【摘 要】
：
The Back-n white neutron source (known as Back-n) is based on back-streaming neutrons from the spal-lation target at the China Spallation Neutron Source (CSNS).With its excellent beam properties,e.g.,a neutron flux of approximately 1.8×107 n/cm2/s at 55 m
【机 构】
：
State Key Laboratory of Particle Detection and Electronics;Institute of High Energy Physics,Chinese
论文部分内容阅读
The Back-n white neutron source (known as Back-n) is based on back-streaming neutrons from the spal-lation target at the China Spallation Neutron Source (CSNS).With its excellent beam properties,e.g.,a neutron flux of approximately 1.8×107 n/cm2/s at 55 m from the spallation target,energy range spanning from 0.5 eV to 200 MeV,and time-of-flight resolution of a few per thousand,along with the equipped physical spectrometers,Back-n is considered to be among the best facilities in the world for carrying out nuclear data measurements.Since its comple-tion and commencement of operation in May 2018,five types of cross-section measurements concerning neutron capture cross-sections,fission cross-sections,total cross-sections,light charged particle emissions,in-beam gamma spectra,and more than forty nuclides have been measured.This article presents an overview of the experimental setup and result analysis on the neutron-induced cross-section measurements and gamma spectroscopy at Back-n in the initial years.
其他文献
建立了使用高温氦气逆流方式加热的管式活塞流碘化氢(HI)分解膜反应器数学模型,利用有限时间热力学理论和最优控制理论以总熵产率(EGR)最小为目标求解了反应器的最优构型,最优反应器的总熵产率相比参考反应器降低了15.8％.在改变氦气入口流率的情况下,设计了总熵产率与最优反应器相同的加长反应器.结果 表明,两种优化后反应器总熵产率的减少主要是传热过程的不可逆性降低引起的,最优反应器局部熵产率分布更均匀.
本文将地埋管储热和水箱储热相耦合,组合成了新型地下跨季节复合储热系统,结合实验研究和数值计算的方法开展了热扩散机理与储/释热特性的研究.结果表明,储热阶段,地埋管储热起到“热屏”作用,抑制了水箱储热模式的热量向外围扩散;释热阶段,水箱储热有效回收了地埋管储热释放到土壤中的热量,增大了释热量.并结合热储存率和利用率定量分析了热量扩散程度,复合储热模式的热储存率和利用率均高于传统水箱储热模式和地埋管储热模式,热量得到了更高效的储存和再利用,其中复合储热模式效率为67.29％,水箱储热模式和地埋管储热模式分别为
In this study,the non-trival effect of the selection of reference particles for decay angle definitions is demonstrated when constructing the partial-wave amplitude of multi-body decays using helicity formalism.This is-sue is often ignored in the standard
空气源热泵以其方便灵活、高效环保的特点得到了较为广泛的推广和应用.然而,空气源热泵在低温高湿环境下的结霜问题严重制约了其高效稳定运行.首先从结霜机理出发,将表面冷凝结霜的初期划分为液滴冷凝、液滴开始冻结、霜层传播和霜层积聚四个阶段.其次,对近年来空气源热泵的常见抑霜方法进行了总结归纳,重点介绍了调整蒸发器入口空气参数、优化换热器结构设计、换热器表面改性和外加电磁场等抑霜方法的研究进展.此外,介绍了现有空气源热泵常见的除霜方法及研究现状,并为实现空气源热泵在低温高湿条件下的高效运行,提出了进一步研究的方向和
The present study is dedicated to light-strange A with strangeness S =-1 and isospin I =0,∑ with S =-1 and I =1,and[I]baryon with S =-2 and I =1/2.In this study,the hypercentral constituent quark model with lin-ear confining potential has been employed al
In this article,we illustrate how to calculate the hadronic coupling constants of the pentaquark states with QCD sum rules based on rigorous quark-hadron quality.We then study the hadronic coupling constants of the low-est diquark-diquark-antiquark type h
Inspired by the newly observed X0(2900) and X1 (2900) states at LHCb,the K*(D)* and K(D)1 interactions are studied in the quasipotential Bethe-Salpeter equation approach combined with the one-boson-exchange model.The bound and virtual states from the inte
First-principle calculations within the density functional theory framework are used to study the probab-ility of electron capture for the 7Be nucleus.For this purpose,electron density at the 7Be nucleus is computed in A1,Au,Pd,Pt,and Pb environments.Our
The formation of large size clusters,and/or their relative motion as a possible excitation mode,are sug-gested to be closely related to the origin of deformation in specific cases,namely the case of two doubly-magic clusters or two clusters with nearby ch
We studied the pair production of charged scalar particles of a five-dimensional near extremal Reissner-Nordstr(o)m-Anti de Sitter (RN-AdS5) black hole.The pair production rate and the absorption cross section ratio in full spacetime are obtained and are