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Scattering experiments performed with the Rensselaer Polytechnic Institute Linear Accelerator measured elastic and inelastic scattering from an elemental iron sample. Eight liquid scintillator (EJ-301) proton recoil fast neutron detectors were positioned at several angles 0.5 m from the scattering sample. Data were measured using neutron time-of-flight in the energy range from 0.5 to 20 MeV, and pulse shape analysis was used to discriminate neutrons from gamma-rays. Nuclear data evaluations were compared to experimental data using Monte Carlo calculations. Below 2 MeV two new techniques were developed: a method which assessed inelastic-to-elastic scattering ratios and a method to determine the contribution from neutrons after only elastic scattering. These techniques, along with time-of-flight results, may help identify specific reactions that account for differences between evaluations and experimental data.

The neutron microscopic capture cross section for 235U is a critical parameter for the design and operation of nuclear reactors. The evaluated nuclear data libraries of ENDF/B-VII.1 and JENDL-4.0 h...

High-energy-neutron-scattering experiments for elemental zirconium were performed at the electron linear accelerator facility at Rensselaer Polytechnic Institute. The scattering experiments were pe...

The Gaerttner Laboratory electron linear accelerator at Rensselaer Polytechnic Institute was used in the measurement of the neutron total cross section of natural beryllium and carbon (graphite) in...

A series of new total cross section measurements for the stable molybdenum isotopes of 92,94,95,96,98,100 Mo covering the energy range between 1 keV and 620 keV was performed at the Gaerttner LINAC Center at Rensselaer Polytechnic Institute. New high-accuracy resonance parameters were extracted from an analysis of the data using the multilevel R-matrix Bayesian code SAMMY. In the unresolved resonance region, average resonance parameters and fits to the total cross sections were obtained using the Bayesian Hauser-Feshbach statistical model code FITACS.

In order to aid in the improvement of the high energy neutron differential scattering cross-section data, scattering experiments were performed using a collimated source of pulsed neutrons with energies up to 20 MeV from the Rensselaer Polytechnic Institute Linear Accelerator. An array of proton recoil detectors surrounding a sample placed at 30.1 m from the source measures the scattered flux using time-of-flight (TOF) methods. A state of the art digital data acquisition system is used to collect the data from the detector array and stream the digitized data to disk. Software was developed to perform pulse shape analysis, multi-channel analyzer functions, and to generate TOF spectra and angular dependent scattered neutron distributions. Scattering measurements were performed on carbon and molybdenum and compared to the Monte Carlo simulation using various nuclear data libraries.

Accurate isotopic molybdenum nuclear data are important because molybdenum can exist in nuclear reactor components including fuel, cladding, or as a high yield fission product. High-resolution time-of-flight neutron transmission measurements on highly enriched isotopic metallic samples of $^{95}\mathrm{Mo}$, $^{96}\mathrm{Mo}$, $^{98}\mathrm{Mo}$, and $^{100}\mathrm{Mo}$ were performed in the resonance energy range from 1 to $620\phantom{\rule{0.16em}{0ex}}\mathrm{keV}$. The measurements were taken with the newly developed modular $^{6}\mathrm{Li}$-glass transmission detector positioned at the 100-m experimental flight station. In the unresolved energy region (URR), new comprehensive methods of analysis were developed and validated in order to obtain accurate neutron total cross-section data from the measurement by correcting for background and transmission enhancement effects. Average parameters and fits to the total cross section for $^{95}\mathrm{Mo}$ were obtained using the Hauser-Feshbach statistical model code fitacs, which is currently incorporated into the sammy code. The fits to the experimental data deviate from the current evaluated nuclear data file/B-VII.1 isotopic Mo evaluations by several percent in the URR.

The nuclear data program at the Rensselaer Polytechnic Institute (RPI) is centered around a 60 MeV pulsed electron Linear Accelerator (LINAC) configured to deliver pulsed neutron beams. The LINAC electron pulse width can vary between 5 ns and 5 us, a repetition rate of 1–500 pulses per second and neutron yield of up to 1013 n/s. Over the years several experimental setups and techniques were developed to enable a variety of measurement capabilities. The experiments cover the energy range from 0.001 eV to 20 MeV and included neutron transmission, capture, scattering and fission measurements. The facility is also equipped with a Lead Slowing-Down Spectrometer (LSDS) producing a high neutron flux that is used for simultaneous measurements of the fission cross section and fission fragment mass and energy distributions. Detectors for (n, alpha) and (n, p) cross section measurements using the LSDS were also developed and measurements of (n, alpha) cross section were completed. The high neutron flux inside the LSDS enables measurements on small samples (sub micrograms) or samples with small cross section (sub millibarns). In order to fully utilize the capabilities of the facility, several measurement techniques were developed; high accuracy (