β-decay and β-delayed Neutron Emission Measurements at GSI-FRS
Beyond N =126, for r-process Nucleosynthesis
R. Caballero-Folch,
1, *
C. Domingo-Pardo,
2
G. Cort` es,
1
J.L. Ta´ ın,
2
J. Agramunt,
2
A. Algora,
2, 3
F. Ameil,
4
Y. Ayyad,
5
J. Benlliure,
5
M. Bowry,
6
F. Calvi˜ no,
1
D. Cano-Ott,
7
T. Davinson,
8
I. Dillmann,
4, 9
A. Estrade,
4, 10
A. Evdokimov,
4, 9
T. Faestermann,
11
F. Farinon,
4
D. Galaviz,
12
A. Garc´ ıa-R´ ıos,
7
H. Geissel,
4, 9
W. Gelletly,
6
R. Gernh¨ auser,
11
M.B. G´ omez-Hornillos,
1
C. Guerrero,
13
M. Heil,
4
C. Hinke,
11
R. Kn¨ obel,
4
I. Kojouharov,
4
J. Kurcewicz,
4
N. Kurz,
4
Y. Litvinov,
4
L. Maier,
11
J. Marganiec,
14
M. Marta,
4, 9
T. Mart´ ınez,
7
F. Montes,
15, 16
I. Mukha,
4
D.R. Napoli,
17
C. Nociforo,
4
C. Paradela,
5
S. Pietri,
4
Zs. Podoly´ ak,
6
A. Prochazka,
4
S. Rice,
6
A. Riego,
1
B. Rubio,
2
H. Schaffner,
4
C. Scheidenberger,
4, 9
K. Smith,
18, 19, 15, 16
E. Sokol,
20
K. Steiger,
11
B. Sun,
4
M. Takechi,
4
D. Testov,
20, 21
H. Weick,
4
E. Wilson,
6
J.S. Winfield,
4
R. Wood,
6
P.J. Woods,
8
and A. Yeremin
20
1
Deptartament de F´ ısica i Enginyeria Nuclear, Universitat Polit` ecnica de Catalunya, E-08028 Barcelona, Spain
2
Institut de F´ ısica Corpuscular, CSIC-Universitat de Val` encia, E-46071 Val` encia, Spain
3
Institute of Nuclear Research of Hungarian Academy of Sciences, Debrecen, Hungary
4
GSI Helmholtzzentrum f¨ ur Schwerionenforschung, D-64291, Darmstadt, Germany
5
Universidade de Santiago de Compostela, E-15782, Santiago de Compostela, Spain
6
Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
7
Centro de Investigaciones energ´ eticas Medioambientales y Tecnol´ogicas, Madrid, Spain
8
School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ United Kingdom
9
II. Physikalisches Institut, Justus-Liebig Universit¨ at Giessen, D-35392 Giessen, Germany
10
St. Mary’s University, Halifax, Nova Scotia, Canada B3H 3C3
11
Physik Department E12, Technische Universit¨at M¨ unchen, DE-85748 Garching, Germany
12
Centro de F´ ısica Nuclear da Universidade de Lisboa, 169-003 Lisboa, Portugal
13
CERN, Geneva, Switzerland
14
EMMI, GSI Helmholtzzentrum f¨ ur Schwerionenforschung, D-64291, Darmstadt, Germany
15
National Superconducting Cyclotron Laboratory,
Michigan State University, East Lansing, Michigan 48824, USA
16
Joint Institute for Nuclear Astrophysics (JINA),
Michigan State University, East Lansing, Michigan 48824, USA
17
Instituto Nazionale di Fisica Nucleare, Laboratori Nazionale di Legnaro, Legnaro, Italy
18
Department of Physics, University of Notre Dame, South Bend, Indiana 46556 USA
19
Joint Institute for Nuclear Astrophysics (JINA),
University of Notre Dame, South Bend, Indiana 46556 USA
20
Flerov Laboratory, Joint Institute for Nuclear Research, Dubna, Russia
21
IPN Orsay, France
New measurements of very exotic nuclei in the neutron-rich region beyond N=126 have been
performed at the GSI facility with the fragment separator (FRS). The aim of the experiment is
to determine half-lives and β-delayed neutron emission branching ratios of isotopes of Hg, Tl and
Pb in this region. This contribution summarizes final counting statistics for identification and for
implantation, as well as the present status of the data analysis of the half-lives. In summary, isotopes
of Pt, Au, Hg, Tl, Pb, Bi, Po, At, Rn and Fr were clearly identified and several of them (
208-211
Hg,
211-215
Tl,
214-218
Pb) were implanted with enough statistics to determine their half-lives. About
half of them are expected to be neutron emitters, in such cases it will become possible to obtain the
neutron emission probabilities, Pn.
*
Corresponding author: roger.caballero@upc.edu
I. INTRODUCTION
The r-process is one of the mechanisms proposed to
explain the origin of the elements heavier than iron and
involves an enormous amount of very neutron-rich nuclei,
Available online at www.sciencedirect.com
Nuclear Data Sheets 120 (2014) 81–83
0090-3752/© 2014 Elsevier Inc. All rights reserved.
www.elsevier.com/locate/nds
http://dx.doi.org/10.1016/j.nds.2014.07.012