Experimental setup and procedure for the measurement of the ⁷Be(n,α)α reaction at n_TOF

详细信息    查看全文

• 作者：L. Cosentino^a ; A. Musumarra^a ; ^b ; M. Barbagallo^c ; A. Pappalardo^a ; N. Colonna^c ; L. Damone^c ; M. Piscopo^a ; P. Finocchiaro^a ; ^{FINOCCHIARO@LNS.INFN.IT" class="auth_mail" title="E-mail the corresponding author} ; E. Maugeri^d ; S. Heinitz^d ; D. Schumann^d ; R. Dressler^d ; N. Kivel^d ; O. Aberle^e ; J. Andrzejewski^f ; L. Audouin^g ; M. Ayranov^h ; M. Bacakⁱ ; S. Barros^j ; J. Balibrea-Correa^k ; V. Bé ; cares^k ; F. Bečvá ; ř^l ; C. Beinrucker^m ; E. Berthoumieuxⁿ ; J. Billowes^o ; D. Bosnar^p ; M. Brugger^e ; M. Caama&ntilde ; o^q ; M. Calviani^e ; F. Calvi&ntilde ; o^r ; D. Cano-Ott^k ; R. Cardella^a ; ^e ; A. Casanovas^r ; D.M. Castelluccio^s ; ^t ; F. Cerutti^e ; Y.H. Chen^g ; E. Chiaveri^e ; G. Corté ; s^r ; M.A. Corté ; s-Giraldo^u ; M. Diakakiⁿ ; C. Domingo-Pardo^v ; E. Dupontⁿ ; I. Duran^q ; B. Fernandez-Dominguez^q ; A. Ferrari^e ; P. Ferreira^j ; W. Furman^w ; S. Ganesan^x ; A. Garcí ; a-Rios^k ; A. Gawlik^f
• 关键词：Cosmological lithium problem ; Big bang nucleosynthesis ; 7Be(n ; α)α reaction ; n_TOF spallation neutron source
• 刊名：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
• 出版年：2016
• 出版时间：11 September 2016
• 年：2016
• 卷：830
• 期：Complete
• 页码：197-205
• 全文大小：2488 K

文摘

The newly built second experimental area EAR2 of the n_TOF spallation neutron source at CERN allows to perform (n, charged particles) experiments on short-lived highly radioactive targets. This paper describes a detection apparatus and the experimental procedure for the determination of the cross-section of the ⁷Be(n,α)α reaction, which represents one of the focal points toward the solution of the cosmological Lithium abundance problem, and whose only measurement, at thermal energy, dates back to 1963.

The apparently unsurmountable experimental difficulties stemming from the huge ⁷Be γ-activity, along with the lack of a suitable neutron beam facility, had so far prevented further measurements. The detection system is subject to considerable radiation damage, but is capable of disentangling the rare reaction signals from the very high background. This newly developed setup could likely be useful also to study other challenging reactions requiring the detectors to be installed directly in the neutron beam.