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Title: Novel Techniques for Constraining Neutron-Capture Rates Relevant to Heavy-element Nucleosynthesis

Authors:
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Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1343842
Report Number(s):
LLNL-PROC-722079
DOE Contract Number:
AC52-07NA27344
Resource Type:
Conference
Resource Relation:
Conference: Presented at: International Nuclear Physics Conference 2016, Adelaide, Australia, Sep 11 - Sep 16, 2016
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Larsen, A C, Spyrou, A, Liddick, S N, Guttormsen, M, Ingeberg, V W, Siem, S, Wiedeking, M, Crider, B P, Naqvi, F, Perdikakis, G, Mumpower, M R, Surman, R, Tveten, G M, Bleuel, D L, Couture, A, Campo, L C, Dombos, A C, Gorgen, A, Lewis, R, Mosby, S M, Nikas, S, Prokop, C J, Quinn, S J, Renstrom, T, and Rubio, B. Novel Techniques for Constraining Neutron-Capture Rates Relevant to Heavy-element Nucleosynthesis. United States: N. p., 2017. Web.
Larsen, A C, Spyrou, A, Liddick, S N, Guttormsen, M, Ingeberg, V W, Siem, S, Wiedeking, M, Crider, B P, Naqvi, F, Perdikakis, G, Mumpower, M R, Surman, R, Tveten, G M, Bleuel, D L, Couture, A, Campo, L C, Dombos, A C, Gorgen, A, Lewis, R, Mosby, S M, Nikas, S, Prokop, C J, Quinn, S J, Renstrom, T, & Rubio, B. Novel Techniques for Constraining Neutron-Capture Rates Relevant to Heavy-element Nucleosynthesis. United States.
Larsen, A C, Spyrou, A, Liddick, S N, Guttormsen, M, Ingeberg, V W, Siem, S, Wiedeking, M, Crider, B P, Naqvi, F, Perdikakis, G, Mumpower, M R, Surman, R, Tveten, G M, Bleuel, D L, Couture, A, Campo, L C, Dombos, A C, Gorgen, A, Lewis, R, Mosby, S M, Nikas, S, Prokop, C J, Quinn, S J, Renstrom, T, and Rubio, B. Thu . "Novel Techniques for Constraining Neutron-Capture Rates Relevant to Heavy-element Nucleosynthesis". United States. doi:. https://www.osti.gov/servlets/purl/1343842.
@article{osti_1343842,
title = {Novel Techniques for Constraining Neutron-Capture Rates Relevant to Heavy-element Nucleosynthesis},
author = {Larsen, A C and Spyrou, A and Liddick, S N and Guttormsen, M and Ingeberg, V W and Siem, S and Wiedeking, M and Crider, B P and Naqvi, F and Perdikakis, G and Mumpower, M R and Surman, R and Tveten, G M and Bleuel, D L and Couture, A and Campo, L C and Dombos, A C and Gorgen, A and Lewis, R and Mosby, S M and Nikas, S and Prokop, C J and Quinn, S J and Renstrom, T and Rubio, B},
abstractNote = {},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 26 00:00:00 EST 2017},
month = {Thu Jan 26 00:00:00 EST 2017}
}

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  • The neutron capture cross sections of /sup 112/Sn, /sup 130/Ba, /sup 146/Nd, /sup 148/Nd, /sup 186/W, /sup 190/Os, and /sup 192/Os at 24 keV neutron energy were measured with respect to /sup 197/Au by activation in a 24 keV neutron beam at the Brookhaven High Flux Beam Reactor. The reliability of this technique was verified by remeasuring the cross section of /sup 186/W and comparing it to previous measurements. This continuing series of measurements will provide a more reliable data base for nucleosynthesis calculations. 12 references.
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  • Neutron-capture reactions play an important role in heavy element nucleosynthesis, since they are the driving force for the two processes that create the vast majority of the heavy elements. When a neutron capture occurs on a short-lived nucleus, it is extremely challenging to study the reaction directly and therefore the use of indirect techniques is essential. The present work reports on such an indirect measurement that provides strong constraints on the 68Ni(n,g) 69Ni reaction rate.The commonly used reaction libraries JINA-REACLIB and BRUSLIB are in relatively good agreement with the experimental rate. The impact of the new rate on weak r-processmore » calculations is discussed.« less