Results from the Commissioning of the n-TOF Spallation Neutron Source at CERN

The new neutron time-of-flight facility (n_TOF) has been built at CERN and is now operational. The facility is intended for the measurement of neutron induced cross sections of relevance to Accelerator Driven Systems (ADS) and to fundamental physics. Neutrons are produced by spallation of the 20 GeV/c proton beam, delivered by the Proton Synchrotron (PS), on a massive target of pure lead. A measuring station is placed at about 185 m from the neutron producing target, allowing high-resolution measurements. The facility was successfully commissioned with two campaigns of measurements, in Nov. 2000 and Apr. 2001. The main interest was concentrated in the physical parameters of the installation (neutron flux and resolution function), along with the target behavior and various safety-related aspects. These measurements confirmed the expectations from Monte Carlo simulations of the facility, thus allowing to initiate the foreseen physics program

High Spatial Resolution Fast-Neutron Imaging Detectors for Pulsed Fast-Neutron Transmission Spectroscopy

Two generations of a novel detector for high-resolution transmission imaging and spectrometry of fast-neutrons are presented. These devices are based on a hydrogenous fiber scintillator screen and single- or multiple-gated intensified camera systems (ICCD). This detector is designed for energy-selective neutron radiography with nanosecond-pulsed broad-energy (1 - 10 MeV) neutron beams. Utilizing the Time-of-Flight (TOF) method, such a detector is capable of simultaneously capturing several images, each at a different neutron energy (TOF). In addition, a gamma-ray image can also be simultaneously registered, allowing combined neutron/gamma inspection of objects. This permits combining the sensitivity of the fast-neutron resonance method to low-Z elements with that of gamma radiography to high-Z materials.Comment: Also published in JINST: http://www.iop.org/EJ/abstract/1748-0221/4/05/P0501

Response of CVD Diamond Detectors to 14 MeV Neutrons

A series of measurements was taken at the Physikalisch-Technische Bundesanstalt (PTB) Braunschweig [1] using the 14 MeV neutron beam at the Van der Graaf accelerator with chemical vapor deposition (CVD) diamond detectors, in preparation of an upcoming (n, ) cross-section measurement [2] at the CERN-n TOF experiment [3, 4]. A single-crystal (sCVD) as well as a poly-crystalline (pCVD) diamond detector were used for the measurements. The response of both materials to the mono-energetic neutron beam was studied, also with the prospect for future applications in plasma diagnostics for fusion research. The results of the measurements are presented in this report