (APS): 0100001. Bibcode:2012PhRvD..86a0001B. doi:10.1103/physrevd.86.010001. hdl:10481/34377. ISSN 1550-7998.
External links
edit- Announcement of planned shutdown from ARC
- Planning for the Decommissioning of the ASTRA-Reactor, an IRPA paper from ARC (PDF)
- 2001 European Commission legal opinion concerning the disposal of nuclear waste from decommissioning ASTRA