A high-efficiency spin-resolved phototemission spectrometer combining time-of-flight spectroscopy with exchange-scattering polarimetry

A multi-stop time-of-flight spectrometer for the measurement of positron annihilation-induced electrons in coincidence with the Doppler-shifted annihilation gamma photon

Here we describe an advanced multi functional, variable-energy positron beam system capable of measuring the energies of multiple positron-induced electrons in coincidence with the Doppler-shifted gamma photon resulting from the annihilation of the correlated positron. The measurements were carried out using the unique characteristics of the digital time-of-flight spectrometer and the gamma spectrometer available with the advanced positron beam system. These measurements have resulted in (i) the first digital time of flight spectrum of positron annihilation-induced Auger electrons generated us…

CAMEA ESS - The Continuous Angle Multi-Energy Analysis Indirect Geometry Spectrometer for the European Spallation Source

The CAMEA ESS neutron spectrometer is designed to achieve a high detection efficiency in the horizontal scattering plane, and to maximize the use of the long pulse European Spallation Source. It is an indirect geometry time-of-flight spectrometer that uses crystal analysers to determine the final energy of neutrons scattered from the sample. Unlike other indirect gemeotry spectrometers CAMEA will use ten concentric arcs of analysers to analyse scattered neutrons at ten different final energies, which can be increased to 30 final energies by use of prismatic analysis. In this report we will out…

Automating Analysis of Neutron Scattering Time-of-Flight Single Crystal Phonon Data

This article introduces software called Phonon Explorer that implements a data mining workflow for large datasets of the neutron scattering function, S(Q, ω), measured on time-of-flight neutron spectrometers. This systematic approach takes advantage of all useful data contained in the dataset. It includes finding Brillouin zones where specific phonons have the highest scattering intensity, background subtraction, combining statistics in multiple Brillouin zones, and separating closely spaced phonon peaks. Using the software reduces the time needed to determine phonon dispersions, linewidths, a…

High energy neutron scattering from hydrogen using a direct geometry spectrometer

Deep inelastic neutron scattering experiments using indirect time-of-flight spectrometers have reported a smaller cross section for the hydrogen atom than expected from conventional scattering theory. Typically, at large momentum transfers, a deficit of 20-40% in the neutron scattering intensity has been measured and several theories have been developed to explain these results. We present a different approach to this problem by investigating the hydrogen cross section in polyethylene using the direct geometry time-of-flight spectrometer MARI with the incident energy fixed at a series of value…

采用门控前端质谱法精确报告HiPIMS过程中的离子飞行时间

Accurate Reporting of Ion Time-of-Flight during HiPIMS with Gated Front-End Mass Spectrometry

针对HiPIMS中离子飞行时间传统估算易产生非物理值的问题，提出门控前端质谱实验测量法，通过双极电源同步门控脉冲、接地屏蔽防干扰，实现多离子ToF精确测量并与理论计算对比验证。

The new Cold Neutron Chopper Spectrometer at the Spallation Neutron Source - Design and Performance

The design and performance of the new Cold Neutron Chopper Spectrometer (CNCS) at the Spallation Neutron Source in Oak Ridge are described. CNCS is a direct geometry inelastic time-of-flight spectrometer, designed to cover essentially the same energy and momentum transfer ranges as IN5 at ILL, LET at ISIS, DCS at NIST, TOFTOF at FRM2, AMATERAS at J-PARC, PHAROS at LANSCE and NEAT at HZB, at similar energy resolution. Measured values of key figures such as neutron flux at sample position and energy resolution are compared between measurements and ray tracing Monte Carlo simulations, and good ag…