Summary
In this paper, we present deep underground neutron flux measurements performed by large BF3 counters in the Gran Sasso underground laboratory. A neutron flux of (1.08±0.02)·10−6 cm−2 s−1 for the thermal component and (1.98±0.05)·10−6 cm−2 s−1 for the epithermal one [here (50·10−3÷1·103) eV] is found. The fast component with an energy over 2.5 MeV turns out to be equal to (0.23±0.07)·10−6 cm−2 s−1 and its energy distribution appears to be compatible with a fission spectrum.
Riassunto
In questo lavoro, presentiamo la misura del flusso di neutroni nel laboratorio sotterraneo del Gran Sasso, realizzata mediante l'impiego di grandi contatori BF3. Il flusso misurato è di (1.08±0.02)·10−6 cm−2 s−1 per la componente termica e di (1.98±0.05)·10−6 cm−2 s−1 per l'epitermica (qui (50·10−3÷1·103) eV). Il flusso della componente veloce con una energia superiore a 2.5 MeV risulta uguale a (0.23±0.07)·10−6 cm−2 s−1. La sua distribuzione energetica è compatibile con uno spettro di fissione.
Резюме
В этой работе приводятся результаты измерений потока нейтронов глубоко под Землей, проведенных с помощью бслыших BF3 детокторов в подземной лаборатории Гран Cacco. Измерен поток нейтронов (1.08±0.002)·10−6 cm−2·c−1 для тепловой компоненты и (1.98±0.05)·10−6 cm−2·c−1 для надтепловой компоненты (здесь (50·10−3÷1·103) эВ). Поток для компоненты с энергиями 2.5 МэВ оказывается равным (0.23±0.07)·10−6 cm−2·c−1. Энергетическое распределение оказывается сопоставимым со спектром деления.
Similar content being viewed by others
Literatur
A. Zichichi:The Gran Sasso project, Proceedings of Physics and Astrophysics with a Multikiloton Modular Underground Detector, Rome (October 29–31, 1981), p. 141;The Gran Sasso Laboratory, invited paper toICOMAN 83 Meeting (Frascati, 1983);The Gran Sasso Project, INFN/AE-82/1 (1982).
T. Kirsteen et al.: Gallium solar neutrino experiment, Proposal for the Gran Sasso Laboratory (1985).
I. L. Fowler:Rev. Sci. Instr.,34, 731 (1963).
E. Bellotti, M. Buraschi, E. Fiorini andC. Liguori:New measurement of rock contaminations and neutron activity in the Gran Sasso tunnel, INFN/TC-85/19;E. Fiorini, C. Liguori andA. Rindi:Preliminary measurements of the gamma ray and neutron background in the Gran Sasso tunnel, LNF-85/7(R).
A. Rindi, f. Celani, F. Cardone, S. Miozzi, M. Lindozzi andA. Pecchi:New measurements of neutron flux in the Gran Sasso tunnel, LNF-86/16(R).
R. Aleksan, J. Bouchez, M. Cribier, E. Kajfasz, B. Pichard, F. Pierre, J. Poinsignon, M. Spiro andJ. F. Thomas:Measurement of fast neutrons in the Gran Sasso Laboratory using a 6Lidoped liquid scintillator, DPhPE 88-09.
MCNP.A general purpose Monte Carlo code for neutron and photon transport (ver. 3A), LA-7336-M, Los Alamos National Laboratory (1981).
Author information
Authors and Affiliations
Additional information
To speed up publication, the authors of this paper have agreed to not receive the proofs for correction.
Перевебено ребакцией.
Rights and permissions
About this article
Cite this article
Belli, P., Bernabei, R., d'Angelo, S. et al. Deep underground neutron flux measurement with large BF3 counters. Nuov Cim A 101, 959–966 (1989). https://doi.org/10.1007/BF02800162
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF02800162