Total Cross Sections for Ultracold Neutrons Scattered from Gases
Total Cross Sections for Ultracold Neutrons Scattered from Gases
复制标题
气体散射的超冷中子的总横截面
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
B. Zeck
中科院分区：
文献类型：
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作者：
S. Seestrom;E. Adamek;D. Barlow;M. Blatnik;L. Broussard;N. Callahan;S. Clayton;C. Cude;S. Currie;E. Dees;W. Fox;M. Hoffbauer;K. Hickerson;A. Holley;Chen;M. Makela;J. Medina;D. Morley;C. Morris;R. Pattie;J. Ramsey;A. Roberts;D. Salvat;A. Saunders;E. Sharapov;S. Sjue;B. Slaughter;P. Walstrom;Zhehui Wang;J. Wexler;T. Womack;A. Young;J. Vanderwerp;B. Zeck
我们对一系列气体的超冷中子（ucn）的上散射进行了后续测量，测量了以下气体的总横截面：氢、乙烷、甲烷、异丁烯、正丁烷、乙烯、水蒸气、丙烷、新戊烷、异丙醇和^3He。这些截面的值对于估计由于残余气体而捕获的中子的损失率很重要，并且与使用ucn测量中子寿命有关。利用蒙特卡罗传输码分析了UCN速度和路径长度分布的影响。结果与我们以前的测量结果和^3He的已知吸收截面进行了比较，并按我们的UCN能量进行了缩放。我们发现烃类气体的总横截面可以用分子中氢原子数的线性函数来合理地描述。
We have followed up on our previous measurements of upscattering of ultracold neutrons (UCNs) from a series of gases by making measurements of total cross sections on the following gases hydrogen, ethane, methane, isobutene, n-butane, ethylene, water vapor, propane, neopentane, isopropyl alcohol, and ^3He. The values of these cross sections are important for estimating the loss rate of trapped neutrons due to residual gas and are relevant to neutron lifetime measurements using UCNs. The effects of the UCN velocity and path-length distributions were accounted for in the analysis using a Monte Carlo transport code. Results are compared to our previous measurements and with the known absorption cross section for ^3He scaled to our UCN energy. We find that the total cross sections for the hydrocarbon gases are reasonably described by a function linear in the number of hydrogen atoms in the molecule.