The accurate determination of neutraon cross-sections as a function of the neutron energy at a time-of-flight facility requires a precise knowledge of the time-energy relation far the neutraon beam. For the n_TOF neutron beam at CERN, produced by spallation of high-energy protons on a Pb target, the time-energy relation is connected to the production mechanism and to the subsequent moderation process. A calibration of the neutraon energy scale is proposed based on detailed Monte Carlo simulations of the facility. This time-energy relation has been experimentally validated by means of dedicated measurements of standard energy resonances, from l eV to approximately 1 MeV. On the basis of the present measurements, it is proposed to correct the energy of the 1.3 eV resonance of 193-Ir, which is commonly considered as an energy standard.
Time-Energy Relation of the n_TOF Neutron Beam: Energy Standards Revisited
Ventura, A.;Mengoni, A.
2004-10-01
Abstract
The accurate determination of neutraon cross-sections as a function of the neutron energy at a time-of-flight facility requires a precise knowledge of the time-energy relation far the neutraon beam. For the n_TOF neutron beam at CERN, produced by spallation of high-energy protons on a Pb target, the time-energy relation is connected to the production mechanism and to the subsequent moderation process. A calibration of the neutraon energy scale is proposed based on detailed Monte Carlo simulations of the facility. This time-energy relation has been experimentally validated by means of dedicated measurements of standard energy resonances, from l eV to approximately 1 MeV. On the basis of the present measurements, it is proposed to correct the energy of the 1.3 eV resonance of 193-Ir, which is commonly considered as an energy standard.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
