Records |
Author |
Gjestvang, D. et al; Algora, A. |
Title |
Examination of how properties of a fissioning system impact isomeric yield ratios of the fragments |
Type |
Journal Article |
Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
108 |
Issue |
6 |
Pages |
064602 - 12pp |
Keywords |
|
Abstract |
The population of isomeric states in the prompt decay of fission fragments-so-called isomeric yield ratios (IYRs)-is known to be sensitive to the angular momentum J that the fragment emerged with, and may therefore contain valuable information on the mechanism behind the fission process. In this work, we investigate how changes in the fissioning system impact the measured IYRs of fission fragments to learn more about what parameters affect angular momentum generation. To enable this, a new technique for measuring IYRs is first demonstrated. It is based on the time of arrival of discrete gamma rays, and has the advantage that it enables the study of the IYR as a function of properties of the partner nucleus. This technique is used to extract the IYR of 134Te, strongly populated in actinide fission, from the three different fissioning systems: 232Th(n, f), 238U(n, f), at two different neutron energies, as well as 252Cf(sf). The impacts of changing the fissioning system, the compound nuclear excitation energy, the minimum J of the binary partner, and the number of neutrons emitted on the IYR of 134Te are determined. The decay code TALYS is used in combination with the fission simulation code FREYA to calculate the primary fragment angular momentum from the IYR. We find that the IYR of 134Te has a slope of 0.004 +/- 0.002 with increase in compound nucleus (CN) mass. When investigating the impact on the IYR of increased CN excitation energy, we find no change with an energy increase similar to the difference between thermal and fast fission. By varying the mass of the partner fragment emerging with 134Te, it is revealed that the IYR of 134Te is independent of the total amount of prompt neutrons emitted from the fragment pair. This indicates that neutrons carry minimal angular momentum away from the fission fragments. Comparisons with the FREYA+TALYS simulations reveal that the average angular momentum in 134Te following 238U(n, f) is 6.0 h over bar . This is not consistent with the value deduced from recent CGMF calculations. Finally, the IYR sensitivity to the angular momentum of the primary fragment is discussed. These results are not only important to help understanding the underlying mechanism in nuclear fission, but can also be used to constrain and benchmark fission models, and are relevant to the gamma -ray heating problem of reactors. |
Address |
[Gjestvang, D.; Siem, S.; Nemer, J.; Paulsen, W.; Popovitch, Y.] Univ Oslo, Dept Phys, N-0316 Oslo, Norway, Email: dorthea.gjestvang@fys.uio.no |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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English |
Summary Language |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9985 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001160674400006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5947 |
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Author |
Jungclaus, A. et al; Montaner-Piza, A. |
Title |
Evolution of proton single-particle states in neutron-rich Sb isotopes beyond N=82 |
Type |
Journal Article |
Year |
2020 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
102 |
Issue |
3 |
Pages |
034324 - 11pp |
Keywords |
|
Abstract |
The beta decay of the semimagic Sn isotopes Sn-136,Sn-137,Sn-138 has been studied at the Radioactive Isotope Beam Factory at the RIKEN Nishina Center. The first experimental information on excited states was obtained for Sb-137 while, in the case of Sb-136, the established excitation scheme could be extended by ten previously unidentified levels. In the decay of the most-neutron-rich isotope Sn-138, two gamma rays were observed for the first time. The new experimental results, in combination with state-of-the-art shell-model calculations, provide the first information with respect to the evolution of the Og(7/2) and 1d(5/2) proton single-particle states with increasing neutron number beyond N = 84. |
Address |
[Jungclaus, A.; Taprogge, J.] CSIC, Inst Estruct Mat, E-28006 Madrid, Spain, Email: andrea.jungclaus@csic.es |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0556-2813 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000575177000001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4561 |
Permanent link to this record |
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Author |
IDS Collaboration (Lica, R. et al); Morales, A.I. |
Title |
Evolution of deformation in neutron-rich Ba isotopes up to A=150 |
Type |
Journal Article |
Year |
2018 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
97 |
Issue |
2 |
Pages |
024305 - 12pp |
Keywords |
|
Abstract |
The occurrence of octupolar shapes in the Ba isotopic chain was recently established experimentally up to N = 90. To further extend the systematics, the evolution of shapes in the most neutron-rich members of the Z = 56 isotopic chain accessible at present, Ba-148,Ba-150, has been studied via beta decay at the ISOLDE Decay Station. This paper reports on the first measurement of the positive-and negative-parity low-spin excited states of 150Ba and presents an extension of the beta-decay scheme of Cs-148. Employing the fast timing technique, half-lives for the 2(1)(+) level in both nuclei have been determined, resulting in T-1/2 = 1.51(1) ns for Ba-148 and T-1/2 = 3.4(2) ns for Ba-150. The systematics of low-spin states, together with the experimental determination of the B(E2 : 2(+) -> 0(+)) transition probabilities, indicate an increasing collectivity in Ba148-150, towards prolate deformed shapes. The experimental data are compared to symmetry conserving configuration mixing (SCCM) calculations, confirming an evolution of increasingly quadrupole deformed shapes with a definite octupolar character. |
Address |
[Lica, R.; Borge, M. J. G.; Madurga, M.; Kurcewicz, J.; Rapisarda, E.] CERN, ISOLDE EP, CH-1211 Geneva 23, Switzerland, Email: giovanna.benzoni@mi.infn.it |
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Amer Physical Soc |
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English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9985 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000424089400005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3471 |
Permanent link to this record |
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Author |
IDS Collaboration (Heideman, J. et al); Algora, A.; Morales, A.I. |
Title |
Evidence of nonstatistical neutron emission following beta decay near doubly magic Sn-132 |
Type |
Journal Article |
Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
108 |
Issue |
2 |
Pages |
024311 - 9pp |
Keywords |
|
Abstract |
Models of the beta-delayed neutron emission (beta n) assume that neutrons are emitted statistically via an intermediate compound nucleus post beta decay. Evidence to the contrary was found in an In-134 beta-decay experiment carried out at ISOLDE CERN. Neutron emission probabilities from the unbound states in Sn-134 to known low-lying, single-particle states in Sn-133 were measured. The neutron energies were determined using the time-of-flight technique, and the subsequent decay of excited states in Sn-133 was studied using gamma-ray detectors. Individual beta n probabilities were determined by correlating the relative intensities and energies of neutrons and gamma rays. The experimental data disagree with the predictions of representative statistical models which are based upon the compound nucleus postulate. Our results suggest that violation of the compound nucleus assumption may occur in beta-delayed neutron emission. This impacts the neutron-emission probabilities and other properties of nuclei participating in the r-process. A model of neutron emission, which links the observed neutron emission probabilities to nuclear shell effects, is proposed. |
Address |
[Heideman, J.; Grzywacz, R.; Xu, Z. Y.; Madurga, M.; Halverson, C.; King, T. T.; Singh, M.; Yokoyama, R.] Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA |
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Amer Physical Soc |
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English |
Summary Language |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9985 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001053419100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5620 |
Permanent link to this record |
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Author |
AGATA Collaboration (Liu, X. et al); Gadea, A.; Jurado, M.; Domingo-Pardo, C.; Huyuk, T.; Perez-Vidal, R.M. |
Title |
Evidence for spherical-oblate shape coexistence in Tc-87 |
Type |
Journal Article |
Year |
2022 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
106 |
Issue |
3 |
Pages |
034304 - 6pp |
Keywords |
|
Abstract |
Excited states in the neutron-deficient nucleus Tc-87 have been studied via the fusion-evaporation reaction 54Fe(36Ar, 2n1p) Tc-87 at 115 MeV beam energy. The AGATA gamma-ray spectrometer coupled to the DIAMANT, NEDA, and Neutron Wall detector arrays for light-particle detection was used to measure the prompt coincidence of gamma rays and light particles. Six transitions from the deexcitation of excited states belonging to a new band in Tc-87 were identified by comparing gamma-ray intensities in the spectra gated under different reaction channel selection conditions. The constructed level structure was compared with the shell model and total Routhian surface calculations. The results indicate that the new band structure in 87Tc is built on a spherical configuration, which is different from that assigned to the previously identified oblate yrast rotational band. |
Address |
[Liu, X.; Cederwall, B.; Qi, C.; Wyss, R. A.; Aktas, O.; Ertoprak, A.; Zhang, W.; Nyberg, A. Atac; Back, T.] Royal Inst Technol, Dept Phys, S-10405 Stockholm, Sweden, Email: xiaoyuli@kth.se |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9985 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000863087400003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5373 |
Permanent link to this record |
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Author |
AGATA Collaboration (Liu, X. et al); Gadea, A.; Jurado, M.; Domingo-Pardo, C.; Huyuk, T.; Perez-Vidal, R.M. |
Title |
Evidence for enhanced neutron-proton correlations from the level structure of the N = Z+1 nucleus Tc-87(43)44 |
Type |
Journal Article |
Year |
2021 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
104 |
Issue |
2 |
Pages |
L021302 - 5pp |
Keywords |
|
Abstract |
The low-lying excited states in the neutron-deficient N = Z + 1 nucleus (87)(43)Tcc(44) have been studied via the fusion-evaporation reaction Fe-54(Ar-36, 2n1p)Tc-87 at the Grand Accelerateur National d'Ions Lourds (GANIL), France. The AGATA spectrometer was used in conjunction with the auxiliary NEDA, Neutron Wall, and DIAMANT detector arrays to measure coincident prompt gamma rays, neutrons, and charged particles emitted in the reaction. A level scheme of Tc-87 from the (9/2(g.s.)(+)) state to the (33/2(1)(+)) state was established based on six mutually coincident gamma-ray transitions. The constructed level structure exhibits a rotational behavior with a sharp backbending at (h) over bar omega approximate to 0.50 MeV. A decrease in alignment frequency and increase in alignment sharpness in the odd-mass isotonic chains around N = 44 is proposed as an effect of the enhanced isoscalar neutron-proton interactions in odd-mass nuclei when approaching the N = Z line. |
Address |
[Liu, X.; Cederwall, B.; Qi, C.; Wyss, R. A.; Aktas, O.; Ertoprak, A.; Zhang, W.; Nyberg, A. Atac; Back, T.] Royal Inst Technol, Dept Phys, S-10405 Stockholm, Sweden, Email: xiaoyuli@kth.se |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9985 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000686912200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4942 |
Permanent link to this record |
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Author |
Bayar, M.; Xiao, C.W.; Hyodo, T.; Dote, A.; Oka, M.; Oset, E. |
Title |
Energy and width of a narrow I=1/2 DNN quasibound state |
Type |
Journal Article |
Year |
2012 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
86 |
Issue |
4 |
Pages |
044004 - 16pp |
Keywords |
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Abstract |
The energies and widths of DNN quasibound states with isospin I = 1/2 are evaluated in two methods, the fixed center approximation to the Faddeev equation and the variational method approach to the effective one-channel Hamiltonian. The DN interactions are constructed so they dynamically generate the Lambda(c)(2595) (I = 0, J(pi) = 1/2(-)) resonance state. We find that the system is bound by about 250 MeV from the DNN threshold, root s similar to 3500 MeV. Its width, including both the mesonic decay and the D absorption, is estimated to be about 20-40 MeV. The I = 0 DN pair in the DNN system is found to form a cluster that is similar to the Lambda(c)(2595). |
Address |
[Bayar, M.; Xiao, C. W.; Oset, E.] Ctr Mixto Univ Valencia CSIC, Inst Invest Paterna, Dept Fis Teor, Valencia 46071, Spain |
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Amer Physical Soc |
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English |
Summary Language |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0556-2813 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000310436100003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1197 |
Permanent link to this record |
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Author |
TAPS Collaboration; Piasecki, K.; Matulewicz, T.; Yahlali, N.; Delagrange, H.; Diaz, J.; d'Enterria, D.G.; Fernandez, F.; Kugler, A.; Lohner, H.; Martinez-Garcia, G.; Ostendorf, R.W.; Schutz, Y.; Tlusty, P.; Turrisi, R.; Wagner, V.; Wilschut, H.W. |
Title |
Emission patterns of neutral pions in 40A MeV Ta plus Au reactions |
Type |
Journal Article |
Year |
2010 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
81 |
Issue |
5 |
Pages |
054912 - 7pp |
Keywords |
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Abstract |
Differential cross sections of neutral pions emitted in Ta-181+Au-197 collisions at a beam energy of 39.5A Me V have been measured with the two-arm photon spectrometer (TAPS). The kinetic energy and transverse momentum spectra of neutral pions cannot be properly described in the framework of the thermal model, nor when the reabsorption of pions is accounted for in a phenomenological model. However, high energy and high momentum tails of the pion spectra can be well fitted through thermal distributions with unexpectedly soft temperature parameters below 10 MeV. |
Address |
[Piasecki, K.; Matulewicz, T.] Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland, Email: Krzysztof.Piasecki@fuw.edu.pl |
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Publisher |
Amer Physical Soc |
Place of Publication |
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English |
Summary Language |
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Series Editor |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0556-2813 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000278144800055 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
442 |
Permanent link to this record |
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Author |
Wrede, C.; Sjue, S.K.L.; Garcia, A.; Swanson, H.E.; Ahmad, I.; Algora, A.; Elomaa, V.V.; Eronen, T.; Hakala, J.; Jokinen, A.; Kolhinen, V.S.; Moore, I.D.; Penttila, H.; Reponen, M.; Rissanen, J.; Saastamoinen, A.; Aysto, J. |
Title |
Electron capture on In-116 and implications for nuclear structure related to double-beta decay |
Type |
Journal Article |
Year |
2013 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
87 |
Issue |
3 |
Pages |
031303 - 5pp |
Keywords |
|
Abstract |
The electron capture decay branch of In-116 has been measured to be [2.46 +/- 0.44(stat.) +/- 0.39(syst.)] x 10(-4) using Penning trap-assisted decay spectroscopy. The corresponding Gamow-Teller transition strength is shown to be compatible with the most recent value extracted from the (p, n) charge-exchange reaction, providing a resolution to longstanding discrepancies. This transition can now be used as a reliable benchmark for nuclear-structure calculations of the matrix element for the neutrinoless double-beta decay of Cd-116 and other nuclides. |
Address |
[Wrede, C.; Garcia, A.; Swanson, H. E.] Univ Washington, Dept Phys, Seattle, WA 98195 USA, Email: wrede@nscl.msu.edu |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Series Editor |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
0556-2813 |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000315735100002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1348 |
Permanent link to this record |
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Author |
Alharbi, T. et al; Algora, A. |
Title |
Electromagnetic transition rates in the N=80 nucleus Ce-138(58) |
Type |
Journal Article |
Year |
2013 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
87 |
Issue |
1 |
Pages |
014323 - 7pp |
Keywords |
|
Abstract |
The half-life of the I-pi = 6(+) yrast state at E-x = 2294 keV in Ce-138 has been measured as T-1/2 = 880(19) ps using the fast-timing gamma-ray coincidence method with a mixed LaBr3(Ce)-HPGe array. The excited states in Ce-138 have been populated by the Te-130(C-12, 4n) fusion-evaporation reaction at an incident beam energy of 56 MeV. The extracted B(E2; 6(1)(+) -> 4(1)(+)) = 0.101(24) W.u. value is compared with the predictions of truncated basis shell model calculations and with the systematics of the region. This shows an anomalous behavior compared to the neighboring isotonic and isotopic chains. Half-lives for the yrast 5(-), 11(+) and 14(+) states in Ce-138 have also been determined in this work. |
Address |
[Alharbi, T.; Regan, P. H.; Mason, P. J. R.; Podolyak, Zs; Simpson, E. C.; Alazemi, N.; Britton, R.; Bunce, M. R.; Gelletly, W.; Lintott, J.; Nakhostin, M.; Rice, S.; Townsley, C.; Wilson, E.] Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England |
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Publisher |
Amer Physical Soc |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0556-2813 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000313751800002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1312 |
Permanent link to this record |