|
Records |
Links |
|
Author |
n_TOF Collaboration (Tarrío, D. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Neutron-induced fission cross sections of Th-232 and U-233 up to 1 GeV using parallel plate avalanche counters at the CERN n_TOF facility |
Type |
Journal Article |
|
Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
|
Volume |
107 |
Issue |
4 |
Pages |
044616 - 21pp |
|
|
Keywords |
|
|
|
Abstract |
The neutron-induced fission cross sections of Th-232 and U-233 were measured relative to U-235 in a wide neutron energy range up to 1 GeV (and from fission threshold in the case of Th-232, and from 0.7 eV in case of U-233), using the white-spectrum neutron source at the CERN Neutron Time-of-Flight (nTOF) facility. Parallel plate avalanche counters (PPACs) were used, installed at the Experimental Area 1 (EAR1), which is located at 185 m from the neutron spallation target. The anisotropic emission of fission fragments were taken into account in the detection efficiency by using, in the case of U-233, previous results available in EXFOR, whereas in the case of Th-232 these data were obtained from our measurement, using PPACs and targets tilted 45 degrees with respect to the neutron beam direction. Finally, the obtained results are compared with past measurements and major evaluated nuclear data libraries. Calculations using the high-energy reaction models INCL++ and ABLA07 were performed and some of their parameters were modified to reproduce the experimental results. At high energies, where no other neutron data exist, our results are compared with experimental data on proton-induced fission. Moreover, the dependence of the fission cross section at 1 GeV with the fissility parameter of the target nucleus is studied by combining those ( p, f) data with our (n, f) data on Th-232 and U-233 and on other isotopes studied earlier at nTOF using the same experimental setup. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Tarrio, D.] Uppsala Univ, Dept Phys & Astron, Box 516, S-75120 Uppsala, Sweden, Email: diego.tarrio@physics.uu.se |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9985 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:001021341000001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
5618 |
|
Permanent link to this record |
|
|
|
|
Author |
n_TOF Collaboration (Tarrio, D. et al); Domingo-Pardo, C.; Plag, R.; Plompen, A.; Tain, J.L. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
High-energy Neutron-induced Fission Cross Sections of Natural Lead and Bismuth-209 |
Type |
Journal Article |
|
Year |
2011 |
Publication |
Journal of the Korean Physical Society |
Abbreviated Journal |
J. Korean Phys. Soc. |
|
|
Volume |
59 |
Issue |
2 |
Pages |
1904-1907 |
|
|
Keywords |
Nuclear data; Neutron-induced fission reactions; Pb-nat(n,f); Bi-209(n,f); Spallation neutron source; n_TOF facility |
|
|
Abstract |
The CERN Neutron Time-Of-Flight (n_TOF) facility is well suited to measure small neutron-induced fission cross sections, as those of subactinides. The cross section ratios of (nat)Pb and (209)Bi relative to (235)U and (238)U were measured using PPAC detectors. The fragment coincidence method allows to unambiguously identify the fission events. The present experiment provides the first results for neutron-induced fission up to 1 GeV for (nat)Pb and (209)Bi. A good agreement with previous experimental data below 200 MeV is shown. The comparison with proton-induced fission indicates that the limiting regime where neutron-induced and proton-induced fission reach equal cross section is close to 1 GeV. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Tarrio, D] Univ Santiago de Compostela, Fac Fis, Santiago De Compostela 15782, Spain, Email: diego.tarrio@usc.es |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Korean Physical Soc |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0374-4884 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000294080700109 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ elepoucu @ |
Serial |
739 |
|
Permanent link to this record |
|
|
|
|
Author |
BRIKEN Collaboration (Tolosa-Delgado, A. et al); Agramunt, J.; Tain, J.L.; Algora, A.; Domingo-Pardo, C.; Morales, A.I.; Rubio, B. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Commissioning of the BRIKEN detector for the measurement of very exotic beta-delayed neutron emitters |
Type |
Journal Article |
|
Year |
2019 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
|
|
Volume |
925 |
Issue |
|
Pages |
133-147 |
|
|
Keywords |
Beta-delayed neutrons; Neutron and beta counters; Analysis methodology; Background correction |
|
|
Abstract |
A new detection system has been installed at the RIKEN Nishina Center (Japan) to investigate decay properties of very neutron-rich nuclei. The setup consists of three main parts: a moderated neutron counter, a detection system sensitive to the implantation and decay of radioactive ions, and gamma-ray detectors. We describe here the setup, the commissioning experiment and some selected results demonstrating its performance for the measurement of half-lives and beta-delayed neutron emission probabilities. The methodology followed in the analysis of the data is described in detail. Particular emphasis is placed on the correction of the accidental neutron background. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Tolosa-Delgado, A.; Agramunt, J.; Tain, J. L.; Algora, A.; Domingo-Pardo, C.; Morales, A., I; Rubio, B.] CSIC, Inst Fis Corpuscular, E-46980 Paterna, Spain, Email: tain@ific.uv.es |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0168-9002 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000460539400018 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
3939 |
|
Permanent link to this record |
|
|
|
|
Author |
n_TOF Collaboration (Torres-Sanchez, P. et al); Babiano-Suarez, V.; Caballero, L.; Domingo-Pardo, C.; Ladarescu, I.; Tain, J.L. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Measurement of the 14N(n, p) 14C cross section at the CERN n_TOF facility from subthermal energy to 800 keV |
Type |
Journal Article |
|
Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
|
Volume |
107 |
Issue |
6 |
Pages |
064617 - 15pp |
|
|
Keywords |
|
|
|
Abstract |
Background: The 14N(n, p) 14C reaction is of interest in neutron capture therapy, where nitrogen-related dose is the main component due to low-energy neutrons, and in astrophysics, where 14N acts as a neutron poison in the s process. Several discrepancies remain between the existing data obtained in partial energy ranges: thermal energy, keV region, and resonance region. Purpose: We aim to measure the 14N(n, p) 14C cross section from thermal to the resonance region in a single measurement for the first time, including characterization of the first resonances, and provide calculations of Maxwellian averaged cross sections (MACS). Method: We apply the time-of-flight technique at Experimental Area 2 (EAR-2) of the neutron time-of-flight (n_TOF) facility at CERN. 10B(n, & alpha;) 7Li and 235U(n, f ) reactions are used as references. Two detection systems are run simultaneously, one on beam and another off beam. Resonances are described with the R-matrix code SAMMY. Results: The cross section was measured from subthermal energy to 800 keV, resolving the first two resonances (at 492.7 and 644 keV). A thermal cross section was obtained (1.809 & PLUSMN; 0.045 b) that is lower than the two most recent measurements by slightly more than one standard deviation, but in line with the ENDF/B-VIII.0 and JEFF-3.3 evaluations. A 1/v energy dependence of the cross section was confirmed up to tens of keV neutron energy. The low energy tail of the first resonance at 492.7 keV is lower than suggested by evaluated values, while the overall resonance strength agrees with evaluations. Conclusions: Our measurement has allowed determination of the 14N(n, p) cross section over a wide energy range for the first time. We have obtained cross sections with high accuracy (2.5%) from subthermal energy to 800 keV and used these data to calculate the MACS for kT = 5 to kT = 100 keV. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Torres-Sanchez, Pablo; Praena, Javier; Porras, Ignacio; Ogallar, Francisco] Univ Granada, Granada, Spain, Email: pablotorres@ugr.es |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9985 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:001063209900001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
5701 |
|
Permanent link to this record |
|
|
|
|
Author |
n_TOF Collaboration (Sosnin, N.V. et al.); Babiano-Suarez, V.; Caballero, L.; Domingo-Pardo, C.; Ladarescu, I.; Tain, J.L. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Measurement of the 77Se(n,gamma) cross section up to 200 keV at the n_TOF facility at CERN |
Type |
Journal Article |
|
Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
|
Volume |
107 |
Issue |
6 |
Pages |
065805 - 9pp |
|
|
Keywords |
|
|
|
Abstract |
The 77Se(n,gamma) reaction is of importance for 77Se abundance during the slow neutron capture process in massive stars. We have performed a new measurement of the 77Se radiative neutron capture cross section at the Neutron Time-of-Flight facility at CERN. Resonance capture kernels were derived up to 51 keV and cross sections up to 200 keV. Maxwellian-averaged cross sections were calculated for stellar temperatures between kT = 5 keV and kT = 100 keV, with uncertainties between 4.2% and 5.7%. Our results lead to substantial decreases of 14% and 19% in 77Se abundances produced through the slow neutron capture process in selected stellar models of 15M0 and 2M0, respectively, compared to using previous recommendation of the cross section. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[V. Sosnin, N.; Lederer-Woods, C.; Garg, R.; Dietz, M.; Murphy, A. St. J.; Lonsdale, S.; Woods, P. J.] Univ Edinburgh, Sch Phys & Astron, Edinburgh, Scotland, Email: nsosnin@ed.ac.uk |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9985 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:001023903800002 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
5599 |
|
Permanent link to this record |
|
|
|
|
Author |
n_TOF Collaboration (Weiss, C. et al); Domingo-Pardo, C.; Tain, J.L.; Tarifeño-Saldivia, A. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
The new vertical neutron beam line at the CERN n_TOF facility design and outlook on the performance |
Type |
Journal Article |
|
Year |
2015 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
|
|
Volume |
799 |
Issue |
|
Pages |
90-98 |
|
|
Keywords |
n_TOF facility; Neutron time-of-flight; FLUKA; Neutron cross-section measurement |
|
|
Abstract |
At the neutron Lime-of-flight facility n_TOF at CERN a new vertical beam line was constructed in 2014, in order to extend the experimental possibilities at this facility to an even wider range of challenging cross-section measurements of interest in astrophysics, nuclear technology and medical physics. The design of the beam line and the experimental hall was based on FLUKA Monte Carlo simulations, aiming at maximizing the neutron flux, reducing the beam halo and minimizing the background from neutrons interacting with the collimator or back-scattered in the beam dump. The present paper gives an overview on the design of the beam line and the relevant elements and provides an outlook on the expected performance regarding the neutron beam intensity, shape and energy resolution, as well as the neutron and photon backgrounds. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Weiss, C.; Chiaveri, E.; Girod, S.; Vlachoudis, V.; Aberle, O.; Bergstroem, I.; Calviani, M.; Guerrero, C.; Sabate-Gilarte, M.; Tsinganis, A.; Brugger, M.; Cerutti, F.; Ferrari, A.; Hernandez-Prieto, A.; Kadi, Y.; Leal-Cidoncha, E.; Losito, R.; Macina, D.; Montesano, S.; Porras, I.; Rubbia, C.] CERN, European Org Nucl Res, CH-1211 Geneva, Switzerland |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0168-9002 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000361877300015 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
2392 |
|
Permanent link to this record |
|
|
|
|
Author |
n_TOF Collaboration (Weiss, C. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
The (n,alpha) Reaction in the s-process Branching Point Ni-59 |
Type |
Journal Article |
|
Year |
2014 |
Publication |
Nuclear Data Sheets |
Abbreviated Journal |
Nucl. Data Sheets |
|
|
Volume |
120 |
Issue |
|
Pages |
208-210 |
|
|
Keywords |
|
|
|
Abstract |
The (n,alpha) reaction in the radioactive Ni-59 is of relevance in nuclear astrophysics as Ni-59 can be considered as the first branching point in the astrophysical s-process. Its relevance in nuclear technology is especially related to material embrittlement in stainless steel. However, there is a discrepancy between available experimental data and the evaluated nuclear data files for this reaction. At the n_TOF facility at CERN, a dedicated system based on sCVD diamond diodes was set up to measure the Ni-59(n,alpha)Fe-56 cross section. The results of this measurement, with special emphasis on the dominant resonance at 203 eV, are presented here. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Weiss, C.; Griesmayer, E.; Badurek, G.; Jericha, E.; Leeb, H.] Vienna Univ Technol, Atominst, Vienna, Austria, Email: christina.weiss@cern.ch |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Academic Press Inc Elsevier Science |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0090-3752 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000339860100058 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
1876 |
|
Permanent link to this record |
|
|
|
|
Author |
n_TOF Collaboration (Wright, T. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L.; Tarifeño-Saldivia, A. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Measurement of the U-238(n,gamma) cross section up to 80 keV with the Total Absorption Calorimeter at the CERN n_TOF facility |
Type |
Journal Article |
|
Year |
2017 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
|
Volume |
96 |
Issue |
6 |
Pages |
064601 - 11pp |
|
|
Keywords |
|
|
|
Abstract |
The radiative capture cross section of a highly pure (99.999%), 6.125(2) grams and 9.56(5) x 10(-4) atoms/barn areal density U-238 sample has been measured with the Total Absorption Calorimeter (TAC) in the 185 m flight path at the CERN neutron time-of-flight facility n_TOF. This measurement is in response to the NEA High Priority Request list, which demands an accuracy in this cross section of less than 3% below 25 keV. These data have undergone careful background subtraction, with special care being given to the background originating from neutrons scattered by the 238U sample. Pileup and dead-time effects have been corrected for. The measured cross section covers an energy range between 0.2 eV and 80 keV, with an accuracy that varies with neutron energy, being better than 4% below 25 keV and reaching at most 6% at higher energies. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Wright, T.; Billowes, J.; Ryan, J. A.; Ware, T.] Univ Manchester, Manchester, Lancs, England, Email: tobias.wright@manchester.ac.uk |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9985 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000416848700005 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
3392 |
|
Permanent link to this record |
|
|
|
|
Author |
n_TOF Collaboration (Wright, T. et al); Domingo-Pardo, C.; Tain, J.L. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Measurement of the prompt fission γ-rays from slow neutron-induced fission of 235U with STEFF |
Type |
Journal Article |
|
Year |
2024 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
|
|
Volume |
60 |
Issue |
3 |
Pages |
70 - 11pp |
|
|
Keywords |
|
|
|
Abstract |
The amount of energy carried by gamma-rays during the fission process is an important consideration when developing new reactor designs. Many studies of gamma-ray energy and multiplicity, from a multitude of fissioning systems, were measured during the 1970s. However the data from such experiments largely underestimates the heating effect caused by gamma-rays in the structure of a reactor. It is therefore essential to obtain more accurate measurements of the energy carried during gamma-ray emission. As such, the OECD Nuclear Energy Agency has put out a high priority request [1] for measurements of the mean gamma-ray energy and multiplicity to an accuracy better than 7.5 percent from several fissioning systems; including U-235(n(thermal)). Measurements of the rays from these fissioning nuclei were performed with the SpecTrometer for Exotic Fission Fagments (STEFF). |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Wright, T.; Smith, A. G.; Bennett, S. A.; Ryan, J. A.; Sekhar, A.; Warren, S.; Billowes, J.; Chiaveri, E.; Sabate-Gilarte, M.] Univ Manchester, Manchester, England, Email: tobias.wright@manchester.ac.uk |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1434-6001 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:001190743600002 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
6028 |
|
Permanent link to this record |
|
|
|
|
Author |
Yokoyama, R. et al; Tain, J.L.; Algora, A.; Agramunt, J.; Domingo-Pardo, C.; Morales, A.I.; Rubio, B.; Tolosa-Delgado, A. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title |
Strong one-neutron emission from two-neutron unbound states in beta decays of the r-process nuclei Ga-86,Ga-87 |
Type |
Journal Article |
|
Year |
2019 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
|
Volume |
100 |
Issue |
3 |
Pages |
031302 - 6pp |
|
|
Keywords |
|
|
|
Abstract |
beta-delayed one-neutron and two-neutron branching ratios (P-1n and P-2n) have been measured in the decay of A = 84 to 87 Ga isotopes at the Radioactive-Isotope Beam Factory (RIBF) at the RIKEN Nishina Center using a high-efficiency array of He-3 neutron counters (BRIKEN). Two-neutron emission was observed in the decay of Ga-84,Ga-85,Ga-87 for the first time and the branching ratios were measured to be P-2n = 1.6(2)%, 1.3(2)%, and 10.2(28)(stat)(5)(sys)%, respectively. One-neutron branching ratio of Ga-87 (P-1n = 81(9)(stat)(8)(sys)%) and half-life of 29(4) ms were measured for the first time. The branching ratios of Ga-86 were also measured to be P-1n = 74(2)(stat)(8)(sys)% and 16.2(9)(stat)(6)(sys)% with better precision than a previous study. The observation that P-1n > P-2n for both Ga-86,Ga-87 was unexpected and is interpreted as a signature of dominating one-neutron emission from the two-neutron unbound excited states in Ge-86,Ge-87. In order to interpret the experimental results, shell-model and Hauser-Feshbach statistical model calculations of delayed particle and gamma-ray emission probabilities were performed. This model framework reproduces the experimental results. The shell model alone predicts P-2n significantly larger than P-1n for the Ga-87 decay, and it is necessary to invoke a statistical description to successfully explain the observation that P-1n > P-2n. Our new results demonstrate the relevance and importance of a statistical description of neutron emission for the prediction of the decay properties of multineutron emitters and that it must be included in the r-process modeling. |
|
|
Address ![sorted by Address field, ascending order (up)](img/sort_asc.gif) |
[Yokoyama, R.; Grzywacz, R.; Rasco, B. C.; Brewer, N.; Heideman, J.; King, T. T.; Madurga, M.; Singh, M.] Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA, Email: ryokoyam@utk.edu |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9985 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000486641000001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4145 |
|
Permanent link to this record |