Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8177903 | Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | 2014 | 9 Pages |
Abstract
We studied the energy resolution of the pulsed neutron beam of the Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) at the Japan Proton Accelerator Research Complex/Materials and Life Science Experimental Facility (J-PARC/MLF). A simulation in the energy region from 0.7Â meV to 1Â MeV was performed and measurements were made at thermal (0.76â62Â meV) and epithermal energies (4.8â410Â eV). The neutron energy resolution of ANNRI determined by the time-of-flight technique depends on the time structure of the neutron pulse. We obtained the neutron energy resolution as a function of the neutron energy by the simulation in the two operation modes of the neutron source: double- and single-bunch modes. In double-bunch mode, the resolution deteriorates above about 10Â eV because the time structure of the neutron pulse splits into two peaks. The time structures at 13 energy points from measurements in the thermal energy region agree with those of the simulation. In the epithermal energy region, the time structures at 17 energy points were obtained from measurements and agree with those of the simulation. The FWHM values of the time structures by the simulation and measurements were found to be almost consistent. In the single-bunch mode, the energy resolution is better than about 1% between 1Â meV and 10Â keV at a neutron source operation of 17.5Â kW. These results confirm the energy resolution of the pulsed neutron beam produced by the ANNRI beamline.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Instrumentation
Authors
K. Kino, M. Furusaka, F. Hiraga, T. Kamiyama, Y. Kiyanagi, K. Furutaka, S. Goko, K.Y. Hara, H. Harada, M. Harada, K. Hirose, T. Kai, A. Kimura, T. Kin, F. Kitatani, M. Koizumi, F. Maekawa, S. Meigo, J. Hori,