F. Delaunay, N. Achouri, A. Algora, M. Assi'e, J. Balibrea, K. Banerjee, C. Bhattacharya, M. Borge, D. Cano-Ott, B. Fern'andez-Dom'inguez, L. Fraile, J. Gibelin, M. Lund, M. Madurga, F. Marqu'es, I. Marroquı́n, T. Mart'inez, E. Mendoza, N. Orr, M. Pârlog, X. Pereira-L'opez, V. Pestel, K. Riisager, C. Santos, M. Sénoville, O. Tengblad, V. Vedia
{"title":"$^{11}$Li $\\beta$衰变中多中子发射的研究","authors":"F. Delaunay, N. Achouri, A. Algora, M. Assi'e, J. Balibrea, K. Banerjee, C. Bhattacharya, M. Borge, D. Cano-Ott, B. Fern'andez-Dom'inguez, L. Fraile, J. Gibelin, M. Lund, M. Madurga, F. Marqu'es, I. Marroquı́n, T. Mart'inez, E. Mendoza, N. Orr, M. Pârlog, X. Pereira-L'opez, V. Pestel, K. Riisager, C. Santos, M. Sénoville, O. Tengblad, V. Vedia","doi":"10.1393/NCC/I2019-19098-5","DOIUrl":null,"url":null,"abstract":"The kinematics of two-neutron emission following the $\\beta$-decay of $^{11}$Li was investigated for the first time by detecting the two neutrons in coincidence and by measuring their angle and energy. An array of liquid-scintillator neutron detectors was used to reject cosmic-ray and $\\gamma$-ray backgrounds by pulse-shape discrimination. Cross-talk events in which two detectors are fired by a single neutron were rejected using a filter tested on the $\\beta$-1n emitter $^9$Li. A large cross-talk rejection rate is obtained ($> 95 \\%$) over most of the energy range of interest. Application to $^{11}$Li data leads to a significant number of events interpreted as $\\beta$-2n decay. A discrete neutron line at $\\approx$ 2 MeV indicates sequential two-neutron emission, possibly from the unbound state at 10.6 MeV excitation energy in $^{11}$Be.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2018-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Study of multi-neutron emission in the $\\\\beta$-decay of $^{11}$Li\",\"authors\":\"F. Delaunay, N. Achouri, A. Algora, M. Assi'e, J. Balibrea, K. Banerjee, C. Bhattacharya, M. Borge, D. Cano-Ott, B. Fern'andez-Dom'inguez, L. Fraile, J. Gibelin, M. Lund, M. Madurga, F. Marqu'es, I. Marroquı́n, T. Mart'inez, E. Mendoza, N. Orr, M. Pârlog, X. Pereira-L'opez, V. Pestel, K. Riisager, C. Santos, M. Sénoville, O. Tengblad, V. Vedia\",\"doi\":\"10.1393/NCC/I2019-19098-5\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The kinematics of two-neutron emission following the $\\\\beta$-decay of $^{11}$Li was investigated for the first time by detecting the two neutrons in coincidence and by measuring their angle and energy. An array of liquid-scintillator neutron detectors was used to reject cosmic-ray and $\\\\gamma$-ray backgrounds by pulse-shape discrimination. Cross-talk events in which two detectors are fired by a single neutron were rejected using a filter tested on the $\\\\beta$-1n emitter $^9$Li. A large cross-talk rejection rate is obtained ($> 95 \\\\%$) over most of the energy range of interest. Application to $^{11}$Li data leads to a significant number of events interpreted as $\\\\beta$-2n decay. A discrete neutron line at $\\\\approx$ 2 MeV indicates sequential two-neutron emission, possibly from the unbound state at 10.6 MeV excitation energy in $^{11}$Be.\",\"PeriodicalId\":8464,\"journal\":{\"name\":\"arXiv: Nuclear Experiment\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2018-09-02\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv: Nuclear Experiment\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1393/NCC/I2019-19098-5\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv: Nuclear Experiment","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1393/NCC/I2019-19098-5","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Study of multi-neutron emission in the $\beta$-decay of $^{11}$Li
The kinematics of two-neutron emission following the $\beta$-decay of $^{11}$Li was investigated for the first time by detecting the two neutrons in coincidence and by measuring their angle and energy. An array of liquid-scintillator neutron detectors was used to reject cosmic-ray and $\gamma$-ray backgrounds by pulse-shape discrimination. Cross-talk events in which two detectors are fired by a single neutron were rejected using a filter tested on the $\beta$-1n emitter $^9$Li. A large cross-talk rejection rate is obtained ($> 95 \%$) over most of the energy range of interest. Application to $^{11}$Li data leads to a significant number of events interpreted as $\beta$-2n decay. A discrete neutron line at $\approx$ 2 MeV indicates sequential two-neutron emission, possibly from the unbound state at 10.6 MeV excitation energy in $^{11}$Be.