A neutron spectrometer was acquired for use in the measurement of National Institute of Standards and Technology neutron fields. The spectrometer included options for the measurement of low and high energy neutrons, for a total measurement range from 0.01 eV up to 17 MeV. The spectrometer was evaluated in calibration fields and was used to determine the neutron spectrum of an Americium-Berylliu...

The root-mean-square radius for neutrons in nuclei is investigated in the Skyrme Hartree-Fock model. The main source of theoretical variation comes from the exchange part of the density-dependent interaction which can be related to a basic property of the neutron equation of state. A precise measurement of the neutron radius in 208Pb would place an important new constraint on the equation of st...

The primary nature of the C neutron source is very significant for the studies of the s-process nucleosynthesis. In this paper we present an attempt to fit the element abundances observed in 16 s-rich stars using parametric model of the single neutron exposure. The calculated results indicate that almost all s-elements were made in a single neutron exposure for 9 sample stars. Although a large ...

In this document I consider the performance of a long pulse spallation source for those neutron scattering experiments that are usually performed with a monochromatic beam at a continuous wave (CW) source such as a nuclear reactor [ 11. This class of expeijments can be represented generically by the upper part of Figure 1. A monochromatic neutron beam with wavevector ki falls on a sample and th...

After almost 2.5 years of actively accreting, the neutron star X-ray transient and eclipsing binary MXB 1659–29 returned to quiescence in 2001 September. We report on a Chandra observation of this source taken a little over a month after this transition. The source was detected at an unabsorbed 0.5–10 keV flux of only (2.7 − 3.6) × 10 erg cm s, which implies a 0.5–10 keV X-ray luminosity of app...

The proposed Spallation Neutron Source (SNS) is an accelerator-based 1 – 2 MW pulsed neutron source to be built in Oak Ridge, Tennessee. The facility has five major sectionsó a "front end" consisting of a 65 Kev H ion source followed by a 2.5 MeV RFQ; a 1 GeV linac; a storage ring; a 1 MW spallation neutron target; and the conventional facilities to support these machines. These components will...

A 14-MeV neutron source based on a Gas-Dynamic Trap will provide a high flux of 14 MeV neutrons for fusion materials and sub-component testing. In addition to its main goal, the source has potential applications in condensed matter physics and biophysics. In this report, the author considers adding one more capability to the GDT-based neutron source, the modulation of the neutron flux with a de...