Open Access
ND 2007
Article Number 347
Number of page(s) 4
Section Astrophysics applications
Published online 17 June 2008
International Conference on Nuclear Data for Science and Technology 2007
DOI: 10.1051/ndata:07493

Improved lead and bismuth (n,γ) cross sections and their astrophysical impact

C. Domingo-Pardo1, 2, U. Abbondanno3, G. Aerts4, H. Álvarez5, F. Álvarez-Velarde6, S. Andriamonje4, J. Andrzejewski7, P. Assimakopoulos8, L. Audouin9, G. Badurek10, P. Baumann11, F. Becvár12, E. Berthoumieux4, F. Calviño13, M. Calviani14, 15, D. Cano-Ott6, R. Capote16, 17, C. Carrapiço4, 18, P. Cennini19, V. Chepel20, E. Chiaveri19, N. Colonna21, G. Cortes22, A. Couture23, J. Cox23, M. Dahlfors19, S. David9, I. Dillmann1, W. Dridi4, I. Duran5, C. Eleftheriadis24, M. Embid-Segura6, L. Ferrant9, A. Ferrari19, R. Ferreira-Marques20, K. Fujii3, W. Furman25, I. Goncalves20, E. González-Romero6, F. Gramegna14, C. Guerrero6, F. Gunsing4, B. Haas26, R. Haight27, M. Heil1, A. Herrera-Martinez19, M. Igashira28, E. Jericha10, F. Käppeler1, Y. Kadi19, D. Karadimos8, D. Karamanis8, M. Kerveno11, P. Koehler29, E. Kossionides30, M. Krticka12, C. Lampoudis4, 24, H. Leeb10, A. Lindote20, I. Lopes20, M. Lozano17, S. Lukic11, J. Marganiec7, S. Marrone21, T. Martínez6, C. Massimi31, P. Mastinu14, A. Mengoni16, 19, P.M. Milazzo3, C. Moreau3, M. Mosconi1, F. Neves20, H. Oberhummer10, S. O'Brien23, J. Pancin4, C. Papachristodoulou8, C. Papadopoulos32, C. Paradela5, N. Patronis8, A. Pavlik33, P. Pavlopoulos34, L. Perrot4, M.T. Pigni10, R. Plag1, A. Plompen35, A. Plukis4, A. Poch22, J. Praena14, C. Pretel22, J. Quesada17, T. Rauscher36, R. Reifarth27, C. Rubbia37, G. Rudolf11, P. Rullhusen35, J. Salgado18, C. Santos18, L. Sarchiapone19, I. Savvidis24, C. Stephan9, G. Tagliente21, J.L. Tain0, L. Tassan-Got9, L. Tavora18, R. Terlizzi21, G. Vannini31, P. Vaz18, A. Ventura38, D. Villamarin6, M.C. Vincente6, V. Vlachoudis19, R. Vlastou32, F. Voss1, S. Walter1, M. Wiescher23 and K. Wisshak1

1  Forschungszentrum Karlsruhe GmbH (FZK), Institut für Kernphysik, Germany
2  Instituto de Física Corpuscular, CSIC-Universidad de Valencia, Spain
3  Istituto Nazionale di Fisica Nucleare, Trieste, Italy
4  CEA/Saclay-DSM/DAPNIA, Gif-sur-Yvette, France
5  Universidade de Santiago de Compostela, Spain
6  Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, Madrid, Spain
7  University of Lodz, Lodz, Poland
8  University of Ioannina, Greece
9  Centre National de la Recherche Scientifique/IN2P3-IPN, Orsay, France
10  Atominstitut der Österreichischen Universitäten, Technische Universität Wien, Austria
11  Centre National de la Recherche Scientifique/IN2P3-IReS, Strasbourg, France
12  Charles University, Prague, Czech Republic
13  Universidad Politecnica de Madrid, Spain
14  Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Italy
15  Dipartimento di Fisica, Università di Padova, Italy
16  International Atomic Energy Agency (IAEA), Nuclear Data Section, Vienna, Austria
17  Universidad de Sevilla, Spain
18  Instituto Tecnológico e Nuclear (ITN), Lisbon, Portugal
19  CERN, Geneva, Switzerland
20  LIP-Coimbra & Departamento de Fisica da Universidade de Coimbra, Portugal
21  Istituto Nazionale di Fisica Nucleare, Bari, Italy
22  Universitat Politecnica de Catalunya, Barcelona, Spain
23  University of Notre Dame, Notre Dame, USA
24  Aristotle University of Thessaloniki, Greece
25  Joint Institute for Nuclear Research, Frank Laboratory of Neutron Physics, Dubna, Russia
26  Centre National de la Recherche Scientifique/IN2P3 - CENBG, Bordeaux, France
27  Los Alamos National Laboratory, New Mexico, USA
28  Tokyo Institute of Technology, Tokyo, Japan
29  Oak Ridge National Laboratory, Physics Division, Oak Ridge, USA
30  NCSR, Athens, Greece
31  Dipartimento di Fisica, Università di Bologna, and Sezione INFN di Bologna, Italy
32  National Technical University of Athens, Greece
33  Institut für Isotopenforschung und Kernphysik, Universität Wien, Austria
34  Pôle Universitaire Léonard de Vinci, Paris-La Défense, France
35  CEC-JRC-IRMM, Geel, Belgium
36  Department of Physics, University of Basel, Switzerland
37  Università degli Studi Pavia, Pavia, Italy
38  ENEA, Bologna, Italy

Published online: 21 May 2008

A series of (n,γ) neutron capture measurements on the lead isotopes and bismuth have been carried out at the CERN n_TOF installation in the neutron energy range from 1 eV up to 1 MeV. At n_TOF, contaminations due to scattered neutrons were reduced down to a negligible level by using improved γ-ray detectors with very low neutron sensitivity. The background level has been determined precisely from a complementary measurement. Other experimental effects related to the electronic threshold in the detectors and the angular distribution of the prompt γ-rays were investigated via Monte Carlo simulations and could be taken in account in the analysis of the capture data. With this set of measurements the energy differential (n,γ) cross sections of 204,206,207Pb and 209Bi have been determined with good accuracy. The information obtained in this work becomes of interest for constraining r-process calculations and in particular for the Th/U cosmochronometer.

© CEA 2008