Investigation of ortho <-> para hydrogen conversion by collisions with neutrons

doi:10.1080/00223131.2017.1412363

IHEP OpenIR > 东莞研究部

	Investigation of ortho <-> para hydrogen conversion by collisions with neutrons
	Mei LW(梅龙伟); Shen F(沈飞); Wang SL(王松林); Hu ZL(胡志良); 周斌(东); Liang TJ(梁天骄); Mei, LW; Liu, C; Shen, F; Wang, SL; Hu, ZL; Zhou, B; Liang, TJ
	2018
发表期刊	JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY (IF:0.965[JCR-2016],1.276[5-Year])
ISSN	0022-3131
EISSN	1881-1248
卷号	55 期号:5 页码:478-483
文章类型	Article
摘要	Liquid hydrogen (LH) is constituted by para hydrogen (pH) and ortho hydrogen (oH) molecules. We analyzed the neutron scattering cross sections for pHoH, pHpH, oHpH, and oHoH reactions in LH. Results show that incident neutron energy lower than 14.7meV is not sufficient to achieve pHoH conversion. As energy increases, the cross section of pHoH reaction increases sharply. If incident neutron energy is larger than 30 meV, branching fraction of pH molecules being converted into oH molecules upon inelastic scattering with the neutrons approaches 100%. As for the opposite process, branching fraction of oHpH conversion is 10%-20% when incident neutron energy is lower than 30 meV. This conversion fraction oscillates with increasing incident neutron energy, eventually stabilizing at 30%. Based on the cross sections of the four reaction channels, we calculated the corresponding conversion rates based on a reactor cold neutron source model. There is 0.12% pH molecules of LH moderator would be converted to oH for one month operation . If neutron flux increased by 2 orders of magnitude, more than 10% pH would be transformed into oH, which means relative conversion rate of pHoH induced by neutron inelastic scattering is not negligible.
关键词	MCNP neutron source liquid hydrogen para-ortho hydrogen conversion thermal neutron scattering cryogenic moderator cross section
DOI	10.1080/00223131.2017.1412363
关键词[WOS]	HOMONUCLEAR DIATOMIC LIQUIDS ; SCATTERING ; ROTATION
收录类别	SCI ; ADS ; EI
语种	英语
WOS研究方向	Nuclear Science & Technology
WOS类目	Nuclear Science & Technology
WOS记录号	WOS:000428678300002
EI入藏号	20180504689949
ADS Bibcode	2018JNST...55..478M
ADS URL	https://ui.adsabs.harvard.edu/abs/2018JNST...55..478M
ADS引文	https://ui.adsabs.harvard.edu/abs/2018JNST...55..478M/citations
引用统计	正在获取... 被引频次：0 [ADS]
文献类型	期刊论文
条目标识符	https://ir.ihep.ac.cn/handle/311005/285789
专题	东莞研究部实验物理中心中国科学院高能物理研究所_中国散裂中子源
通讯作者	Mei LW(梅龙伟)
作者单位	中国科学院高能物理研究所
第一作者单位	中国科学院高能物理研究所
通讯作者单位	中国科学院高能物理研究所
推荐引用方式 GB/T 7714	Mei LW,Shen F,Wang SL,et al. Investigation of ortho <-> para hydrogen conversion by collisions with neutrons[J]. JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY,2018,55(5):478-483.
APA	梅龙伟.,沈飞.,王松林.,胡志良.,周斌.,...&Liang, TJ.(2018).Investigation of ortho <-> para hydrogen conversion by collisions with neutrons.JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY,55(5),478-483.
MLA	梅龙伟,et al."Investigation of ortho <-> para hydrogen conversion by collisions with neutrons".JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY 55.5(2018):478-483.