Author: "Stanoiu, M." / Database: OpenAIRE - Searchworks@Jio Institute Digital Library Search Results

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203 results on '"Stanoiu, M."'

1. Neutron-proton pairing in the N=Z radioactive -shell Nuclei Ni and Fe probed by pair transfer

Author: Le Crom, B., Assié, M., Blumenfeld, Y., Guillot, J., Sagawa, H., Suzuki, T., Honma, M., Achouri, N.L., Bastin, B., Borcea, R., Catford, W.N., Clément, E., Cáceres, L., Caamaño, M., Corsi, A., De France, G., Delaunay, F., De Séréville, N., Fernandez-Dominguez, B., Fisichella, M., Franchoo, S., Georgiadou, A., Gibelin, J., Gillibert, A., Hammache, F., Kamalou, O., Knapton, A., Lapoux, V., Leblond, S., Macchiavelli, A.O., Marqués, F.M., Matta, A., Ménager, L., Morfouace, P., Orr, N.A., Pancin, J., Pereira-Lopez, X., Perrot, L., Piot, J., Pollacco, E., Ramos, D., Roger, T., Rotaru, F., Sánchez-Benítez, A.M., Sénoville, M., Sorlin, O., Stanoiu, M., Stefan, I., Stodel, C., Suzuki, D., Thomas, J.C., and Vandebrouck, M.
Abstract: The isovector and isoscalar components of neutron-proton pairing are investigated in the N=Z unstable nuclei of the fp-shell through the two-nucleon transfer reaction (p,$^{3}$He) in inverse kinematics. The combination of particle and gamma-ray detection with radioactive beams of $^{56}$Ni and $^{52}$Fe, produced by fragmentation at the GANIL/LISE facility, made it possible to carry out this study for the first time in a closed and an open-shell nucleus in the fp-shell. The transfer cross-sections for ground-state to ground-state (J=0$^{+}$, T=1) and to the first (J=1$^{+}$, T=0) state were extracted for both cases together with the transfer cross-section ratios σ(0+,T=1)/σ(1+,T=0). They are compared with second-order distorted-wave born approximation (DWBA) calculations. The enhancement of the ground-state to ground-state pair transfer cross-section close to mid-shell, in $^{52}$Fe, points towards a superfluid phase in the isovector channel. For the “deuteron-like” transfer, very low cross-sections to the first (J=1$^{+}$, T=0) state were observed both for $^{56}$Ni(p,$^{3}$He) and $^{52}$Fe(p,$^{3}$He) and are related to a strong hindrance of this channel due to spin-orbit effect. No evidence for an isoscalar deuteron-like condensate is observed.
Published: 2023

2. Suppression of Coulomb-nuclear interference in the near-barrier elastic scattering of Ne from Pb

Author: Ovejas, J.D., Martel, I., Dell'Aquila, D., Acosta, L., Aguado, J.L., de Angelis, G., Borge, M.J.G., Briz, J.A., Chbihi, A., Colucci, G., Díaz-Martín, C., Figuera, P., Galaviz, D., García-Ramos, C., Gómez-Galán, J.A., Gonzales, C.A., Goyal, N., Keeley, N., Kemper, K.W., Kurtukian Nieto, T., Malenica, D.J., Mazzocco, M., Nurkić, D., Orduz, A.K., Ortiz, A., Palada, L., Parascandolo, C., Di Pietro, A., Rodriguez, A.M., Rusek, K., Salguero, F., Sánchez-Benítez, A.M., Sánchez-Raya, M., Sánchez-Segovia, J., Soić, N., Soramel, F., Stanoiu, M., Tengblad, O., Vukman, N., and Xarepe, M.
Abstract: The proton drip-line nucleus $^{17}$Ne is considered a good candidate for a Borromean two-proton halo with a $^{15}$O + p + p structure. Angular distributions of the elastic scattering and inclusive $^{15}$O production for a 136 MeV $^{17}$Ne beam incident on a $^{208}$Pb target were measured for the first time at the SPIRAL1 facility, GANIL. Use of the GLORIA detector array allowed high-resolution data over a wide angular range from 20∘ up to 95∘ in the laboratory frame to be obtained. The elastic scattering angular distribution shows similarities with those for both $^{6}$He and $^{20}$Ne at equivalent collision energies with respect to the corresponding Coulomb barriers, exhibiting the suppression of the Coulomb rainbow peak characteristic of strong coupling. Optical model and coupled channel fits suggest that this is due to a combination of coupling to low-lying quadrupole resonances and Coulomb dipole coupling to the low-lying continuum, although their relative importance depends on the relevant B(E2) values which remain to be firmly determined.
Published: 2023

3. Suppression of Coulomb-nuclear interference in the near-barrier elastic scattering of $^{17}$Ne from$^{208}$Pb

Author: Díaz-Ovejas, J, Martel, I, Dell'Aquila, D, Acosta, L, Aguado, J.L, de Angelis, G, Borge, M.J.G, Briz, J.A, Chbihi, A, Colucci, G, Díaz-Martín, C, Figuera, P, Galaviz, D, García-Ramos, C, Gómez-Galán, J.A, Gonzales, C.A, Goyal, N, Keeley, N, Kemper, K.W, Kurtukian Nieto, T, Malenica, D.J, Mazzocco, M, Nurkić, D, Orduz, A.K, Ortiz, A, Palada, L, Parascandolo, C, Di Pietro, A, Rodriguez, A.M, Rusek, K, Salguero, F, Sánchez-Benítez, A.M, Sánchez-Raya, M, Sánchez-Segovia, J, Soić, N, Soramel, F, Stanoiu, M, Tengblad, O, Vukman, N, Xarepe, M, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Optical model, Elastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Direct nuclear reactions, Radioactive beams
Abstract: International audience; The proton drip-line nucleus 17Ne is considered a good candidate for a Borromean two-proton halo with a 15O + p + p structure. Angular distributions of the elastic scattering and inclusive 15O production for a 136 MeV 17Ne beam incident on a 208Pb target were measured for the first time at the SPIRAL1 facility, GANIL. Use of the GLORIA detector array allowed high-resolution data over a wide angular range from 20∘ up to 95∘ in the laboratory frame to be obtained. The elastic scattering angular distribution shows similarities with those for both 6He and 20Ne at equivalent collision energies with respect to the corresponding Coulomb barriers, exhibiting the suppression of the Coulomb rainbow peak characteristic of strong coupling. Optical model and coupled channel fits suggest that this is due to a combination of coupling to low-lying quadrupole resonances and Coulomb dipole coupling to the low-lying continuum, although their relative importance depends on the relevant B(E2) values which remain to be firmly determined.
Published: 2023

4. Cross-shell states in $^{15}$C: a test for p-sd interactions

Author: Lois-Fuentes, J., Fernandez-Dominguez, B., Pereira-Lopez, X., Delaunay, F., Catford, W.N., Matta, A., Orr, N.A., Duguet, T., Otsuka, T., Soma, V., Sorlin, O., Suzuki, T., Achouri, N.L., Assie, M., Bailey, S., Bastin, B., Blumenfeld, Y., Borcea, R., Caamano, M., Caceres, L., Clement, E., Corsi, A., Curtis, N., Deshayes, Q., Farget, F., Fisichella, M., de France, G., Franchoo, S., Freer, M., Gibelin, J., Gillibert, A., Grinyer, G.F., Hammache, F., Kamalou, O., Knapton, A., Kokalova, Tz., Lapoux, V., Le Crom, B., Leblond, S., Marques, F.M., Morfouace, P., Pancin, J., Perrot, L., Piot, J., Pollacco, E., Ramos, D., Regueira-Castro, D., Rodriguez-Tajes, C., Roger, T., Rotaru, F., Senoville, M., de Sereville, N., Smith, R., Stanoiu, M., Stefan, I., Stodel, C., Suzuki, D., Thomas, J.C., Timofeyuk, N., Vandebrouck, M., Walshe, J., Wheldon, C., Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear Theory (nucl-th), [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Nuclear Theory, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: International audience; The low-lying structure of $^{15}$C has been investigated via the neutron-removal $^{16}$C$(d,t)$ reaction. Along with bound neutron sd-shell hole states, unbound p-shell hole states have been firmly confirmed. The excitation energies and the deduced spectroscopic factors of the cross-shell states are an important measure of the $[(p)^{-1}(sd)^{2}]$ neutron configurations in $^{15}$C. Our results show a very good agreement with shell-model calculations using the SFO-tls interaction for $^{15}$C. However, a modification of the $p$-$sd$ and $sd$-$sd$ monopole terms was applied in order to reproduce the $N=9$ isotone $^{17}$O. In addition, the excitation energies and spectroscopic factors have been compared to the first calculations of $^{15}$C with the $ab~ initio$ self-consistent Green's function method employing the NNLO$_{sat}$ interaction. The results show the sensitivity to the size of the $N=8$ shell gap and highlight the need of going beyond the current truncation scheme in the theory.
Published: 2023
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5. Data for publication in Nature Communications: Search for 22Na in novae supported by a novel method for measuring femtosecond nuclear lifetimes

Author: Fougères, C., Oliveira Santos, F., José, J., Michelagnoli, C., Clément, E., Kim, Y. H., Lemasson, A., Guimarães, V., Barrientos, D., Bemmerer, D., Benzoni, G., Boston, A. J., Böttger, R., Boulay, F., Bracco, A., Celikovic, I., Cederwall, B., Ciemala, M., Delafosse, C., Domingo-Pardo, C., Dudouet, J., Eberth, J., Fülöp, Z., González, V., Gottardo, A., Goupil, J., Hess, H., Jungclaus, A., Kaskas, A., Korichi, A., Lenzi, S. M., Leoni, S., Li, H., Ljungvall, J., Lopez-Martens, A., Menegazzo, R., Mengoni, D., Million, B., Mrazek, J., Napoli, D. R., Navin, A., Nyberg, J., Podolyak, Z., Pullia, A., Quintana, B., Ralet, D., Redon, N., Reiter, P., Rezynkina, K., Saillant, F., Salsac, M. D., Sánchez-Benítez, A. M., Sanchis, E., Senyigit, M., Siciliano, M., Smirnova, N. A., Sohler, D., Stanoiu, M., Theisen, C., Valiente-Dobón, J. J., Ujic, P., and Zielinska, M.
Abstract: https://u.ganil-spiral2.eu/10.26143/GANIL-2016-E710.html
Published: 2023

6. γ decay to the ground state from the excitations above the neutron threshold in the 208Pb(p,p'γ) reaction at 85 MeV

Author: Wasilewska, B., Kmiecik, M., Ciemała, M., Maj, A., Crespi, F. C.L., Bracco, A., Harakeh, M. N., Bednarczyk, P., Bottoni, S., Brambilla, S., Camera, F., Ciepał, I., Cieplicka-Oryńczak, N., Csatlos, M., Fornal, B., Gaudilla, V., Grȩbosz, J., Isaak, J., Iskra, W., Jeżabek, M., Krasznahorkay, A. J., Kihel, S., Krzysiek, M., Lasko, P., Leoni, S., Lewitowicz, M., Łukasik, J., Matejska-Minda, M., Mazurek, K., Napiorkowski, P. J., Parol, W., Pawłowski, P., Qi, L. Q., Saxena, M., Schmitt, Ch, Sobolev, Y., Sowicki, B., Stanoiu, M., Tamii, A., Wieland, O., and Ziȩbliński, M.
Abstract: A new measurement of γ decay from the states above the neutron threshold in Pb208 has been performed at Cyclotron Centre Bronowice in Kraków, Poland. The main goal of the experiment was to observe the γ decay to the ground state from the isoscalar giant quadrupole resonance (ISGQR). To this day, the only published observation of this phenomenon dates back to the late 1980s, where γ decay to the ground state branching ratio was reported. At variance with the existing measurement using inelastic scattering of O17, here proton inelastic scattering is employed. In particular, data were obtained for Pb208(p,p′γ) at 85 MeV beam energy, where γ rays were measured for proton scattering angles 8.9∘, 10.7∘, 12.5∘, and 14.3∘. By applying a similar analysis method as in the previous experiment, the branching ratio of ISGQR gamma decay to the ground state was extracted from the data.
Published: 2022

7. New narrow resonances observed in the unbound nucleus F 15

Author: Girard-Alcindor, V., Mercenne, A., Stefan, I., De Oliveira Santos, F., Michel, N., Ploszajczak, M., Assie, M., Lemasson, A., Clement, E., Flavigny, F., Matta, A., Ramos, D., Rejmund, M., Dudouet, J., Ackermann, D., Adsley, P., Assuncao, M., Bastin, B., Beaumel, D., Benzoni, G., Borcea, R., Boston, A. J., Brugnara, D., Caceres, L., Cederwall, B., Celikovic, I., Chudoba, V., Ciemala, M., Collado, J., Crespi, F. C. L., D'Agata, G., De France, G., Delaunay, F., Diget, C., Domingo-Pardo, C., Eberth, J., Fougeres, C., Franchoo, S., Galtarossa, F., Georgiadou, A., Gibelin, J., Giraud, S., Gonzalez, V., Goyal, N., Gottardo, A., Goupil, J., Grevy, S., Guimaraes, V., Hammache, F., Harkness-Brennan, L. J., Hess, H., Jovancevic, N., Judson Oliver, D. S., Kamalou, O., Kamenyero, A., Kiener, J., Korten, W., Koyama, S., Labiche, M., Lalanne, L., Lapoux, V., Leblond, S., Lefevre, A., Lenain, C., Leoni, S., Li, H., Lopez-Martens, A., Maj, A., Matea, I., Menegazzo, R., Mengoni, D., Meyer, A., Million, B., Monteagudo, B., Morfouace, P., Mrazek, J., Niikura, M., Piot, J., Podolyak, Z., Portail, C., Pullia, A., Quintana, B., Recchia, F., Reiter, P., Rezynkina, K., Roger, T., Rojo, J. S., Rotaru, F., Salsac, M. D., Sanchez Benitez, A. M., Sanchis, E., Senyigit, M., De Sereville, N., Siciliano, M., Simpson, J., Sohler, D., Sorlin, O., Stanoiu, M., Stodel, C., Suzuki, D., Theisen, C., Thisse, D., C. thomas J., Ujic, P., Valiente-Dobon, J. J., and Zielinska, M.
Published: 2022

8. New narrow resonances observed in the unbound nucleus <math><mmultiscripts><mi mathvariant='normal'>F</mi><mprescripts/><none/><mn>15</mn></mmultiscripts></math>

Author: Girard-Alcindor, V., Mercenne, A., Stefan, I., de Oliveira Santos, F., Michel, N., Płoszajczak, M., Assié, M., Lemasson, A., Clément, E., Flavigny, F., Matta, A., Ramos, D., Rejmund, M., Dudouet, J., Ackermann, D., Adsley, P., Assunção, M., Bastin, B., Beaumel, D., Benzoni, G., Borcea, R., Boston, A.J., Cáceres, L., Cederwall, B., Celikovic, I., Chudoba, V., Ciemala, M., Collado, J., Crespi, F.C.L., d'Agata, G., de France, G., Delaunay, F., Diget, C., Domingo-Pardo, C., Eberth, J., Fougères, C., Franchoo, S., Galtarossa, F., Georgiadou, A., Gibelin, J., Giraud, S., González, V., Goyal, N., Gottardo, A., Goupil, J., Grévy, S., Guimaraes, V., Hammache, F., Harkness-Brennan, L.J., Hess, H., Oliver, D.S. Judson, Kamalou, O., Kameneyero, A., Kiener, J., Korten, W., Koyama, S., Labiche, M., Lalanne, L., Lapoux, V., Leblond, S., Lefevre, A., Lenain, C., Leoni, S., Li, H., Lopez-Martens, A., Maj, A., Matea, I., Menegazzo, R., Mengoni, D., Meyer, A., Million, B., Monteagudo, B., Morfouace, P., Mrazek, J., Niikura, M., Piot, J., Podolyak, Zs., Portail, C., Pullia, A., Quintana, B., Recchia, F., Reiter, P., Rezynkina, K., Roger, T., Rojo, J.S., Rotaru, F., Salsac, M.D., Benitez, A.M. Sánchez, Sanchis, E., Şenyigit, M., de Séréville, N., Siciliano, M., Simpson, J., Sohler, D., Sorlin, O., Stanoiu, M., Stodel, C., Suzuki, D., Theisen, C., Thomas, J.C., Ujic, P., Valiente-Dobón, J.J., Zielińska, M., Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and ANR-17-CE31-0026,OASIS,Optimisation d'Agata pour la physique(2017)
Subjects: [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Abstract: International audience; The structure of the unbound F15 nucleus is investigated using the inverse kinematics resonant scattering of a radioactive O14 beam impinging on a CH2 target. The analysis of H1(O14,p)O14 and H1(O14,2p)N13 reactions allowed the confirmation of the previously observed narrow 1/2− resonance, near the two-proton decay threshold, and the identification of two new narrow 5/2− and 3/2− resonances. The newly observed levels decay by 1p emission to the ground of O14, and by sequential 2p emission to the ground state of N13 via the 1− resonance of O14. Gamow shell model (GSM) analysis of the experimental data suggests that the wave functions of the 5/2− and 3/2− resonances may be collectivized by the continuum coupling to nearby 2p- and 1p-decay channels. The observed excitation function H1(O14,p)O14 and resonance spectrum in F15 are well reproduced in the unified framework of the GSM.
Published: 2022

9. Narrow resonances in the continuum of the unbound nucleus $^{15}$F

Author: Girard-Alcindor, V., Mercenne, A., Stefan, I., de Oliveira Santos, F., Michel, N., Płoszajczak, M., Assié, M., Lemasson, A., Clément, E., Flavigny, F., Matta, A., Ramos, D., Rejmund, M., Dudouet, J., Ackermann, D., Adsley, P., Assunção, M., Bastin, B., Beaumel, D., Benzoni, G., Borcea, R., Boston, A.J., Cáceres, L., Cederwall, B., Celikovic, I., Chudoba, V., Ciemala, M., Collado, J., Crespi, F.C.L., D'Agata, G., De France, G., Delaunay, F., Diget, C., Domingo-Pardo, C., Eberth, J., Fougères, C., Franchoo, S., Galtarossa, F., Georgiadou, A., Gibelin, J., Giraud, S., González, V., Goyal, N., Gottardo, A., Goupil, J., Grévy, S., Guimaraes, V., Hammache, F., Harkness-Brennan, L.J., Hess, H., Oliver, D.S. Judson, Kamalou, O., Kameneyero, A., Kiener, J., Korten, W., Koyama, S., Labiche, M., Lalanne, L., Lapoux, V., Leblond, S., Lefevre, A., Lenain, C., Leoni, S., Li, H., Lopez-Martens, A., Maj, A., Matea, I., Menegazzo, R., Mengoni, D., Meyer, A., Million, B., Monteagudo, B., Morfouace, P., Mrazek, J., Niikura, M., Piot, J., Podolyak, Zs., Portail, C., Pullia, A., Quintana, B., Recchia, F., Reiter, P., Rezynkina, K., Roger, T., Rojo, J.S., Rotaru, F., Salsac, M.D., Benitez, A.M. Sánchez, Sanchis, E., Şenyigit, M., De Séréville, N., Siciliano, M., Simpson, J., Sohler, D., Sorlin, O., Stanoiu, M., Stodel, C., Suzuki, D., Theisen, C., Thomas, J.C., Ujic, P., Valiente-Dobón, J.J., Zielińska, M., Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Pluridisciplinaire Hubert Curien (IPHC), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear Theory (nucl-th), Nuclear Theory, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], FOS: Physical sciences, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract: The structure of the unbound $^{15}$F nucleus is investigated using the inverse kinematics resonant scattering of a radioactive $^{14}$O beam impinging on a CH$_2$ target. The analysis of $^{1}$H($^{14}$O,p)$^{14}$O and $^{1}$H($^{14}$O,2p)$^{13}$N reactions allowed the confirmation of the previously observed narrow $1/2^{-}$ resonance, near the two-proton decay threshold, and the identification of two new narrow 5/2$^{-}$ and 3/2$^{-}$ resonances. The newly observed levels decay by 1p emission to the ground of $^{14}$O, and by sequential 2p emission to the ground state (g.s.) of $^{13}$N via the $1^-$ resonance of $^{14}$O. Gamow shell model (GSM) analysis of the experimental data suggests that the wave functions of the 5/2$^{-}$ and 3/2$^{-}$ resonances may be collectivized by the continuum coupling to nearby 2p- and 1p- decay channels. The observed excitation function $^{1}$H($^{14}$O,p)$^{14}$O and resonance spectrum in $^{15}$F are well reproduced in the unified framework of the GSM., Comment: 7 pages, 4 figures
Published: 2021

10. Complete set of bound negative-parity states in the neutron-rich nucleus

Author: Ziliani S., Ciemala M., Crespi F. C. L., Leoni S., Fornal B., Suzuki T., Otsuka T., Maj A., Bednarczyk P., Benzoni G., Bracco A., Boiano C., Bottoni S., Brambilla S., Bast M., Beckers M., Braunroth T., Camera F., Cieplicka-Orynczak N., Clement E., Coelli S., Dorvaux O., Erturk S., de France G., Fransen C., Goldkuhle A., Grebosz J., Harakeh M. N., Iskra L. W., Jacquot B., Karpov A., Kicinska-Habior M., Kim Y., Kmiecik M., Lemasson A., Lenzi S. M., Lewitowicz M., Li H., Matea I., Mazurek K., Michelagnoli C., Matejska-Minda M., Million B., Muller-Gatermann C., Nanal V., Napiorkowski P., Napoli D. R., Palit R., Rejmund M., Schmitt CH., Stanoiu M., Stefan I., Vardaci E., Wasilewska B., Wieland O., Zieblinski M., Zielinska M., Ziliani, S., Ciemala, M., Crespi, F. C. L., Leoni, S., Fornal, B., Suzuki, T., Otsuka, T., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Orynczak, N., Clement, E., Coelli, S., Dorvaux, O., Erturk, S., de France, G., Fransen, C., Goldkuhle, A., Grebosz, J., Harakeh, M. N., Iskra, L. W., Jacquot, B., Karpov, A., Kicinska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Lenzi, S. M., Lewitowicz, M., Li, H., Matea, I., Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., Muller-Gatermann, C., Nanal, V., Napiorkowski, P., Napoli, D. R., Palit, R., Rejmund, M., Schmitt, Ch., Stanoiu, M., Stefan, I., Vardaci, E., Wasilewska, B., Wieland, O., Zieblinski, M., and Zielinska, M.
Abstract: High-resolution -ray spectroscopy of is performed with the Advanced GAmma Tracking Array, following deep-inelastic processes induced by an beam on a target. Six states are newly identified, which together with the three known excitations exhaust all negative-parity excited states expected in below the neutron threshold. Spin and parities are proposed for all located states on the basis of decay branchings and comparison with large-scale shell-model calculations performed in the p-sd space, with the YSOX interaction. Of particular interest is the location of the and excitations, which provide strong constrains for cross-shell p-sd matrix elements based on realistic interactions and help to simultaneously reproduce the ground and first-excited states in and , for the first time. Understanding the structure may also have significant impact on neutron-capture cross-section calculations in r-process modeling including light neutron-rich nuclei.
Published: 2021

11. First beta-decay spectroscopy of In-135 and new beta-decay branches of In-134

Author: Piersa-Silkowska, M, Korgul, A, Benito, J, Fraile, LM, Adamska, E, Andreyev, AN, Alvarez-Rodriguez, R, Barzakh, AE, Benzoni, G, Berry, T, Borge, MJG, Carmona, M, Chrysalidis, K, Correia, JG, Costache, C, Cubiss, JG, Goodacre, T Day, De Witte, H, Fedorov, D, Fedosseev, VN, Fernandez-Martinez, G, Fijalkowska, A, Fynbo, H, Galaviz, D, Galve, P, Garcia-Diez, M, Greenlees, PT, Grzywacz, R, Harkness-Brennan, LJ, Henrich, C, Huyse, M, Ibanez, P, Illana, A, Janas, Z, Johnston, K, Jolie, J, Judson, DS, Karanyonchev, V, Kicinska-Habior, M, Konki, J, Koszuk, L, Kurcewicz, J, Lazarus, I, Lica, R, Lopez-Montes, A, Mach, H, Madurga, M, Marroquin, I, Marsh, B, Martinez, MC, Mazzocchi, C, Miernik, K, Mihai, C, Marginean, N, Marginean, R, Negret, A, Nacher, E, Ojala, J, Olaizola, B, Page, RD, Pakarinen, J, Pascu, S, Paulauskas, S, Perea, A, Pucknell, V, Rahkila, P, Raison, C, Rapisarda, E, Rezynkina, K, Rotaru, F, Rothe, S, Rykaczewski, KP, Regis, J-M, Schomacker, K, Silkowski, M, Simpson, G, Sotty, C, Stan, L, Stanoiu, M, Stryjczyk, M, Sanchez-Parcerisa, D, Sanchez-Tembleque, V, Tengblad, O, Turturica, A, Udias, JM, Van Duppen, P, Vedia, V, Villa, A, Vinals, S, Wadsworth, R, Walters, WB, Warr, N, and Wilkins, SG
Subjects: ISOMER, Science & Technology, NEUTRON EMISSION PROBABILITIES, Physics, MODEL, Physics, Nuclear, NUCLEAR-DATA SHEETS, STATES, Physical Sciences, ISOTOPES, PICOSECOND LIFETIME MEASUREMENTS, RICH NUCLEI, HALF-LIVES, SN-132
Abstract: ispartof: PHYSICAL REVIEW C vol:104 issue:4 status: published
Published: 2021

12. First beta-decay spectroscopy of In-135 and new beta-decay branches of In-134

Author: Piersa-Silkowska, M, Korgul, A, Benito, J, Fraile, LM, Adamska, E, Andreyev, AN, Alvarez-Rodriguez, R, Barzakh, AE, Benzoni, G, Berry, T, Borge, MJG, Carmona, M, Chrysalidis, K, Correia, JG, Costache, C, Cubiss, JG, Goodacre, T Day, De Witte, H, Fedorov, DV, Fedosseev, VN, Fernandez-Martinez, G, Fijalkowska, A, Fynbo, H, Galaviz, D, Galve, P, Garcia-Diez, M, Greenlees, PT, Grzywacz, R, Harkness-Brennan, LJ, Henrich, C, Huyse, M, Ibanez, P, Illana, A, Janas, Z, Johnston, K, Jolie, J, Judson, DS, Karanyonchev, V, Kicinska-Habior, M, Konki, J, Koszuk, L, Kurcewicz, J, Lazarus, I, Lica, R, Lopez-Montes, A, Mach, H, Madurga, M, Marroquin, I, Marsh, B, Martinez, MC, Mazzocchi, C, Miernik, K, Mihai, C, Marginean, N, Marginean, R, Negret, A, Nacher, E, Ojala, J, Olaizola, B, Page, RD, Pakarinen, J, Pascu, S, Paulauskas, SV, Perea, A, Pucknell, V, Rahkila, P, Raison, C, Rapisarda, E, Rezynkina, K, Rotaru, F, Rothe, S, Rykaczewski, KP, Regis, J-M, Schomacker, K, Silkowski, M, Simpson, G, Sotty, C, Stan, L, Stanoiu, M, Stryjczyk, M, Sanchez-Parcerisa, D, Sanchez-Tembleque, V, Tengblad, O, Turturica, A, Udias, JM, Van Duppen, P, Vedia, V, Villa, A, Vinals, S, Wadsworth, R, Walters, WB, Warr, N, Wilkins, SG, and Collaboration, IDS
Published: 2021

13. Measurement of $^{238}\mathrm{U}(n,{n}^{{'}}{\gamma}$) cross section data and their impact on reaction models

Author: Kerveno, M., Dupuis, M., Bacquias, A., Belloni, F., Bernard, D., Borcea, C., Boromiza, M., Capote, R., De Saint Jean, C., Dessagne, P., Drohé, J., Henning, G., Hilaire, S., Kawano, T., Leconte, P., Nankov, N., Negret, A., Nyman, M., Olacel, A., Plompen, A., Romain, P., Rouki, C., Rudolf, G., Stanoiu, M., Wynants, R., Département Recherches Subatomiques (DRS-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Détection et de Géophysique (CEA) (LDG), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Commission - Joint Research Centre [Geel] (JRC), Horia Hulubei National Institute for Physics and Nuclear Engineering, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Matière sous Conditions Extrêmes (LMCE), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Etudes de PHysique (LEPH), Service de Physique des Réacteurs et du Cycle (SPRC), Département Etude des Réacteurs (DER), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Département Etude des Réacteurs (DER), International Atomic Energy Agency [Vienna] (IAEA), Los Alamos National Laboratory (LANL), European Project: 34186,EFNUDAT, European Project: 211499,EC:FP7:Fission,FP7-Fission-2007,EUFRAT(2008), European Project: 249671,EC:FP7:Fission,FP7-Fission-2009,ANDES(2010), European Project: 605203,EC:FP7:Fission,FP7-Fission-2013,CHANDA(2013), European Project: 847552,SANDA, and European Project: 516487,NUDAME
Subjects: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract: International audience; A better knowledge of ($n,xn$) reaction cross sections is important for both reaction modeling and energy applications. This article focuses on inelastic scattering of neutrons off $^{238}$U for which improvements are needed to better constrain evaluations and solve inconsistencies in nuclear power reactor calculations. A new precise measurement of ($n,xn\gamma$) reaction cross sections on $^{238}$U has been performed at the GELINA (Geel Electron LINear Accelerator) neutron facility operated by EC-JRC-Geel (Belgium) with the GRAPhEME (GeRmanium array for Actinides PrEcise MEasurements) setup. The prompt $\gamma$-ray spectroscopy method coupled to time-of-flight measurements is used to extract ($n,xn\gamma$) cross section values which can be further combined to infer the total neutron inelastic scattering cross section. Cross section data for 18 $\gamma$ transitions (five never measured before) are presented and compared to the data in the literature. Emphasis is especially given to the uncertainty determination to produce partial cross section data as accurate as possible. Due to intrinsic limitations of the experimental method, the use of additional nuclear structure information coupled with theoretical modeling is required to determine the total ($n,n′$) cross section over the whole neutron energy range. We have investigated modeling aspects of the $^{238}$U($n,n$'$\gamma$) cross sections related to the description of compound nucleus and preequilibirum mechanisms as well as the discrete part of nuclear structure. Through comparison between experimental and calculated ($n,n$'$\gamma$) cross sections, we pinpoint inaccuracies in the description of specific reaction mechanisms and challenge recently implemented models. This helps improving the whole modeling of the ($n,n′$) reaction.
Published: 2021

14. Lifetime analysis of short-lived states in $^{17}$N

Author: Ziliani, S., Ciemała, M., Crespi, F. C.L., Leoni, S., Fornal, B., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Oryńczak, N., Clément, E., Coelli, S., Dorvaux, O., Erturk, S., De France, G., Fransen, C., Goldkuhle, A., Grȩbosz, J., Harakeh, M. N., Iskra, W., Jacquot, B., Karpov, A., Kicińska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Lenzi, S. M., Lewitowicz, M., Li, H., Matea, I., Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., Müller-Gatermann, C., Nanal, V., Napiorkowski, P., Napoli, D. R., Palit, R., Rejmund, M., Schmitt, C., Stanoiu, M., Stefan, I., Vardaci, E., Wasilewska, B., Wieland, O., Ziȩbliński, M., Zielińska, M., Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Laue-Langevin (ILL), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Ziliani, S., Ciemala, M., Crespi, F. C. L., Leoni, S., Fornal, B., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Orynczak, N., Clement, E., Coelli, S., Dorvaux, O., Erturk, S., De France, G., Fransen, C., Goldkuhle, A., Grebosz, J., Harakeh, M. N., Iskra, L. W., Jacquot, B., Karpov, A., Kicinska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Lenzi, S. M., Lewitowicz, M., Li, H., Matea, I., Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., Muller-Gatermann, C., Nanal, V., Napiorkowski, P., Napoli, D. R., Palit, R., Rejmund, M., Schmitt, C., Stanoiu, M., Stefan, I., Vardaci, E., Wasilewska, B., Wieland, O., Zieblinski, M., Zielinska, M., and Research unit Nuclear & Hadron Physics
Subjects: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Abstract: International audience; A recent extension of the Doppler-shift attenuation method to measure short lifetimes of states populated in low-energy binary reactions is applied to the case of 17N. The reliability of the technique is confirmed by measuring the lifetime of the 5515 keV 3/2− state, which is depopulated by two different γ rays. The method is used to measure the lifetime of the 5170 keV (9/2+) state in the same nucleus. Comparisons with large-scale shell-model predictions are given as well.
Published: 2020

15. Testing ab initio nuclear structure in neutron-rich nuclei: Lifetime measurements of second 2+ state in C 16 and O 20

Author: Ciemala, M., Ziliani, S., Crespi, F. C. L., Leoni, S., Fornal, B., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Orynczak, N., Clement, E., Coelli, S., Dorvaux, O., Erturk, S., De France, G., Fransen, C., Goldkuhle, A., Grebosz, J., Harakeh, M. N., Iskra, L. W., Jacquot, B., Karpov, A., Kicinska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Lenzi, S. M., Lewitowicz, M., Li, H., Matea, I., Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., Muller-Gatermann, C., Nanal, V., Napiorkowski, P., Napoli, D. R., Palit, R., Rejmund, M., Schmitt, C., Stanoiu, M., Stefan, I., Vardaci, E., Wasilewska, B., Wieland, O., Zieblinski, M., Zielinska, M., Atac, A., Barrientos, D., Birkenbach, B., Boston, A. J., Cederwall, B., Charles, L., Collado, J., Cullen, D. M., Desesquelles, P., Domingo-Pardo, C., Dudouet, J., Eberth, J., Gonzalez, V., Goupil, J., Harkness-Brennan, L. J., Hess, H., Judson, D. S., Jungclaus, A., Korten, W., Labiche, M., Lefevre, A., Menegazzo, R., Mengoni, D., Nyberg, J., Perez-Vidal, R. M., Podolyak, Z., Pullia, A., Recchia, F., Reiter, P., Saillant, F., Salsac, M. D., Sanchis, E., Stezowski, O., Theisen, C., Valiente-Dobon, J. J., Holt, J. D., Menendez, J., Schwenk, A., Simonis, J., Ciemala, M., Ziliani, S., Crespi, F. C. L., Leoni, S., Fornal, B., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Orynczak, N., Clement, E., Coelli, S., Dorvaux, O., Erturk, S., De France, G., Fransen, C., Goldkuhle, A., Grebosz, J., Harakeh, M. N., Iskra, L. W., Jacquot, B., Karpov, A., Kicinska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Lenzi, S. M., Lewitowicz, M., Li, H., Matea, I., Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., Muller-Gatermann, C., Nanal, V., Napiorkowski, P., Napoli, D. R., Palit, R., Rejmund, M., Schmitt, C., Stanoiu, M., Stefan, I., Vardaci, E., Wasilewska, B., Wieland, O., Zieblinski, M., Zielinska, M., Atac, A., Barrientos, D., Birkenbach, B., Boston, A. J., Cederwall, B., Charles, L., Collado, J., Cullen, D. M., Desesquelles, P., Domingo-Pardo, C., Dudouet, J., Eberth, J., Gonzalez, V., Goupil, J., Harkness-Brennan, L. J., Hess, H., Judson, D. S., Jungclaus, A., Korten, W., Labiche, M., Lefevre, A., Menegazzo, R., Mengoni, D., Nyberg, J., Perez-Vidal, R. M., Podolyak, Z., Pullia, A., Recchia, F., Reiter, P., Saillant, F., Salsac, M. D., Sanchis, E., Stezowski, O., Theisen, C., Valiente-Dobon, J. J., Holt, J. D., Menendez, J., Schwenk, A., and Simonis, J.
Abstract: To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2+ state in neutron-rich O20,τ(22+)=150-30+80fs, and an estimate for the lifetime of the second 2+ state in C16 have been obtained for the first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure nuclear state lifetimes in the tens-to-hundreds of femtoseconds range by analyzing the Doppler-shifted γ-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction O18(7.0MeV/u)+Ta181. The requested sensitivity could only be reached owing to the excellent performances of the Advanced γ-Tracking Array AGATA, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The experimental lifetimes agree with predictions of ab initio calculations using two-and three-nucleon interactions, obtained with the valence-space in-medium similarity renormalization group for O20 and with the no-core shell model for C16. The present measurement shows the power of electromagnetic observables, determined with high-precision γ spectroscopy, to assess the quality of first-principles nuclear structure calculations, complementing common benchmarks based on nuclear energies. The proposed experimental approach will be essential for short lifetime measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense beams, produced by Isotope Separation On-Line (ISOL) techniques, become available.
Published: 2020

16. Probing nuclear forces beyond the nuclear drip line: The cases of $^{16}$F and $^{15}$F

Author: Girard-Alcindor, V., Stefan, I., Santos, F. de Oliveira, Sorlin, O., Ackermann, D., Adsley, P., Angelique, J. C., Assie, M., Assuncao, M., Beaumel, D., Berthoumieux, E., Borcea, R., Caceres, L., Celikovic, I., Ciemala, M., Chudoba, V., Agata, G. D, de Grancey, F., Dumitru, G., Flavigny, F., Fougeres, C., Franchoo, S., Georgiadou, A., Grevy, S., Guillot, J., Guimaraes, V., Hammache, F., Kamalou, O., Kiener, J., Koyama, S., Lalanne, L., Lapoux, V., Matea, I., Matta, A., Meyer, A., Morfouace, P., Mrazek, J., Negoita, F., Niikura, M., Pantelica, D., Perrot, L., Petrone, C., Piot, J., Portail, C., Roger, T., Rotaru, F., Benitez, A. M. Sanchez, de Sereville, N., Stanoiu, M., Stodel, C., Subotic, K., Suzuki, D., Tatischeff, V., Thomas, J. C., Ujic, P., and Verney, D.
Subjects: Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: The unbound proton-rich nuclei $^{16}$F and $^{15}$F are investigated experimentally and theoretically. Several experiments using the resonant elastic scattering method were performed at GANIL with radioactive beams to determine the properties of the low lying states of these nuclei. Strong asymmetry between $^{16}$F-$^{16}$N and $^{15}$F-$^{15}$C mirror nuclei is observed. The strength of the $nucleon-nucleon$ effective interaction involving the loosely bound proton in the $s_{1/2}$ orbit is significantly modified with respect to their mirror nuclei $^{16}$N and $^{15}$C. The reduction of the effective interaction is estimated by calculating the interaction energies with a schematic zero-range force. It is found that, after correcting for the effects due to changes in the radial distribution of the single-particle wave functions, the mirror symmetry of the $n-p$ interaction is preserved between $^{16}$F and $^{16}$N, while a difference of 63\% is measured between the $p-p$ versus $n-n$ interactions in the second excited state of $^{15}$F and $^{15}$C nuclei. Several explanations are proposed.
Published: 2021

17. Complete set of bound negative-parity states in the neutron-rich $^{18}$N nucleus

Author: Ziliani, S., Ciema��a, M., Crespi, F. C. L., Leoni, S., Fornal, B., Suzuki, T., Otsuka, T., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Orynczak, N., Cl��ment, E., Coelli, S., Dorvaux, O., Erturk, S., De France, G., Fransen, C., Goldkuhle, A., Grebosz, J., Harakeh, M. N., Iskra, ��. W., Jacquot, B., Karpov, A., Kicinska-Habior, M., Kimi, Y. -H., Kmiecik, M., Lemasson, A., Lewitowicz, M., Lenzi, S., Li, H., Matea, I., Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., M��ller-Gatermann, C., Nanal, V., Napiorkowski, P., Napoli, D. R., Palit, R., Rejmund, M., Schmitt, Ch., Stanoiu, M., Stefan, I., Vardaci, E., Wasilewska, B., Wieland, O., Zieblinski, M., Zielinska, M., Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut Laue-Langevin (ILL), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract: International audience; High-resolution γ-ray spectroscopy of N18 is performed with the Advanced GAmma Tracking Array, following deep-inelastic processes induced by an O18 beam on a Ta181 target. Six states are newly identified, which together with the three known excitations exhaust all negative-parity excited states expected in N18 below the neutron threshold. Spin and parities are proposed for all located states on the basis of decay branchings and comparison with large-scale shell-model calculations performed in the p-sd space, with the YSOX interaction. Of particular interest is the location of the 01− and 12− excitations, which provide strong constrains for cross-shell p-sd matrix elements based on realistic interactions and help to simultaneously reproduce the ground and first-excited states in N16 and N18, for the first time. Understanding the N18 structure may also have significant impact on neutron-capture cross-section calculations in r-process modeling including light neutron-rich nuclei.
Published: 2021

18. Probing nuclear forces beyond the nuclear drip line: the cases of 16F and 15F: a tribute to Mahir Hussein

Author: Girard-Alcindor, V, Stefan, I, de Oliveira Santos, F, Sorlin, O, Ackermann, D, Adsley, P, Angélique, J C, Assié, M, Assunção, M, Beaumel, D, Berthoumieux, E, Borcea, R, Cáceres, L, Čeliković, Igor T., Ciemala, M, Chudoba, V, D’Agata, G, de Grancey, F, Dumitru, G, Flavigny, F, Fougères, C, Franchoo, S, Georgiadou, A, Goyal, N, Grévy, S, Guillot, J, Guimaraes, V, Hammache, F, Kamalou, O, Kiener, J, Koyama, S, Lalanne, L, Lapoux, V, Matea, I, Matta, A, Meyer, A, Michel, N, Morfouace, P, Mrazek, J, Negoita, F, Niikura, M, Pantelica, D, Perrot, L, Petrone, C, Piot, J, Portail, C, Roger, T, Rotaru, F, Sánchez Benítez, A M, de Séréville, N, Stanoiu, M, Stodel, C, Subotić, Krunoslav M., Suzuki, D, Tatischeff, V, Thomas, J C, Ujić, Predrag, and Verney, D
Subjects: Nuclear Theory, Nuclear Experiment
Abstract: The unbound proton-rich nuclei 16F and 15F are investigated experimentally and theoretically. Several experiments using the resonant elastic scattering method were performed at GANIL with radioactive beams to determine the properties of the low lying states of these nuclei. Strong asymmetry between 16F–16N and 15F–15C mirror nuclei is observed. The strength of the nucleon- nucleon effective interaction involving the loosely bound proton in the s1 / 2 orbit is significantly modified with respect to their mirror nuclei 16N and 15C. The reduction of the effective interaction is estimated by calculating the interaction energies with a schematic zero-range force. It is found that, after correcting for the effects due to changes in the radial distribution of the single-particle wave functions, the mirror symmetry of the n- p interaction is preserved between 16F and 16N, while a difference of 63% is measured between the p- p versus n- n interactions in the second excited state of 15F and 15C nuclei. Several explanations are proposed. © 2021, The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature. Part of a collection: Cluster Structure and Dynamics of Nuclei - A Tribute to Mahir Hussein. [] Preprint version available at: [https://arxiv.org/abs/2101.02132]
Published: 2021

19. Coulomb and nuclear excitations of $^{70}$Zn and $^{68}$Ni at intermediate energy

Author: Calinescu, S., Sorlin, O., Matea, I., Carstoiu, F., Dao, D., Nowacki, F., de Angelis, G., Astabatyan, R., Bagchi, S., Borcea, C., Borcea, R., C��ceres, L., Ciem��la, M., Cl��ment, E., Dombr��di, Z., Franchoo, S., Gottardo, A., Gr��vy, S., Guerin, H., Harakeh, M. N., Harca, I. M., Kamalou, O., Kmiecik, M., Krasznahorkay, A., Krzysiek, M., Kuti, I., Lepailleur, A., Lukyanov, S., Maj, A., Maslov, V., Mazurek, K., Morfouace, P., Mrazek, J., Negoita, F., Niikura, M., Olivier, L., Penionzhkevich, Y., Perrot, L., Petrone, C., Podoly��k, Z., Rigollet, C, Roger, T., Rotaru, F., Sohler, D., Stanoiu, M., Stefan, I., Stuhl, L., Thomas, J. C., Vajta, Z., Vandebrouck, M., Wieland, O., Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear Theory (nucl-th), Nuclear Theory, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], FOS: Physical sciences, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract: International audience; The reduced transition probabilities $B(E2; 0^+_{g.s.}\rightarrow2_1^+,2^+_2)$ in $^{70}$Zn and the full $B(E2; 0^+_{g.s.}\rightarrow2^+)$ strength up to S$_n$=7.79 MeV in $^{68}$Ni have been determined at the LISE/GANIL facility using the Coulomb-excitation technique at intermediate beam energy on a $^{208}$Pb target. The $\gamma$ rays emitted in-flight were detected with an array of 46 BaF$_2$ crystals. The angles of the deflected nuclei were determined in order to disentangle and extract the Coulomb and nuclear contributions to the excitation of the 2$^+$ states. The measured $B(E2; 0^+_{g.s.}\rightarrow2_1^+)$ of 1432(124) e$^2$fm$^4$ for $^{70}$Zn falls in the lower part of the published values which clustered either around 1600 or above 2000 e$^2$fm$^4$, while the $B(E2; 0^+_{g.s.}\rightarrow2^+_2)$ of 53(7) e$^2$fm$^4$ agrees very well with the two published values. The relatively low $B(E2; 0^+_{g.s.}\rightarrow2_1^+)$ of 301(38) e$^2$fm$^4$ for $^{68}$Ni agrees with previous studies and confirms a local magicity at $Z=28, N=40$. Combining the results of the low-energy spectra of $^{68}$Ni and $^{70}$Zn and their shell-model interpretations, it is interesting to notice that four different shapes (spherical, oblate, prolate and triaxial) are present. Finally, a summed $E2$ strength of only about 150 e$^2$fm$^4$ has been found experimentally at high excitation energy, likely due to proton excitations across the $Z=28$ gap. The experimental distribution of this high-energy $E2$ excitation agrees with SM calculations, but its strength is about two times weaker.
Published: 2021

20. Low-lying single-particle structure of C and the = 14 Sub-shell Closure

Author: Pereira-López, X., Fernández-Domínguez, B., Delaunay, F., Achouri, N.L., Orr, N.A., Catford, W.N., Assié, M., Bailey, S., Bastin, B., Blumenfeld, Y., Borcea, R., Caamaño, M., Caceres, L., Clément, E., Corsi, A., Curtis, N., Deshayes, Q., Farget, F., Fisichella, M., de France, G., Franchoo, S., Freer, M., Gibelin, J., Gillibert, A., Grinyer, G.F., Hammache, F., Kamalou, O., Knapton, A., Kokalova, T., Lapoux, V., Lay, J.A., Le Crom, B., Leblond, S., Lois-Fuentes, J., Marqués, F.M., Matta, A., Morfouace, P., Moro, A.M., Otsuka, T., Pancin, J., Perrot, L., Piot, J., Pollacco, E., Ramos, D., Rodríguez-Tajes, C., Roger, T., Rotaru, F., Sénoville, M., de Séréville, N., Smith, R., Sorlin, O., Stanoiu, M., Stefan, I., Stodel, C., Suzuki, D., Suzuki, T., Thomas, J.C., Timofeyuk, N., Vandebrouck, M., Walshe, J., and Wheldon, C.
Abstract: The first investigation of the single-particle structure of the bound states of $^{17}$C, via the d(16C,p) transfer reaction, has been undertaken. The measured angular distributions confirm the spin-parity assignments of 1/2+ and 5/2+ for the excited states located at 217 and 335 keV, respectively. The spectroscopic factors deduced for these states exhibit a marked single-particle character, in agreement with shell model and particle-core model calculations, and combined with their near degeneracy in energy provide clear evidence for the absence of the N=14 sub-shell closure. The very small spectroscopic factor found for the 3/2+ ground state is consistent with theoretical predictions and indicates that the ν1d3/2 strength is carried by unbound states. With a dominant ℓ=0 valence neutron configuration and a very low separation energy, the 1/2+ excited state is a one-neutron halo candidate.
Published: 2020

21. DETERMINATION OF LIFETIMES OF EXCITED STATES IN NEUTRON-RICH O-20 ISOTOPE FROM EXPERIMENT WITH THE AGATA plus PARIS plus VAMOS SETUP

Author: Ciemala, M., Ziliani, S., Crespi, F., Leoni, S., Fornal, B., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Orynczak, N., Clement, E., Dorvaux, O., Erturk, S., De France, G., Goldkuhle, A., Grebosz, J., Harakeh, M. N., Iskra, L. W., Jacquot, B., Karpov, A., Kicinska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Li, H., Matea, I, Mazurek, K., Michelagnoli, C., Millon, B., Mueller-Gatermann, C., Napiorkowski, P., Nanal, V, Matejska-Minda, M., Rejmund, M., Sowicki, B., Schmitt, Ch, Stanoiu, M., Stefan, I, Wasilewska, B., Zielinska, M., Zieblinski, M., Fornal, Bogdan -- 0000-0002-1142-8067, Ciemala, Michal -- 0000-0001-5328-720X, and [Ciemala, M. -- Fornal, B. -- Maj, A. -- Bednarczyk, P. -- Cieplicka-Orynczak, N. -- Grebosz, J. -- Iskra, L. W. -- Kmiecik, M. -- Mazurek, K. -- Sowicki, B. -- Wasilewska, B. -- Zieblinski, M.] Polish Acad Sci, Inst Nucl Phys, PL-31342 Krakow, Poland -- [Ziliani, S. -- Crespi, F. -- Leoni, S. -- Bracco, A. -- Bottoni, S. -- Brambilla, S. -- Camera, F.] Univ Milan, Via Celoria 16, I-20133 Milan, Italy -- [Ziliani, S. -- Crespi, F. -- Leoni, S. -- Benzoni, G. -- Bracco, A. -- Boiano, C. -- Bottoni, S. -- Camera, F. -- Millon, B.] INFN, Sez Milano, Milan, Italy -- [Bast, M. -- Beckers, M. -- Braunroth, T. -- Goldkuhle, A. -- Mueller-Gatermann, C.] IKP Cologne, Cologne, Germany -- [Clement, E. -- De France, G. -- Jacquot, B. -- Kim, Y. -- Lemasson, A. -- Li, H. -- Rejmund, M.] CEA DSAM, GANIL, Caen 05, France -- [Clement, E. -- De France, G. -- Jacquot, B. -- Kim, Y. -- Lemasson, A. -- Li, H. -- Rejmund, M.] CNRS, IN2P3, Caen 05, France -- [Dorvaux, O. -- Schmitt, Ch] CNRS, IN2P3, IPHC UMR 7178, F-67037 Strasbourg, France -- [Erturk, S.] Nigde Univ, Nigde, Turkey -- [Harakeh, M. N.] KVI Ctr Adv Radiat Technol, Groningen, Netherlands -- [Karpov, A.] JINR, Dubna, Russia -- [Kicinska-Habior, M.] Warsaw Univ, Fac Phys, Warsaw, Poland -- [Matea, I -- Stefan, I] IPN Orsay Lab, Orsay, France -- [Michelagnoli, C.] ILL Grenoble, Grenoble, France -- [Napiorkowski, P. -- Matejska-Minda, M.] Univ Warsaw, Heavy Ion Lab, Pasteura 5A, PL-02093 Warsaw, Poland -- [Nanal, V] Tata Inst Fundamental Res, Dept Nucl & Atom Phys, Mumbai 400005, Maharashtra, India -- [Stanoiu, M.] IFIN HH, Bucharest, Romania -- [Zielinska, M.] Ctr CEA Saclay, IRFU, CEA DRF, F-91191 Gif Sur Yvette, France
Abstract: Zakopane Conference on Nuclear Physics - Extremes of the Nuclear Landscape -- AUG 26-SEP 02, 2018 -- Zakopane, POLAND, WOS: 000463866500051, An experiment aiming at measuring lifetimes of the second 2(+) excited states in neutron-rich C and O isotopes was recently performed at the GANIL laboratory, in France. In these nuclei, recent ab initio calculations provide a detailed description of the nuclear excited states, predicting a strong sensitivity of the electromagnetic transition probabilities to the details of the nucleon-nucleon interactions, especially in connection with the role played by the three-body (NNN) forces. Thus, the measurement of 2(+) states lifetimes in this region will be a stringent test of the importance of including the NNN forces in describing the electromagnetic properties of selected nuclear states. This contribution reports on the status of the experimental analysis for the case of lifetimes in O-20., European Union's Horizon 2020 through ENSAR2 grant [654002]; National Science Centre, Poland (NCN) [2013/08/M/ST2/00257, 2014/14/M/ST2/00738, 2016/22/M/ST2/00269]; COPININ2P3 collaboration, We acknowledge the important technical contributions of J. Goupil and the GANIL accelerator staff. The authors acknowledge support from the European Union's Horizon 2020 through ENSAR2 grant agreement No. 654002, the National Science Centre, Poland (NCN) Contract No. 2013/08/M/ST2/00257, 2014/14/M/ST2/00738 and 2016/22/M/ST2/00269 and COPININ2P3 collaboration.
Published: 2019

22. Evaluation of the 13N(α,p)16O thermonuclear reaction rate and its impact on the isotopic composition of supernova grains

Author: Meyer, A., De Séréville, Nicolas, Laird, Alison Monica, Fox, Simon Paul, Riley, Joscelin, Williams, Matthew, Hammache, F., Longland, R., Lawson, Tracy, Pignatari, M., Audouin, L., Beaumel, D., Fortier, S., Kiener, J., Lefebvre-Schuhl, A., Pellegriti, M. G., Stanoiu, M, and Tatischeff, V
Published: 2020

23. The Structure of ³³Si and the magicity of the N=20 gap at Z=14

Author: Jongile, S., Lemasson, A., Sorlin, O., Wiedeking, M., Papka, P., Bazin, D., Borcea, C., Borcea, R., Gade, A., Iwasaki, H., Khan, E., Lepailleur, A., Mutschler, A., Nowacki, F., Recchia, F., Roger, T., Rotaru, F., Stanoiu, M., Stroberg, S.R, Tostevin, J.A, Vanderbrouck, M., Weisshaar, D., and Wimmer, K.
Abstract: The structure of ³³Si was studied by a one-neutron knockout reaction from a ³⁴Si beam at 98.5 MeV/u incident on a 9 Be target. The prompt γ rays following the de-excitation of ³³Si were detected using the GRETINA γ -ray tracking array while the reaction residues were identified on an event-by-event basis in the focal plane of the S800 spectrometer at the National Superconducting Cyclotron Laboratory. The presently derived spectroscopic factor values, C 2 S , for the 3 / 2 + and 1 / 2 + states, corresponding to a neutron removal from the 0 d 3 / 2 and 1 s 1 / 2 orbitals, agree with shell model calculations and point to a strong N = 20 shell closure. Three states arising from the more bound 0 d 5 / 2 orbital are proposed, one of which is unbound by about 930 keV. The sensitivity of this experiment has also confirmed a weak population of 9 / 2 − and 11 / 2 − 1 , 2 final states, which originate from a higher-order process. This mechanism may also have populated, to some fraction, the 3 / 2 − and 7 / 2 − negative-parity states, which hinders a determination of the C 2 S values for knockout from the normally unoccupied 1 p 3 / 2 and 0 f 7 / 2 orbits.
Published: 2020

24. Fast-timing study of Ga 81 from the β decay of Zn 81

Author: Paziy, V., Fraile, L.M., Mach, H., Olaizola, B., Simpson, G.S., Aprahamian, A., Bernards, C., Briz, José Antonio, Bucher, B., Chiara, C.J., Dlouhý, Z., Gheorghe, I., Ghita, D., Hoff, P., Jolie, J., Köster, U., Kurcewicz, W., Lică, R., Marginean, N., Marginean, R., Régis, J.M., Rudigier, M., Sava, T., Stanoiu, M., Stroe, L., Walters, W.B., Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Department of Energy (US), Federal Ministry of Education and Research (Germany), Universidad Complutense de Madrid, and European Commission
Abstract: 18 pags., 10 figs., 4 tabs., The β- decay of Zn81 to the neutron magic N=50 nucleus Ga81, with only three valence protons with respect to Ni78, was investigated. The study was performed at the ISOLDE facility at CERN by means of γ spectroscopy. The Zn81 half-life was determined to be T1/2=290(4) ms while the β-delayed neutron emission probability was measured as Pn=23(4)%. The analysis of the β-gated γ-ray singles and γ-γ coincidences from the decay of Zn81 provides 47 new levels and 70 new transitions in Ga81. The β-n decay of Zn81 was observed and a new decay scheme into the odd-odd Ga80 nucleus was established. The half-lives of the first and second excited states of Ga81 were measured via the fast-timing method using LaBr3(Ce) detectors. The level scheme and transition rates are compared to large-scale shell-model calculations. The low-lying structure of Ga81 is interpreted in terms of the coupling of the three valence protons outside the doubly magic Ni78 core., This work was supported by the Spanish MINECO through the FPA2015-65035-P and RTI2018-098868-B-I00 projects, by the U.S. DoE Grant No. DE-FG02-94ER40834, by the German BMBF Grant 05P19PKFNA, and Grupo de Física Nuclear (GFN) at UCM. The support by the European Union Seventh Framework through ENSAR (Contract No. 262010) and ISOLDE (CERN) Collaboration is acknowledged. V.P. acknowledges support by the Spanish FPI-BES-2011-045931 grant.
Published: 2020

25. Testing ab initio nuclear structure in neutron-rich nuclei: Lifetime measurements of second 2 + state in C 16 and O 20

Author: Ciemała, M., Ziliani, S., Crespi, F., Leoni, S., Fornal, B., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Oryńczak, N., Clément, E., Coelli, S., Dorvaux, O., Erturk, S., De France, G., Fransen, C., Goldkuhle, A., Grębosz, J., Harakeh, M., Iskra, Ł., Jacquot, B., Karpov, A., Kicińska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Lenzi, S., Lewitowicz, M., Li, H., Matea, I., Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., Müller-Gatermann, C., Nanal, V., Napiorkowski, P., Napoli, D., Palit, R., Rejmund, M., Schmitt, CH., Stanoiu, M., Stefan, I., Vardaci, E., Wasilewska, B., Wieland, O., Zieblinski, M., Zielińska, M., Ataç, A., Barrientos, D., Birkenbach, B., Boston, A., Cederwall, B., Charles, L., Collado, J., Cullen, D., Désesquelles, P., Domingo-Pardo, C., Dudouet, J., Eberth, J., González, V., Goupil, J., Harkness-Brennan, L., Hess, H., Judson, D., Jungclaus, A., Korten, W., Labiche, M., Lefevre, A., Menegazzo, R., Mengoni, D., Nyberg, J., Perez-Vidal, R., Podolyak, Zs., Pullia, A., Recchia, F., Reiter, P., Saillant, F., Salsac, M., Sanchis, E., Stezowski, O., Theisen, Ch., Valiente-Dobón, J., Holt, J., Menéndez, J., Schwenk, A., Simonis, J., Institut Pluridisciplinaire Hubert Curien (IPHC), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS]Physics [physics], [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2020

26. Testing ab initio nuclear structure in neutron-rich nuclei : Lifetime measurements of second 2(+) state in C-16 and O-20

Author: Ciemala, M., Ziliani, S., Crespi, F. C. L., Leoni, S., Fornal, B., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Orynczak, N., Clement, E., Coelli, S., Dorvaux, O., Erturk, S., de France, G., Fransen, C., Goldkuhle, A., Grebosz, J., Harakeh, M. N., Iskra, L. W., Jacquot, B., Karpov, A., Kicinska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Lenzi, S. M., Lewitowicz, M., Li, H., Matea, I, Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., Mueller-Gatermann, C., Nanal, V, Napiorkowski, P., Napoli, D. R., Palit, R., Rejmund, M., Schmitt, Ch, Stanoiu, M., Stefan, I, Vardaci, E., Wasilewska, B., Wieland, O., Zieblinski, M., Zielinska, M., Atac, A., Barrientos, D., Birkenbach, B., Boston, A. J., Cederwall, B., Charles, L., Collado, J., Cullen, D. M., Desesquelles, P., Domingo-Pardo, C., Dudouet, J., Eberth, J., Gonzalez, V, Goupil, J., Harkness-Brennan, L. J., Hess, H., Judson, D. S., Jungclaus, A., Korten, W., Labiche, M., Alexis, L., Menegazzo, R., Mengoni, D., Nyberg, Johan, Perez-Vidal, R. M., Podolyak, Zs, Pullia, A., Recchia, F., Reiter, P., Saillant, F., Salsac, M. D., Sanchis, E., Stezowski, O., Theisen, C., Valiente-Dobon, J. J., Holt, J. D., Menendez, J., Schwenk, A., and Simonis, J.
Subjects: Subatomär fysik, Subatomic Physics
Abstract: To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2(+) state in neutron-rich O-20, tau(2(2)(+)) = 150(-30)(+80) fs, and an estimate for the lifetime of the second 2(+) state in C-16 have been obtained for the first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure nuclear state lifetimes in the tens-to-hundreds of femtoseconds range by analyzing the Doppler-shifted gamma-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction O-18 (7.0 MeV/u) + Ta-181. The requested sensitivity could only be reached owing to the excellent performances of the Advanced gamma-Tracking Array AGATA, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The experimental lifetimes agree with predictions of ab initio calculations using two- and three-nucleon interactions, obtained with the valence-space in-medium similarity renormalization group for O-20 and with the no-core shell model for C-16. The present measurement shows the power of electromagnetic observables, determined with high-precision gamma spectroscopy, to assess the quality of first-principles nuclear structure calculations, complementing common benchmarks based on nuclear energies. The proposed experimental approach will be essential for short lifetime measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense beams, produced by Isotope Separation On-Line (ISOL) techniques, become available.
Published: 2020

27. Structure of Si 33 and the magicity of the N=20 gap at Z=14

Author: Jongile, S., Lemasson, A., Sorlin, O., Wiedeking, M., Papka, P., Bazin, D., Borcea, C., Borcea, R., Gade, A., Iwasaki, H., Khan, E., Lepailleur, A., Mutschler, A., Nowacki, F., Recchia, F., Roger, T., Rotaru, F., Stanoiu, M., Stroberg, S. R., Tostevin, J. A., Vandebrouck, M., Weisshaar, D., and Wimmer, K.
Published: 2020

28. Evaluation of the $^{13}$N($��$,p)$^{16}$O thermonuclear reaction rate and its impact on the isotopic composition of supernova grains

Author: Meyer, A., de S��r��ville, N., Laird, A. M., Hammache, F., Longland, R., Lawson, T., Pignatari, M., Audouin, L., Beaumel, D., Fortier, S., Kiener, J., Lefebvre-Schuhl, A., Pellegriti, M. G., Stanoiu, M., and Tatischeff, V.
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex), Solar and Stellar Astrophysics (astro-ph.SR)
Abstract: It has been suggested that hydrogen ingestion into the helium shell of massive stars could lead to high $^{13}$C and $^{15}$N excesses when the shock of a core-collapse supernova passes through its helium shell. This prediction questions the origin of extremely high $^{13}$C and $^{15}$N abundances observed in rare presolar SiC grains which is usually attributed to classical novae. In this context $^{13}$N($��$,p)$^{16}$O the reaction plays an important role since it is in competition with $^{13}$N $��^+$-decay to $^{13}$C. The $^{13}$N($��$,p)$^{16}$O reaction rate used in stellar evolution calculations comes from the CF88 compilation with very scarce information on the origin of this rate. The goal of this work is to provide a recommended $^{13}$N($��$,p)$^{16}$O reaction rate, based on available experimental data. Unbound nuclear states in the $^{17}$F compound nucleus were studied using the spectroscopic information of the analog states in $^{17}$O nucleus that were measured at the Alto facility using the $^{13}$C($^7$Li,t)$^{17}$O alpha-transfer reaction, and spectroscopic factors were derived using a DWBA analysis. This spectroscopic information was used to calculate a recommended $^{13}$N($��$,p)$^{16}$O reaction rate with meaningful uncertainty using a Monte Carlo approach. The present $^{13}$N($��$,p)$^{16}$O reaction rate is found to be within a factor of two of the previous evaluation, with a typical uncertainty of a factor 2-3. The source of this uncertainty comes from the three resonances at $E_r^{c.m.} = 221$, 741 and 959 keV. This new error estimation translates to an overall uncertainty in the $^{13}$C production of a factor of 50. The main source of uncertainty on the re-evaluated $^{13}$N($��$,p)$^{16}$O reaction rate currently comes from the uncertain alpha-width of relevant $^{17}$F states.
Published: 2020
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29. Detailed spectroscopy of doubly magic $^{132}$Sn

Author: Benito, J., Fraile, L. M., Korgul, A., Piersa, M., Adamska, E., Andreyev, A. N., Álvarez-Rodríguez, R., Barzakh, A. E., Benzoni, G., Berry, T., Borge, M. J. G., Carmona, M., Chrysalidis, K., Costache, C., Cubiss, J. G., Goodacre, T. Day, De Witte, H., Fedorov, D. V., Fedosseev, V. N., Fernández-Martínez, G., Fijałkowska, A., Fila, M., Fynbo, H., Galaviz, D., Galve, P., García-Díez, M., Greenlees, P. T., Grzywacz, R., Harkness-Brennan, L. J., Henrich, C., Huyse, M., Ibáñez, P., Illana, A., Janas, Z., Jolie, J., Judson, D. S., Karayonchev, V., Kicinska-Habior, M., Konki, J., Kurcewicz, J., Lazarus, I., Lica, R., López-Montes, A., Lund, M., Mach, H., Madurga, M., Marroquín, I., Marsh, B., Martínez, M. C., Mazzocchi, C., Marginean, N., Marginean, R., Miernik, K., Mihai, C., Mihai, R. E., Nácher, E., Negret, A., Olaizola, B., Page, R. D., Paulauskas, S. V., Pascu, S., Perea, A., Pucknell, V., Rahkila, P., Raison, C., Rapisarda, E., Régis, J. -M., Rezynkina, K., Rotaru, F., Rothe, S., Sánchez-Parcerisa, D., Sánchez-Tembleque, V., Schomacker, K., Simpson, G. S., Sotty, Ch., Stan, L., Stanoiu, M., Stryjczyk, M., Tengblad, O., Turturica, A., Udías, J. M., Van Duppen, P., Vedia, V., Villa-Abaunza, A., Viñals, S., Walters, W. B., Wadsworth, R., Warr, N., Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), and IDS
Subjects: Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Nuclear Physics - Experiment, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment (nucl-ex), nucl-ex, Nuclear Structure, Nuclear Experiment
Abstract: The structure of the doubly magic $^{132}_{50}$Sn$_{82}$ has been investigated at the ISOLDE facility at CERN, populated both by the $\beta^-$decay of $^{132}$In and $\beta^-$-delayed neutron emission of $^{133}$In. The level scheme of $^{132}$Sn is greatly expanded with the addition of 68 $\gamma$-transitions and 17 levels observed for the first time in the $\beta$ decay. The information on the excited structure is completed by new $\gamma$-transitions and states populated in the $\beta$-n decay of $^{133}$In. Improved delayed neutron emission probabilities are obtained both for $^{132}$In and $^{133}$In. Level lifetimes are measured via the Advanced Time-Delayed $\beta\gamma\gamma$(t) fast-timing method. An interpretation of the level structure is given based on the experimental findings and the particle-hole configurations arising from core excitations both from the \textit{N} = 82 and \textit{Z} = 50 shells, leading to positive and negative parity particle-hole multiplets. The experimental information provides new data to challenge the theoretical description of $^{132}$Sn., Comment: 19 pages, 11 figures. Accepted for publication in Phys. Rev. C
Published: 2020
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30. Testing $ab initio$ nuclear structure in neutron-rich nuclei: lifetime measurements of second 2$^+$ states in $^{16}$C and $^{20}$O

Author: Ciemala, M., Ziliani, S., Crespi, F.C.L., Leoni, S., Fornal, B., Maj, A., Bednarczyk, P., Benzoni, G., Bracco, A., Boiano, C., Bottoni, S., Brambilla, S., Bast, M., Beckers, M., Braunroth, T., Camera, F., Cieplicka-Orynczak, N., Clément, E., Coelli, S., Dorvaux, O., Erturk, S., de France, G., Fransen, C., Goldkuhle, A., Grebosz, J., Harakeh, M.N., Iskra, L.W., Jacquot, B., Karpov, A., Kicinska-Habior, M., Kim, Y., Kmiecik, M., Lemasson, A., Lenzi, S.M., Lewitowicz, M., Li, H., Matea, I., Mazurek, K., Michelagnoli, C., Matejska-Minda, M., Million, B., Muller-Gatermann, C., Nanal, V., Napiorkowski, P., Napoli, D.R., Palit, R., Rejmund, M., Schmitt, Ch., Stanoiu, M., Stefan, I., Vardaci, E., Wasilewska, B., Wieland, O., Zieblinski, M., Zielinska, M., Atac, A., Barrientos, D., Birkenbach, B., Boston, A.J., Cederwall, B., Charles, L., Collado, J., Cullen, D.M., Desesquelles, P., Domingo-Pardo, C., Dudouet, J., Eberth, J., Gonzalez, V., Goupil, J., Harkness-Brennan, L.J., Hess, H., Judson, D.S., Jungclaus, A., Korten, W., Labiche, M., Lefevre, A., Menegazzo, R., Mengoni, D., Nyberg, J., Perez-Vidal, R.M., Podolyak, Zs., Pullia, A., Recchia, F., Reiter, P., Saillant, F., Salsac, M.D., Sanchis, E., Stezowski, O., Theisen, Ch., Valiente-Dobon, J.J., Holt, J.D., Menendez, J., Schwenk, A., Simonis, J., Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut Laue-Langevin (ILL), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), ILL, Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Nuclear Theory (nucl-th), nucl-th, Nuclear Theory, Nuclear Physics - Theory, Starke Wechselwirkung und exotische Kerne – Abteilung Blaum, FOS: Physical sciences, Nuclear Physics - Experiment, ddc:530, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nucl-ex, Nuclear Structure, Nuclear Experiment
Abstract: To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2+ state in neutron-rich O20,τ(22+)=150−30+80fs, and an estimate for the lifetime of the second 2+ state in C16 have been obtained for the first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure nuclear state lifetimes in the tens-to-hundreds of femtoseconds range by analyzing the Doppler-shifted γ-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction O18(7.0MeV/u)+Ta181. The requested sensitivity could only be reached owing to the excellent performances of the Advanced γ-Tracking Array AGATA, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The experimental lifetimes agree with predictions of ab initio calculations using two- and three-nucleon interactions, obtained with the valence-space in-medium similarity renormalization group for O20 and with the no-core shell model for C16. The present measurement shows the power of electromagnetic observables, determined with high-precision γ spectroscopy, to assess the quality of first-principles nuclear structure calculations, complementing common benchmarks based on nuclear energies. The proposed experimental approach will be essential for short lifetime measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense beams, produced by Isotope Separation On-Line (ISOL) techniques, become available. To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2+ state in neutron-rich 20O, tau(2+_2 ) = 150(+80-30) fs, and an estimate for the lifetime of the second 2+ state in 16C have been obtained, for the first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure nuclear state lifetimes in the tens-to-hundreds femtoseconds range, by analyzing the Doppler-shifted gamma-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction 18O (7.0 MeV/u) + 181Ta. The requested sensitivity could only be reached owing to the excellent performances of the AGATA gamma-tracking array, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The experimental lifetimes agree with predictions of ab initio calculations using two- and three-nucleon interactions, obtained with the valence-space in-medium similarity renormalization group for 20O, and with the no-core shell model for 16C. The present measurement shows the power of electromagnetic observables, determined with high-precision gamma spectroscopy, to assess the quality of first-principles nuclear structure calculations, complementing common benchmarks based on nuclear energies. The proposed experimental approach will be essential for short lifetimes measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense ISOL-type beams become available.
Published: 2020

31. Evaluation of the $^{13}$N($\alpha$,p)$^{16}$O thermonuclear reaction rate and its impact on the isotopic composition of supernova grains

Author: Meyer, A., de Séréville, N., Laird, A. M., Hammache, F., Longland, R., Lawson, T., Pignatari, M., Audouin, L., Beaumel, D., Fortier, S., Kiener, J., Lefebvre-Schuhl, A., Pellegriti, M. G., Stanoiu, M., Tatischeff, V., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM)
Subjects: Astrophysics - Solar and Stellar Astrophysics, Nuclear Astrophysics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Nuclear Experiment
Abstract: International audience; Background: It has been recently suggested that hydrogen ingestion into the helium shell of massive stars could lead to high C13 and N15 excesses when the shock of a core-collapse supernova passes through its helium shell. This prediction questions the origin of extremely high C13 and N15 abundances observed in rare presolar SiC grains which is usually attributed to classical novae. In this context the N13(α,p)O16 reaction plays an important role since it is in competition with N13β+ decay to C13. Purpose: The N13(α,p)O16 reaction rate used in stellar evolution calculations comes from the Caughlan and Fowler compilation with very scarce information on the origin of this rate and with no associated uncertainty. The goal of this work is to provide a recommended N13(α,p)O16 reaction rate, based on available experimental data, with a meaningful statistical uncertainty. Method: Unbound nuclear states in the F17 compound nucleus were studied using the spectroscopic information of the analog states in O17 nucleus that were measured at the Tandem-Alto facility using the C13(Li7,t)O17 α-particle-transfer reaction. The α-particle spectroscopic factors were derived using a finite-range distorted-wave Born approximation analysis. This spectroscopic information was used to calculate a recommended N13(α,p)O16 reaction rate with meaningful uncertainty using a Monte Carlo approach. Results: The N13(α,p)O16 reaction rate from the present work is found to be within a factor of two of the previous evaluation in the temperature range of interest, with a typical uncertainty of a factor ≈2–3. The source of this uncertainty has been identified to come from the three main contributing resonances at Erc.m.=221, 741, and 959 keV. This new error estimation translates to an overall uncertainty in the C13 production of a factor of 50 when using the lower and upper reaction rates in the conditions relevant for the N13(α,p)O16 activation. Conclusions: The main source of uncertainty on the re-evaluated N13(α,p)O16 reaction rate currently comes from the uncertain α-particle width of relevant F17 states.
Published: 2020

32. Normal and intruder configurations in $^{34}$Si populated in the $β^-$ decay of $^{34}$Mg and $^{34}$Al

Author: Lica, R, Rotaru, F, Borge, MJG, Grevy, S, Negoita, F, Poves, A, Sorlin, O, Andreyev, AN, Borcea, R, Costache, C, Witte, H De, Fraile, LM, Greenlees, PT, Huyse, M, Ionescu, A, Kisyov, S, Konki, J, Lazarus, I, Madurga, M, Marginean, N, Marginean, R, Mihai, C, Mihai, RE, Negret, A, Nowacki, F, Page, RD, Pakarinen, J, Pucknell, V, Rahkila, P, Rapisarda, E, Serban, A, Sotty, CO, Stan, L, Stanoiu, M, Tengblad, O, Turturica, A, Duppen, P Van, Warr, N, Dessagne, Ph, Stora, T, Borcea, C, Calinescu, S, Daugas, JM, Filipescu, D, Kuti, I, Franchoo, S, Gheorghe, I, Morfouace, P, Morel, P, Mrazek, J, Pietreanu, D, Sohler, D, Stefan, I, Suvaila, R, Toma, S, and Ur, CA
Abstract: The structure of $^{34}$Si was studied through $\gamma$ spectroscopy separately in the $\beta^-$ decays of $^{34}$Mg and $^{34}$Al at the ISOLDE facility of CERN. Different configurations in $^{34}$Si were populated independently from the two recently identified $\beta$-decaying states in $^{34}$Al having spin-parity assignments $J^\pi = 4^-$ dominated by the normal configuration $\pi (d_{5/2})^{-1} \otimes \nu (f_{7/2})$ and $J^\pi = 1^+$ by the intruder configuration $\pi (d_{5/2})^{-1} \otimes \nu (d_{3/2})^{-1}(f_{7/2})^{2}$. The paper reports on spectroscopic properties of $^{34}$Si such as an extended level scheme, spin and parity assignments based on log($ft$) values and $\gamma$-ray branching ratios, absolute $\beta$ feeding intensities and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of $^{34}$Si. Large scale shell-model calculations using the {\sc sdpf-u-mix} interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of {\sc sdpf-u-mix}, the $N=20$ shell gap, the level of mixing between normal and intruder configurations for the 0$_1^+$, 0$_2^+$ and 2$_1^+$ states and the absence of triaxial deformation in $^{34}$Si.
Published: 2019

33. ß decay of in 133:γ emission from neutron-unbound states in Sn 133

Author: Piersa, M., Korgul, A., Fraile, L., Benito, J., Adamska, E., Andreyev, A. N., Álvarez-Rodríguez, R., Barzakh, A.E., Benzoni, G., Berry, T., García Borge, María José, Carmona, M., Chrysalidis, K., Correia, J.G., Costache, C., Cubiss, J.G., Day Goodacre, T., De Witte, H., Fedorov, D.V., Fedosseev, V.N., Fernández-Martínez, G., Fijalkowska, A., Fila, M., Fynbo, H., Galaviz, D., Greenlees, P.T., Grzywacz, R., Harkness-Brennan, L.J., Henrich, C., Huyse, M., Illana, A., Janas, Z., Johnston, K., Judson, D.S., Karanyonchev, V., Kicinska-Habior, M., Konki, J., Kurcewicz, J., Lazarus, I., Lică, R., Mach, H., Madurga, Miguel, Marroquín, I., Marsh, B., Martínez, M. C., Mazzocchi, C., Marginean, N., Marginean, R., Miernik, K., Mihai, C., Nácher, Enrique, Negret, A., Olaizola, B., Page, R. D., Paulaskalas, S., Pascu, S., Perea, Ángel, Pucknell, V., Rahkila, P., Rapisarda, E., Régis, J.- M., Rotaru, F., Rothe, S., Sánchez-Tembleque, V., Simpson, G., Sotty, C., Stan, L., Stanoiu, M., Stryjczyk, M., Tengblad, Olof, Turturica, A., Udías, J. M., Van Duppen, P., Vedia, V., Villa, A., Viñals, S., Wadsworth, R., Walters, W. B., Warr, N., European Organization for Nuclear Research, National Science Centre (Poland), Ministerio de Economía y Competitividad (España), Fundação para a Ciência e a Tecnologia (Portugal), European Commission, and SCOAP
Abstract: 10 pags., 8 figs., 1 tab.-- Open Access funded by Creative Commons Atribution Licence 4.0, Excited states in Sn133 were investigated through the ß decay of In133 at the ISOLDE facility. The ISOLDE Resonance Ionization Laser Ion Source (RILIS) provided isomer-selective ionization for In133, allowing us to study separately, and in detail, the ß-decay branch of In133J¿=(9/2+) ground state and its J¿=(1/2-) isomer. Thanks to the large spin difference of the two ß-decaying states of In133, it is possible to investigate separately the lower and higher spin states in the daughter, Sn133, and thus to probe independently different single-particle and single-hole levels. We report here new ¿ transitions observed in the decay of In133, including those assigned to the deexcitation of the neutron-unbound states., We acknowledge the support of the ISOLDE Collaboration and technical teams. This work was supported in part by the Polish National Science Center under Contract No. UMO-2015/18/E/ST2/00217 and under Contract No. UMO-2015/18/M/ST2/00523, by the Spanish MINECO via FPA2015-65035-P project, by the Portuguese FCT via CERN/FIS-NUC/0004/2015 and CERN-FIS-PAR-0005-2017 projects. The research leading to these results has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 654002.
Published: 2019

34. Normal and intruder configurations in $^{34}$Si populated in the $��^-$ decay of $^{34}$Mg and $^{34}$Al

Author: Lica, R., Rotaru, F., Borge, M. J. G., Grevy, S., Negoita, F., Poves, A., Sorlin, O., Andreyev, A. N., Borcea, R., Costache, C., De Witte, H., Fraile, L. M., Greenlees, P. T., Huyse, M., Ionescu, A., Kisyov, S., Konki, J., Lazarus, I., Madurga, M., Marginean, N., Marginean, R., Mihai, C., Mihai, R. E., Negret, A., Nowacki, F., Page, R. D., Pakarinen, J., Pucknell, V., Rahkila, P., Rapisarda, E., Serban, A., Sotty, C. O., Stan, L., Stanoiu, M., Tengblad, O., Turturica, A., Van Duppen, P., Warr, N., Dessagne, Ph., Stora, T., Borcea, C., Calinescu, S., Daugas, J. M., Filipescu, D., Kuti, I., Franchoo, S., Gheorghe, I., Morfouace, P., Morel, P., Mrazek, J., Pietreanu, D., Sohler, D., Stefan, I., Suvaila, R., Toma, S., and Ur, C. A.
Subjects: FOS: Physical sciences, Nuclear Experiment (nucl-ex)
Abstract: The structure of $^{34}$Si was studied through $��$ spectroscopy separately in the $��^-$ decays of $^{34}$Mg and $^{34}$Al at the ISOLDE facility of CERN. Different configurations in $^{34}$Si were populated independently from the two recently identified $��$-decaying states in $^{34}$Al having spin-parity assignments $J^��= 4^-$ dominated by the normal configuration $��(d_{5/2})^{-1} \otimes ��(f_{7/2})$ and $J^��= 1^+$ by the intruder configuration $��(d_{5/2})^{-1} \otimes ��(d_{3/2})^{-1}(f_{7/2})^{2}$. The paper reports on spectroscopic properties of $^{34}$Si such as an extended level scheme, spin and parity assignments based on log($ft$) values and $��$-ray branching ratios, absolute $��$ feeding intensities and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of $^{34}$Si. Large scale shell-model calculations using the {\sc sdpf-u-mix} interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of {\sc sdpf-u-mix}, the $N=20$ shell gap, the level of mixing between normal and intruder configurations for the 0$_1^+$, 0$_2^+$ and 2$_1^+$ states and the absence of triaxial deformation in $^{34}$Si.
Published: 2019
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35. Normal and intruder configurations in Si 34 populated in the β- Decay of Mg 34 and Al 34

Author: Lică, R., Rotaru, F., García Borge, María José, Grévy, S., Negoita, F., Poves, Alfredo, Sorlin, O., Andreyev, A. N., Borcea, R., Costache, C., De Witte, H., Fraile, Luis M., Greenlees, P.T., Huyse, M., Ionescu, A., Kisyov, S., Konki, J., Lazarus, I., Madurga, Miguel, Marginean, N., Marginean, R., Mihai, C., Mihai, R.E., Negret, A., Nowacki, F., Page, R. D., Pakarinen, J., Pucknell, V., Rahkila, P., Rapisarda, E., Serban, A., Sotty, C. O., Stan, L., Stanoiu, M., Tengblad, Olof, Turturica, A., Van Duppen, P., Warr, N., Dessagne, P., Stora, T., Borcea, C., Calinescu, S., Daugas, J.M., Filipescu, D., Kuti, I., Franchoo, S., Gheorghe, I., Morfouace, P., Morel, P., Science and Technology Facilities Council (UK), European Commission, Ministerio de Economía y Competitividad (España), National Research, Development and Innovation Office (Hungary), Federal Ministry of Education and Research (Germany), SCOAP, Research Foundation - Flanders, Executive Unit for Financing Higher Education, Research, Development and Innovation (Romania), and Belgian Science Policy Office
Abstract: 11 pags., 10 figs., 5 tabs.-- Open Access funded by Creative Commons Atribution Licence 4.0, The structure of Si34 was studied through γ spectroscopy separately in the β- decays of Mg34 and Al34 at the ISOLDE facility of CERN. Different configurations in Si34 were populated independently from the two recently identified β-decaying states in Al34 having spin-parity assignments Jπ=4- dominated by the normal configuration π(d5/2)-1 - ν(f7/2) and Jπ=1+ by the intruder configuration π(d5/2)-1 - ν(d3/2)-1(f7/2)2. The paper reports on spectroscopic properties of Si34 such as an extended level scheme, spin and parity assignments based on log(ft) values and γ-ray branching ratios, absolute β feeding intensities, and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of Si34. Large scale shell-model calculations using the SDPF-U-MIX interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of SDPF-U-MIX, the N=20 shell gap, the level of mixing between normal and intruder configurations for the 01+, 02+, and 21+ states, and the absence of triaxial deformation in Si34., This work was partially supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS-UEFISCDI project number PN-II-RU-TE- 2014-4-1455, by the Romanian IFA Grant CERN/ISOLDE, by Research Foundation Flanders (FWO-Belgium), by GOA/2015/010 (BOF KU Leuven), and by the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12). Support from the U.K. Science and Technology Facilities Council, the European Union Seventh Framework through ENSAR (Contract No. 262010), the MINECO (Spain) grants FPA2017-87568-P, FPA2015-64969-P, FPA2014-57196, FPA2015-65035-P, Programme “Centros de Excelencia Severo Ochoa” SEV-2016- 0597, the MEYS project SPIRAL2-CZ,EF16-013/0001679, the National Research, Development and Innovation Fund of Hungary via Project No. K128947, the European Regional Development Fund (Contract No. GINOP-2.3.3-15-2016- 00034), the German BMBF under contract 05P18PKCIA (ISOLDE), and “Verbundprojekt 05P2018” is also acknowledged. I.K. was supported by the National Research, Development and Innovation Office of Hungary (NKFIH), Contract No. PD 124717.
Published: 2019

36. Normal and intruder configurations in $^{34}$Si populated in the $\beta^-$ decay of $^{34}$Mg and $^{34}$Al

Author: Lica, R., Rotaru, F., Borge, M.J.G., Grevy, S., Negoita, F., Poves, A., Sorlin, O., Andreyev, A.N., Borcea, R., Costache, C., De Witte, H., Fraile, L.M., Greenlees, P.T., Huyse, M., Ionescu, A., Kisyov, S., Konki, J., Lazarus, I., Madurga, M., Marginean, N., Marginean, R., Mihai, C., Mihai, R.E., Negret, A., Nowacki, F., Page, R.D., Pakarinen, J., Pucknell, V., Rahkila, P., Rapisarda, E., Serban, A., Sotty, C.O., Stan, L., Stanoiu, M., Tengblad, O., Turturica, A., Van Duppen, P., Warr, N., Dessagne, Ph., Stora, T., Borcea, C., Calinescu, S., Daugas, J.M., Filipescu, D., Kuti, I., Franchoo, S., Gheorghe, I., Morfouace, P., Morel, P., Mrazek, J., Pietreanu, D., Sohler, D., Stefan, I., Suvaila, R., Toma, S., Ur, C.A., Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), IDS, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear Physics - Experiment, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nucl-ex, Nuclear Structure, Nuclear Experiment
Abstract: The structure of Si34 was studied through γ spectroscopy separately in the β− decays of Mg34 and Al34 at the ISOLDE facility of CERN. Different configurations in Si34 were populated independently from the two recently identified β-decaying states in Al34 having spin-parity assignments Jπ=4− dominated by the normal configuration π(d5/2)−1⊗ν(f7/2) and Jπ=1+ by the intruder configuration π(d5/2)−1⊗ν(d3/2)−1(f7/2)2. The paper reports on spectroscopic properties of Si34 such as an extended level scheme, spin and parity assignments based on log(ft) values and γ-ray branching ratios, absolute β feeding intensities, and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of Si34. Large scale shell-model calculations using the SDPF-U-MIX interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of SDPF-U-MIX, the N=20 shell gap, the level of mixing between normal and intruder configurations for the 01+, 02+, and 21+ states, and the absence of triaxial deformation in Si34. The structure of $^{34}$Si was studied through $\gamma$ spectroscopy separately in the $\beta^-$ decays of $^{34}$Mg and $^{34}$Al at the ISOLDE facility of CERN. Different configurations in $^{34}$Si were populated independently from the two recently identified $\beta$-decaying states in $^{34}$Al having spin-parity assignments $J^\pi = 4^-$ dominated by the normal configuration $\pi (d_{5/2})^{-1} \otimes \nu (f_{7/2})$ and $J^\pi = 1^+$ by the intruder configuration $\pi (d_{5/2})^{-1} \otimes \nu (d_{3/2})^{-1}(f_{7/2})^{2}$. The paper reports on spectroscopic properties of $^{34}$Si such as an extended level scheme, spin and parity assignments based on log($ft$) values and $\gamma$-ray branching ratios, absolute $\beta$ feeding intensities and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of $^{34}$Si. Large scale shell-model calculations using the {\sc sdpf-u-mix} interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of {\sc sdpf-u-mix}, the $N=20$ shell gap, the level of mixing between normal and intruder configurations for the 0$_1^+$, 0$_2^+$ and 2$_1^+$ states and the absence of triaxial deformation in $^{34}$Si.
Published: 2019

37. Towards the Limits of Existence of Nuclear Structure: Observation and First Spectroscopy of the Isotope $^{31}$K by Measuring Its Three-Proton Decay

Author: Kostyleva, D., Mukha, I., Acosta, L., Casarejos, E., Chudoba, V., Ciemny, A.A., Dominik, W., Dueñas, J.A., Dunin, V., Espino, J.M., Estradé, A., Farinon, F., Fomichev, A., Geissel, H., Gorshkov, A., Grigorenko, L.V., Janas, Z., Kamiński, G., Kiselev, O., Knöbel, R., Krupko, S., Kuich, M., Litvinov, Yu.A., Marquinez-Durán, G., Martel, I., Mazzocchi, C., Nociforo, C., Ordúz, A.K., Pfützner, M., Pietri, S., Pomorski, M., Prochazka, A., Rymzhanova, S., Sánchez-Benítez, A.M., Scheidenberger, C., Simon, H., Sitar, B., Slepnev, R., Stanoiu, M., Strmen, P., Szarka, I., Takechi, M., Tanaka, Y.K., Weick, H., Winkler, M., Winfield, J.S., Xu, X., Zhukov, M.V., Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment, Nuclear Physics
Abstract: The most-remote from stability isotope $^{31}$K, which is located four atomic mass units beyond the proton drip line, has been observed. It is unbound in respect to three-proton (${3p}$) emission, and its decays have been detected in flight by measuring trajectories of all decay products using micro-strip detectors. The $3p$-emission processes have been studied by means of angular correlations $^{28}$S+3$p$ and the respective decay vertexes. The energies of the previously-unknown ground and excited states of $^{31}$K have been determined. This provides its $3p$ separation-energy value $S_{3p}$ of $-4.6(2)$ MeV. Upper half-life limits of 10 ps of the observed $^{31}$K states have been derived from distributions of the measured decay vertexes., Comment: 6 pages, 5 figures
Published: 2019

38. Low-spin states in 80Ge populated in the β decay of the 80Ga 3- isomer

Author: Sekal, S., Fraile, L.M., Lica, R., Borge, M.J.G., Walters, W.B., Aprahamian, A., Benchouk, C., Bernards, C., Briz, J. A., Bucher, B., Chiara, C. J., Dlouhý, Z., Gheorghe, I., Ghita, D.G., Hoff, P., Jolie, J., Köster, U., Kurcewicz, W., Mach, H., Marginean, N., Marginean, R., Meliani, Z., Olaizola, B., Paziy, V., Régis, J.M., Rudigier, M., Sava, T., Simpson, G.S., Stanoiu, M., and Stroe, L.
Subjects: Astrophysics::High Energy Astrophysical Phenomena
Abstract: The structure of 80Ge has been investigated at the ISOLDE facility at CERN. A previous study reported for the first time a low-lying 0+2 intruder state at 639 keV, based on the coincidence with a previously unobserved 1764-keV γ ray, and suggested it as evidence for shape coexistence in 80Ge. We used the β decay from the 3− 22.4-keV state in 80Ga to enhance the population of low-spin states in 80Ge, including any excited 0+ level, and γγ coincidences to investigate it. We observed a 1764-keV γ ray in coincidence with strong transitions in 80Ge, thus not feeding the proposed 639-keV 0+2. No connecting transitions from previously known levels to the 639-keV and 2403-keV 2+3 states could be established either. Shell-model calculations for Ge isotopes and N=48 isotones were performed. They succeed to explain most of the experimental levels, but fail to reproduce the presence of a 0+2 state below ≈1200 keV in 80Ge. Our experimental findings and shell-model calculations are difficult to reconcile with a very low-lying 0+2 state in 80Ge.
Published: 2021

39. Statistical study of the prompt-fission γ -ray spectrum for U 238 (n, f) in the fast-neutron region STATISTICAL STUDY of the PROMPT-FISSION ... L. QI et al

Author: Qi, L., Lebois, M., Wilson, J. N., Chatillon, A., Courtin, S., Fruet, G., Georgiev, G., Jenkins, D. G., Laurent, B., Le Meur, L., Maj, A., Marini, P., Matea, I., Morris, L., Nanal, V., Napiorkowski, P., Oberstedt, A., Oberstedt, S., Schmitt, C., Serot, O., Stanoiu, M., and Wasilewska, B.
Subjects: Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Nuclear Experiment
Abstract: Prompt-fission γ-ray spectra (PFGS) have been measured for the U238(n,f) reaction using fast neutrons produced by the LICORNE directional neutron source. Fission events were detected with an ionization chamber containing actinide samples placed in the neutron beam, and the coincident prompt-fission γ rays were measured using a number of LaBr3 scintillation detectors and a cluster of nine phoswich detectors from the PARIS array. Prompt-fission γ rays (PFGs) were discriminated from prompt-fission neutrons using the time-of-flight technique over distances of around 35 cm. PFG emission spectra were measured at two incident neutron energies of 1.9 and 4.8 MeV for U238(n,f) and also for Cf252(sf) as a reference. Spectral characteristics of PFG emission, such as mean γ multiplicity and average total γ-ray energy per fission, as well as the average γ-ray energy, were extracted. The sensitivity of these results to the width of the time window and the type of spectral unfolding procedure used to correct for the detector responses was studied. Iteration methods were found to be more stable in low-statistics data sets. The measured values at En=1.9MeV were found to be the mean γ multiplicity Mγ=6.54±0.19, total released energy per fission Eγ,tot=5.25±0.20 MeV, and the average γ-ray energy ϵγ=0.80±0.04 MeV. Under similar conditions, the values at En=4.8MeV were measured to be Mγ=7.31±0.46, Eγ,tot=6.18±0.65 MeV, and ϵγ=0.84±0.11 MeV.
Published: 2018

40. Statistical study of the prompt-fission $\gamma$-ray spectrum for $^{238}\mathrm{U}(n, f$) in the fast-neutron region

Author: Qi, L., Lebois, M., Wilson, J.N., Chatillon, A., Courtin, S., Fruet, G., Georgiev, G., Jenkins, D.G., Laurent, B., Le Meur, L., Maj, A., Marini, P., Matea, I., Morris, L., Nanal, V., Napiorkowski, P., Oberstedt, A., Oberstedt, S., Schmitt, C., Serot, O., Stanoiu, M., Wasilewska, B., Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Laboratoire de physique subatomique et des technologies associées (SUBATECH), Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), CEA Cadarache, Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique)
Subjects: Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract: International audience; Prompt-fission γ-ray spectra (PFGS) have been measured for the U238(n,f) reaction using fast neutrons produced by the LICORNE directional neutron source. Fission events were detected with an ionization chamber containing actinide samples placed in the neutron beam, and the coincident prompt-fission γ rays were measured using a number of LaBr3 scintillation detectors and a cluster of nine phoswich detectors from the PARIS array. Prompt-fission γ rays (PFGs) were discriminated from prompt-fission neutrons using the time-of-flight technique over distances of around 35 cm. PFG emission spectra were measured at two incident neutron energies of 1.9 and 4.8 MeV for U238(n,f) and also for Cf252(sf) as a reference. Spectral characteristics of PFG emission, such as mean γ multiplicity and average total γ-ray energy per fission, as well as the average γ-ray energy, were extracted. The sensitivity of these results to the width of the time window and the type of spectral unfolding procedure used to correct for the detector responses was studied. Iteration methods were found to be more stable in low-statistics data sets. The measured values at En=1.9MeV were found to be the mean γ multiplicity M¯γ=6.54±0.19, total released energy per fission Eγ,tot=5.25±0.20 MeV, and the average γ-ray energy εγ=0.80±0.04 MeV. Under similar conditions, the values at En=4.8MeV were measured to be M¯γ=7.31±0.46, Eγ,tot=6.18±0.65 MeV, and εγ=0.84±0.11 MeV.
Published: 2018

41. Evolution of deformation in neutron-rich Ba isotopes up to A=150

Author: Lică, R., Benzoni, G., Rodríguez, T.R., Borge, M.J.G., Fraile, L.M., Mach, H., Morales, A.I., Madurga, M., Sotty, C.O., Vedia, V., De Witte, H., Benito, J., Bernard, R.N., Berry, T., Bracco, A., Camera, F., Ceruti, S., Charviakova, V., Cieplicka-Oryńczak, N., Costache, C., Crespi, F.C.L., Creswell, J., Fernandez-Martínez, G., Fynbo, H., Greenlees, P.T., Homm, I., Huyse, M., Jolie, J., Karayonchev, V., Köster, U., Konki, J., Kröll, T., Kurcewicz, J., Kurtukian-Nieto, T., Lazarus, I., Lund, M.V., Mărginean, N., Mărginean, R., Mihai, C., Mihai, R.E., Negret, A., Orduz, A., Patyk, Z., Pascu, S., Pucknell, V., Rahkila, P., Rapisarda, E., Regis, J.M., Robledo, L.M., Rotaru, F., Saed-Samii, N., Sánchez-Tembleque, V., Stanoiu, M., Tengblad, O., Thuerauf, M., Turturica, A., Van Duppen, P., Warr, N., Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut Laue-Langevin (ILL), ILL, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), IDS, Belgian Science Policy Office, Research Foundation - Flanders, Federal Ministry of Education and Research (Germany), Ministerio de Economía y Competitividad (España), Institute of Atomic Physics (Romania), Istituto Nazionale di Fisica Nucleare, European Commission, SCOAP, and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: nukleonit, lifetimes, nucleon distribution, widths, Nuclear Physics - Experiment, beta decay, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ydinfysiikka, nuclear structure and decays
Abstract: 12 pags., 11 figs., 3 tabs. -- Open Access funded by Creative Commons Atribution Licence 4.0, 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., The IDS Collaboration acknowledges financial support from Istituto Nazionale di Fisica Nucleare, the Italian “Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale” (PRIN), contract 2001024324 01302; the European Union seventh framework through ENSAR, contract 262010; the European Unions Horizon 2020 Framework research and innovation program under grant agreement 654002 (ENSAR2); the FATIMA-NuPNET network via the PRI-PIMNUP-2011-1338 project; the Romanian IFA grant CERN/ISOLDE and Romanian PN-II-RU-TE-2014-4-2003; the Spanish MINECO projects, reference numbers FPA2013- 41467-P, FPA2015-64969-P, FPA2015-65929, and FIS2015- 63770; Spanish grants FIS-2014-53434-P MINECO and Programa Ramon y Cajal 2012 No. 11420, MINECO grant IJCI-2014-19172, and the MINECO project FPA2014-52823- C2-1-P; the German BMBF under contract 05P15PKCIA, contract 05P15PKFNA, and “Verbundprojekt 05P2015,” the FWO-Vlaanderen (Belgium); and the IAP Belgian Science Policy (BriX network P7/12). V.Ch. and Z.P. acknowledge support by the Polish grant of Narodowe Centrum Nauki, no. 2015/18/M/ST2/00523.
Published: 2018

42. High Precision Measurement of the $^{19}$Ne Half-life using real-time digital acquisition

Author: Fontbonne, C., Ujić, P., Santos, F. de Oliveira, Fléchard, X., Rotaru, F., Achouri, N. L., Alcindor, V. Girard, Bastin, B., Boulay, F., Briand, J. B., Sánchez-Benítez, A. M., Bouzomita, H., Borcea, C., Borcea, R., Blank, B., Carniol, B., Čeliković, I., Delahaye, P., Delaunay, F., Etasse, D., Fremont, G., de France, G., Fontbonne, J. M., Grinyer, G. F., Harang, J., Hommet, J., Jevremović, A., Lewitowicz, M., Martel, I., Mrazek, J., Parlog, M., Poincheval, J., Ramos, D., Spitaels, C., Stanoiu, M., Thomas, J. C., and Toprek, D.
Subjects: Physics - Instrumentation and Detectors, FOS: Physical sciences, High Energy Physics::Experiment, Instrumentation and Detectors (physics.ins-det), Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: The half-life of $^{19}$Ne has been measured using a real-time digital multiparametric acquisition system providing an accurate time-stamp and relevant information on the detectors signals for each decay event. An exhaustive offline analysis of the data gave unique access to experimental effects potentially biasing the measurement. After establishing the influence factors impacting the measurement such as after-pulses, pile-up, gain and base line fluctuations, their effects were accurately estimated and the event selection optimized. The resulting half-life, $17.2569\pm0.0019_{(stat)}\pm0.0009_{(syst)}$~s, is the most precise up to now for $^{19}$Ne. It is found in agreement with two recent precise measurements and not consistent with the most recent one [L.J. Broussard {\it et al.}, Phys. Rev. Lett. {\bf112}, 212301 (2014)] by 3.0 standard deviations. The full potential of the technique for nuclei with half-lives of a few seconds is discussed., Comment: 11 pages, 16 figures
Published: 2017
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43. Spectroscopy of excited states of unbound nuclei $^{30}$Ar and $^{29}$Cl

Author: Xu, X. -D., Mukha, I., Grigorenko, L. V., Scheidenberger, C., Acosta, L., Casarejos, E., Chudoba, V., Ciemny, A. A., Dominik, W., Duénas-Díaz, J., Dunin, V., Espino, J. M., Estradé, A., Farinon, F., Fomichev, A., Geissel, H., Golubkova, T. A., Gorshkov, A., Janas, Z., Kamiński, G., Kiselev, O., Knöbel, R., Krupko, S., Kuich, M., Litvinov, Yu. A., Marquinez-Durán, G., Martel, I., Mazzocchi, C., Nociforo, C., Ordúz, A. K., Pfützner, M., Pietri, S., Pomorski, M., Prochazka, A., Rymzhanova, S., Sánchez-Benítez, A. M., Sharov, P., Simon, H., Sitar, B., Slepnev, R., Stanoiu, M., Strmen, P., Szarka, I., Takechi, M., Tanaka, Y. K., Weick, H., Winkler, M., and Winfield, J. S.
Subjects: Physics::Accelerator Physics, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: Several states of proton-unbound isotopes $^{30}$Ar and $^{29}$Cl were investigated by measuring their in-flight decay products, $^{28}$S+proton+proton and $^{28}$S+proton, respectively. A refined analysis of $^{28}$S-proton angular correlations indicates that the ground state of $^{30}$Ar is located at $2.45^{+0.05}_{-0.10}$ MeV above the two-proton emission threshold. The theoretical investigation of the $^{30}$Ar ground state decay demonstrates that its mechanism has the transition dynamics with a surprisingly strong sensitivity of the correlation patterns of the decay products to the two-proton decay energy of the $^{30}$Ar ground state and the one-proton decay energy as well as the one-proton decay width of the $^{29}$Cl ground state. The comparison of the experimental $^{28}$S-proton angular correlations with those resulting from Monte Carlo simulations of the detector response illustrates that other observed $^{30}$Ar excited states decay by sequential emission of protons via intermediate resonances in $^{29}$Cl. Based on the findings, the decay schemes of the observed states in $^{30}$Ar and $^{29}$Cl were constructed. For calibration purposes and for checking the performance of the experimental setup, decays of the previously-known states of a two-proton emitter $^{19}$Mg were remeasured. Evidences for one new excited state in $^{19}$Mg and two unknown states in $^{18}$Na were found., Comment: 17 pages, 16 figures
Published: 2017
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44. Identification of the crossing point at N=21 between normal and intruder configurations

Author: Lica, R, Rotaru, F, Borge, MJG, Grevy, S, Negoita, F, Poves, A, Sorlin, O, Andreyev, AN, Borcea, R, Costache, C, De Witte, H, Fraile, LM, Greenlees, PT, Huyse, M, Ionescu, A, Kisyov, S, Konki, J, Lazarus, I, Madurga, M, Marginean, N, Marginean, R, Mihai, C, Mihai, RE, Negret, A, Page, RD, Pakarinen, J, Pascu, S, Pucknell, V, Rahkila, P, Rapisarda, E, Serban, A, Sotty, CO, Stan, L, Stanoiu, M, Tengblad, O, Turturica, A, Van Duppen, P, Wadsworth, R, Warr, N, Collaboration, IDS, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), IDS, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Belgian Science Policy Office, Federal Ministry of Education and Research (Germany), SCOAP, Science and Technology Facilities Council (UK), National Authority for Scientific Research (Romania), Research Foundation - Flanders, Ministerio de Economía y Competitividad (España), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Helsinki Institute of Physics
Subjects: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], magnesium, 114 Physical sciences, 01 natural sciences, REGION, Nuclear physics, 0103 physical sciences, Nuclear Physics - Experiment, 010306 general physics, Spectroscopy, Physics, Large Hadron Collider, NUCLEI, STABILITY, Isotope, ta114, 010308 nuclear & particles physics, Island of inversion, aluminium, SHELL CLOSURE, island of inversion, MODEL, ISOTOPES, beta decay, Atomic physics, Ground state, Relative energy
Abstract: R. Lica et al. -- 6 pags., 3 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0, The β- decay of Mg34 was used to study the Al34 nucleus through γ spectroscopy at the Isotope Separator On-Line facility of CERN. Previous studies identified two β-decaying states in Al34 having spin-parity assignments Jπ=4- dominated by the normal configuration π(d5/2)-1 - ν(f7/2) and Jπ=1+ by the intruder configuration π(d5/2)-1 - ν(d3/2)-1(f7/2)2. Their unknown ordering and relative energy have been the subject of debate for the placement of Al34 inside or outside the N=20 >island of inversion.> We report here that the 1+ intruder lies only 46.6 keV above the 4- ground state. In addition, a new half-life of T1/2=44.9(4)ms, that is twice as long as the previously measured 20(10) ms, has been determined for Mg34. Large-scale shell-model calculations with the recently developed sdpf-u-mix interaction are compared with the new data and used to interpret the mechanisms at play at the very border of the N=20 island of inversion., This Rapid Communication was partially supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS-UEFISCDI Project No. PN-II-RU-TE-2014-4-1455, the Romanian IFA Grant CERN/ISOLDE, by FWO-Vlaanderen (Belgium), by GOA/2010/010 (BOF KU Leuven), and by the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12). Support from the U.K. Science and Technology Facilities Council, the European Union Seventh Framework through ENSAR (Contract No. 262010), the MINECO (Spain) Grants No. FPA2015-64969- P, No. FPA2014-57196, and No. FPA2015-65035-P, Programme “Centros de Excelencia Severo Ochoa” Program No. SEV-2012-0249, the German BMBF under Contract No. 05P15PKCIA (ISOLDE), and “Verbundprojekt 05P2015” also is acknowledged.
Published: 2017

45. High precision measurement of the $^{19}$Ne $\beta$-decay half-life using real-time digital acquisition

Author: Fontbonne, C., Ujić, P., de Oliveira Santos, F., Fléchard, X., Rotaru, F., Achouri, N.L., Girard Alcindor, V., Bastin, B., Boulay, F., Briand, J.B., Sánchez-Benítez, A.M., Bouzomita, H., Borcea, C., Borcea, R., Blank, B., Carniol, B., Čeliković, I., Delahaye, P., Delaunay, F., Etasse, D., Fremont, G., de France, G., Fontbonne, J.M., Grinyer, G.F., Harang, J., Hommet, J., Jevremović, A., Lewitowicz, M., Martel, I., Mrazek, J., Parlog, M., Poincheval, J., Ramos, D., Spitaels, C., Stanoiu, M., Thomas, J.C., Toprek, D., Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de physique corpusculaire de Caen ( LPCC ), Université de Caen Normandie ( UNICAEN ), Normandie Université ( NU ) -Normandie Université ( NU ) -Ecole Nationale Supérieure d'Ingénieurs de Caen ( ENSICAEN ), Normandie Université ( NU ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Grand Accélérateur National d'Ions Lourds ( GANIL ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Centre d'Etudes Nucléaires de Bordeaux Gradignan ( CENBG ), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 12.15.Hh, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], [ PHYS.NEXP ] Physics [physics]/Nuclear Experiment [nucl-ex], 24.80.+y, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 12.60.-i, [ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 23.40.-s
Abstract: International audience; The half-life of Ne19 was measured using a real-time digital multiparametric acquisition system, providing an accurate time stamp and relevant information on the detector signals for each decay event. An exhaustive offline analysis of the data gave unique access to experimental effects potentially biasing the measurement. After establishing the influence factors impacting the measurement such as after-pulses, pile-up, gain, and baseline fluctuations, their effects were accurately estimated and the event selection optimized. The resulting half-life, 17.2569±0.0019(stat)±0.0009(syst) s, is the most precise up to now for Ne19. It is found to be in agreement with two recent precise measurements and not consistent with the most recent one [L. J. Broussard , Phys. Rev. Lett. 112, 212301 (2014)PRLTAO0031-900710.1103/PhysRevLett.112.212301] by 3.0 standard deviations. The full potential of the technique for nuclei with half-lives of a few seconds is discussed.
Published: 2017

46. High-sensitivity study of levels in Al-30 following beta decay of Mg-30

Author: Olaizola, B, Mach, H, Fraile, LM, Benito, J, Borge, MJG, Boutami, R, Butler, PA, Dlouhy, Z, Fynbo, HOU, Hoff, P, Hyldegaard, S, Jeppesen, HB, Jokinen, A, Jollet, C, Korgul, A, Koster, U, Kroell, Th, Kurcewicz, W, Marechal, F, Mrazek, J, Nilsson, T, Plociennik, WA, Ruchowska, E, Schuber, R, Schwerdtfeger, W, Sewtz, M, Simpson, GS, Stanoiu, M, Tengblad, O, Thirolf, PG, Yordanov, Deyan, and Helsinki Institute of Physics
Subjects: NUCLEAR-DATA SHEETS, MOMENTS, Physical Sciences, Fysik, PICOSECOND LIFETIME MEASUREMENTS, NEUTRON, DESCENDANTS, RICH SODIUM ISOTOPES, 114 Physical sciences, REGION
Abstract: γ -ray and fast-timing spectroscopy were used to study levels in 30Al populated following the β− decay of 30Mg. Five new transitions and three new levels were located in 30Al. A search was made to identify the third 1+ state expected at an excitation energy of ∼2.5 MeV. Two new levels were found, at 3163.9 and 3362.5 keV, that are firm candidates for this state. Using the advanced time-delayed (ATD) βγγ (t) method we have measured the lifetime of the 243.8-keV state to be T1/2 = 15(4) ps, which implies that the 243.8-keV transition is mainly of M1 character. Its fast B(M1; 2+ → 3+) value of 0.10(3) W.u. is in very good agreement with the USD shell-model prediction of 0.090 W.u. The 1801.5-keV level is the only level observed in this study that could be a candidate for the second excited 2+ state. ispartof: Physical Review C vol:94 issue:5 pages:1-7 status: published
Published: 2016

47. Beta-delayed proton emission from 20Mg

Author: Lund, M. V., Andreyev, Andrei, Borge, M. J. G., Cederkäll, J., De Witte, H., Fraile, L. M., Fynbo, H. O. U., Greenlees, P. T., Harkness-Brennan, L. J., Howard, A. M., Huyse, M., Jonson, B., Judson, D. S., Kirsebom, O. S., Konki, J., Kurcewicz, J., Lazarus, I., Lica, R., Lindberg, S., Madurga, M., Marginean, N., Marginean, R., Marroquin, I., Mihai, C., Munch, M., Nacher, E., Negret, A., Nilsson, T., Page, R. D., Pascu, S., Perea, A., Pucknell, V., Rahkila, P., Rapisarda, E., Riisager, K., Rotaru, F., Sotty, C., Stanoiu, M., Tengblad, O., Turturica, A., Van Duppen, P., Vedia, V., Wadsworth, R., and Warr, N.
Subjects: Nuclear Experiment
Abstract: Beta-delayed proton emission from 20 Mg has been measured at ISOLDE, CERN, with the ISOLDE Decay Station (IDS) setup including both charged-particle and gamma-ray detection capabilities. A total of 27 delayed proton branches were measured including seven so far unobserved. An updated decay scheme, including three new resonances above the proton separation energy in 20 Na and more precise resonance energies, is presented. Beta-decay feeding to two resonances above the Isobaric Analogue State (IAS) in 20 Na is observed. This may allow studies of the 4032.9(2.4)keV resonance in 19 Ne through the beta decay of 20 Mg, which is important for the astrophysically relevant reaction 15O( $ \alpha$ , $ \gamma$ )19Ne . Beta-delayed protons were used to obtain a more precise value for the half-life of 20 Mg, 91.4(1.0)ms.
Published: 2016

48. Beta-delayed proton emission from Mg-20

Author: Lund, MV, Andreyev, A, Borge, MJG, Cederkall, J, De Witte, H, Fraile, LM, Fynbo, HOU, Greenlees, PT, Harkness-Brennan, LJ, Howard, AM, Huyse, M, Jonson, B, Judson, DS, Kirsebom, OS, Konki, J, Kurcewicz, J, Lazarus, I, Lica, R, Lindberg, S, Madurga, M, Marginean, N, Marginean, R, Marroquin, I, Mihai, C, Munch, M, Nacher, E, Negret, A, Nilsson, T, Page, RD, Pascu, S, Perea, A, Pucknell, V, Rahkila, P, Rapisarda, E, Riisager, K, Rotaru, F, Sotty, C, Stanoiu, M, Tengblad, O, Turturica, A, Van Duppen, P, Vedia, V, Wadsworth, R, Warr, N, and Collaboration, IDS
Published: 2016

49. First in-beam γ -ray study of the level structure of neutron-rich S 39

Author: Chapman, R., Wang, Z. M., Bouhelal, M., Haas, F., Liang, X., Azaiez, F., Behera, B. R., Burns, M., Caurier, E., Corradi, L., Curien, D., Deacon, A. N., Dombrádi, Z. s., Farnea, Enrico, Fioretto, E., Gadea, A., Hodsdon, A., Ibrahim, F., Jungclaus, A., Keyes, K., Kumar, V., Lunardi, S., Mǎrginean, N., Montagnoli, Giovanna, Napoli, D. R., Nowacki, F., Ollier, J., O'Donnell, D., Papenberg, A., Pollarolo, Giovanni, Salsac, M. D., Scarlassara, Fernando, Smith, J. F., Spohr, K. M., Stanoiu, M., Stefanini, A. M., Szilner, Suzana, Trotta, Marta, and Verney, David
Subjects: Nuclear and High Energy Physics
Abstract: The neutron-rich S39 nucleus has been studied using binary grazing reactions produced by the interaction of a 215-MeV beam of S36 ions with a thin Pb208 target. The magnetic spectrometer, PRISMA, and the γ-ray array, CLARA, were used in the measurements. Gamma-ray transitions of the following energies were observed: 339, 398, 466, 705, 1517, 1656, and 1724 keV. Five of the observed transitions have been tentatively assigned to the decay of excited states with spins up to (11/2-). The results of a state-of-the-art shell-model calculation of the level scheme of S39 using the SDPF-U effective interaction are also presented. The systematic behavior of the excitation energy of the first 11/2- states in the odd-A isotopes of sulfur and argon is discussed in relation to the excitation energy of the first excited 2+ states of the adjacent even-A isotopes. The states of S39 that have the components in their wave functions corresponding to three neutrons in the 1f7/2 orbital outside the N=20 core have also been discussed within the context of the 0 ω shell-model calculations presented here.
Published: 2016

50. Nearly degenerate isomeric states of $^{75}$Cu

Author: Petrone, C., Daugas, J.M., Simpson, G.S., Stanoiu, M., Plaisir, C., Faul, T., Borcea, C., Borcea, R., Caceres, L., Calinescu, S., Chevrier, Rémy, Gaudefroy, L., Georgiev, G., Gey, G., Kamalou, O., Negoita, F., Rotaru, F., Sorlin, O., Thomas, J.C., Horia Hulubei National Institute of Physics and Nuclear Engineering (NIPNE), IFIN-HH, DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), CSNSM SNO, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th]
Abstract: Expérience GANIL/LISE2000; International audience; The decays of two isomeric states in the neutron-rich nucleus Cu75 have been studied via delayed γ-ray spectroscopy. These states were populated by the fragmentation of a 60.4AMeV Kr86 primary beam, which impinged on a Be target at the LISE2k spectrometer of GANIL. Isomeric half-lives and branching ratios were measured, and a γ−γ coincidence analysis performed. These have allowed a revised level scheme of Cu75 to be proposed. A comparison with large-scale shell-model calculations using different effective interactions and valence spaces shows the importance of proton excitations across the Z=28 shell gap for reproducing the energy spacing between the isomeric states. The coexisting collective and single-particle properties of the (1/2−) and (3/2−) states, respectively, are similar to those of the same states in the neighboring Cu69,71,73. The small energy spacings between the (1/2−), (3/2−), and 5/2− states are responsible for the isomerism.
Published: 2016

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