Quasi-differential scattering measurements were performed at the RPI Gaerttner Linear Accelerator (LINAC) Center with the High Energy Scattering (HES) System, which relies on the time-of-flight method to determine the incident neutron energy. The HES system relied on eight proton recoil fast neutron liquid scintillators detectors to collect neutron data. Each detector was optimized to measure...
To better understand the accuracy of current evaluated nuclear data, measurements of the neutron emission spectrum from the 181Ta, 19F, and 12C nuclei were conducted using the time-of-flight technique at the Gaerttner Linear Accelerator Laboratory at Rensselaer Polytechnic Institute. An array of eight EJ-301 organic liquid scintillator detectors coupled to photomultiplier tubes were used to...
The inelastic scattering of fast neutrons from
This process has technological implications in fusion and fission reactors. In the former it could create an intense
The ongoing enhanced interest in quantum entanglement, which can be actually regarded as photon scattering, is compared with the inclusion of internal level structures (resonances) of the nucleus and its impact on the scattering process and in particular on the angular distribution. The work covers the different approaches of the elastic and inelastic scattering in view of the fundamental...
In this talk we will present preliminary results associated to the neutron-induced inelastic channel on 40Ca. The data were measured at the GELINA neutron source of EC-JRC-Geel using the GAINS spectrometer. This is a HPGe-detector-based spectrometer that uses gamma spectroscopy coupled with the neutron time-of-flight technique to extract angle-integrated gamma-production cross sections for the...
The University of Kentucky Accelerator Laboratory has achieved ~1800 hours of beam-on-target since the last WINS meeting, and the research group has worked to upgrade our data acquisition and neutron/gamma-ray detection systems. Specifically, over the last year, angular distribution measurements of neutron elastic scattering on carbon-13 and neutron inelastic scattering on lithium-7 enriched...
The Gaerttner Linear Accelerator (LINAC) Center at Rensselaer Polytechnic Institute (RPI) utilizes its High Energy Scattering (HES) system to perform quasi-differential scattering measurements. This apparatus uses the time-of-flight (ToF) method for determining neutron energies and has a useful energy interval of 0.5 to 20 MeV. Monte Carlo simulations of the HES system are used in the...
The GAINS spectrometer, an integral part of the GELINA neutron source of EC-JRC Geel, has played a pivotal role in advancing neutron inelastic scattering measurements and contributing to significant scientific inputs. For more than 20 years, GAINS allowed us to perform very reliable and high precision neutron inelastic cross section measurements on various low-to-medium mass nuclei. This talk...
New measurements of the nucleon inelastic scattering cross sections was proposed in response to the concerns raised by the evaluators community with regard to the previous experiments, including our measurement published in 2014 [1].
The current experimental campaign includes a measurement of the proton inelastic scattering at the 9-MV Tandem accelerator of IFIN-HH, Romania and one of the...
The inelastic scattering of neutrons on 14N was investigated using the (n,n’g) technique. The g-production cross sections were measured at the GELINA (Geel Electron Linear Accelerator) neutron source of European Commission –Joint Research Centre. The radiation of interest was detected using the GAINS (Gamma Array for Inelastic Neutron Scattering) spectrometer, located on flight path 3, 100-m...
As the leading contributor to the total neutron cross section of nearly every nucleus, neutron scattering nuclear data are relevant for a wide variety of fundamental and applied fields of physics. While heavy element and actinide scattering cross sections are particularly poorly known, there exist major gaps in our understanding of cross sections and both neutron and
The ability for neutron transport methods to correctly represent the behavior of physical systems is directly related to the accuracy of the evaluated nuclear data. Most legacy differential and integral nuclear data measurements of high importance nuclei studied the total and radiative neutron capture cross sections to solve the neutron diffusion equation. Modern computational resources...
Multistep Direct (MSD) and Multistep Compound (MSC) mechanisms when combined account for emission of nucleons from a composite nucleus before it attains compound nucleus equilibrium. In spite being better founded than exciton model or other classical pre-equilibrium models, MSD and MSC were only occasionally employed in practical calculations. Initially, it was due to higher complexity of...
The Gaussian Orthogonal Ensemble (GOE) model for the compound nucleus reaction includes a random matrix in the scattering matrix, which allows us to evaluate average properties of fluctuating cross sections. The GOE model has been successfully applied to study the relation among the channel transmission coefficients, the decay width, and the cross section. It is a powerful tool when many...
Natural lead evaluations have been performed at RPI [1] to address concerns in deficient cross sections for fast spectrum applications [2]. As lead is a primarily scattering material, the quasi-differential scattering measurements done at RPI providea great basis for validating natural lead [3]. MCNP [4]simulations of the experiment with current lead evaluations[5] [6] [7] alluded to the...
GRAPhEME is a g-spectrometer developed by CNRS/IPHC Strasbourg (France), in collaboration with EC-JRC/Geel (Belgium) and IFIN-HH Bucharest (Romania). With its 6 High Purity Planar Germanium detectors, GRAPhEME, installed at the EC-JRC GELINA facility, was optimized for measurements of accurate (n,xn g) cross sections on actinides. The experimental methodology is based on prompt gamma-ray...
Active interrogation (AI) with neutrons is an important tool for nuclear security and nonproliferation applications, as well as for fossil fuel and space exploration. The backbone of this technique is a pattern of emitted gamma-rays which provide a distinct isotopic “fingerprint” of the material being interrogated. We aim to support AI by improving traditional and event-by-event simulation...
Neutron and γ-ray dual mode sensitivity is a widely utilized detector capability for nuclear security applications and fundamental nuclear physics measurements, such as neutron scattering and
To improve the accuracy of numerical simulations used in the development of nuclear reactors, over the past decade we studied (n, xn) reactions on tungsten isotopes. As this element, because of its physical and chemical properties, is widely used in modern nuclear reactors (and foreseen as a key component in fusion ones).
The IPHC group carried out an experimental program to measure (n, xn...
Quasi-differential neutron measurements performed at Rensselaer Polytechnic Institute with the high-energy scattering (HES) system have been used to collect energy-angle information from samples-of-interest. Data from those measurements were used with MCNP to validate various evaluated nuclear data libraries, such as ENDF/B-VIII.0 and JENDL-5. In addition to total quasi-differential...
The necessary improvement of evaluated nuclear data for nuclear applications development is possible through new and high quality experimental measurements.
In particular, improving (n, n') cross-section evaluations for faster neutrons than in current reactors is a goal of interest for new reactor fuels.
Our group at CNRS-IPHC has been running an experimental program to measure (n, n' γ)...
Neutron scattering reactions, specifically elastic scattering angular distributions, are an often neglected aspect of nuclear data evaluations. Difficulties in representing scattering distributions from both theoretical as well as formatting perspective and a lack of validating experiments leaves a largely unconstrained physics space that has proven to contribute significantly to critical...
