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Title: Precision measurement of the decay rate of {sup 7}Be in host materials

Abstract

A controlled and precise determination of the cross sections of the fusion reactions {sup 7}Be(p,{gamma}){sup 8}B and {sup 3}He({sup 4}He,{gamma}){sup 7}Be, which play an important role in determining the solar neutrino flux, necessitates the knowledge of a precise value of the electron-capture half-life of {sup 7}Be. This half-life may depend on the material hosting the {sup 7}Be atoms via small modifications of the electron density around the {sup 7}Be nucleus. In this brief communication we report on the measurement of {sup 7}Be implanted in four materials: copper, aluminum, sapphire, and PVC. The four results are consistent with a null host dependence within two standard deviations and their weighted average of 53.236(39) d agrees very well with the adopted value in the literature, 53.22(6) d. The present results may exhibit a slight (0.22%) increase of the half-life at room temperature for metals compared to insulators that requires further studies.

Authors:
; ;  [1]; ; ; ; ;  [2];  [3];  [4]; ; ;  [3];  [3];  [4];  [5];  [6]; ;  [7]
  1. Radiation Safety Division, Soreq Nuclear Research Centre, Yavne (Israel)
  2. Department of Particle Physics, Weizmann Institute of Science, Rehovot (Israel)
  3. ISOLDE, CERN, Geneva (Switzerland)
  4. (France)
  5. Physics Department, University of Manchester, Manchester (United Kingdom)
  6. Laboratory of Radiochemistry, Paul Scherrer Institute, Villigen (Switzerland)
  7. Target Facilities and Active Technique Section, Accelerator Division, Paul Scherrer Institute, Villigen (Switzerland)
Publication Date:
OSTI Identifier:
20990927
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevC.75.012801; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ALPHA PARTICLES; ALUMINIUM; BERYLLIUM 7; BORON 8; COPPER; ELECTRON CAPTURE; HALF-LIFE; HEAVY ION FUSION REACTIONS; HELIUM 3; HELIUM 4; PROTON REACTIONS; PROTON-NUCLEON INTERACTIONS; PVC; SAPPHIRE; SOLAR NEUTRINOS; TEMPERATURE RANGE 0273-0400 K; TRITONS

Citation Formats

Nir-El, Y., Haquin, G., Yungreiss, Z., Hass, M., Goldring, G., Chamoli, S. K., Singh, B. S. Nara, Lakshmi, S., Koester, U., Institut Laue Langevin, Grenoble, Champault, N., Dorsival, A., Fedoseyev, V. N., Georgiev, G., CSNSM, CNRS/IN2P3, Universite Paris-Sud, ORSAY-Campus, Marsh, B. A., Schumann, D., Heidenreich, G., and Teichmann, S. Precision measurement of the decay rate of {sup 7}Be in host materials. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.012801.
Nir-El, Y., Haquin, G., Yungreiss, Z., Hass, M., Goldring, G., Chamoli, S. K., Singh, B. S. Nara, Lakshmi, S., Koester, U., Institut Laue Langevin, Grenoble, Champault, N., Dorsival, A., Fedoseyev, V. N., Georgiev, G., CSNSM, CNRS/IN2P3, Universite Paris-Sud, ORSAY-Campus, Marsh, B. A., Schumann, D., Heidenreich, G., & Teichmann, S. Precision measurement of the decay rate of {sup 7}Be in host materials. United States. doi:10.1103/PHYSREVC.75.012801.
Nir-El, Y., Haquin, G., Yungreiss, Z., Hass, M., Goldring, G., Chamoli, S. K., Singh, B. S. Nara, Lakshmi, S., Koester, U., Institut Laue Langevin, Grenoble, Champault, N., Dorsival, A., Fedoseyev, V. N., Georgiev, G., CSNSM, CNRS/IN2P3, Universite Paris-Sud, ORSAY-Campus, Marsh, B. A., Schumann, D., Heidenreich, G., and Teichmann, S. Mon . "Precision measurement of the decay rate of {sup 7}Be in host materials". United States. doi:10.1103/PHYSREVC.75.012801.
@article{osti_20990927,
title = {Precision measurement of the decay rate of {sup 7}Be in host materials},
author = {Nir-El, Y. and Haquin, G. and Yungreiss, Z. and Hass, M. and Goldring, G. and Chamoli, S. K. and Singh, B. S. Nara and Lakshmi, S. and Koester, U. and Institut Laue Langevin, Grenoble and Champault, N. and Dorsival, A. and Fedoseyev, V. N. and Georgiev, G. and CSNSM, CNRS/IN2P3, Universite Paris-Sud, ORSAY-Campus and Marsh, B. A. and Schumann, D. and Heidenreich, G. and Teichmann, S.},
abstractNote = {A controlled and precise determination of the cross sections of the fusion reactions {sup 7}Be(p,{gamma}){sup 8}B and {sup 3}He({sup 4}He,{gamma}){sup 7}Be, which play an important role in determining the solar neutrino flux, necessitates the knowledge of a precise value of the electron-capture half-life of {sup 7}Be. This half-life may depend on the material hosting the {sup 7}Be atoms via small modifications of the electron density around the {sup 7}Be nucleus. In this brief communication we report on the measurement of {sup 7}Be implanted in four materials: copper, aluminum, sapphire, and PVC. The four results are consistent with a null host dependence within two standard deviations and their weighted average of 53.236(39) d agrees very well with the adopted value in the literature, 53.22(6) d. The present results may exhibit a slight (0.22%) increase of the half-life at room temperature for metals compared to insulators that requires further studies.},
doi = {10.1103/PHYSREVC.75.012801},
journal = {Physical Review. C, Nuclear Physics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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