Author: "P. J. Davies" / Topic: physics - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"P. J. Davies"' showing total 60 results

Start Over Author "P. J. Davies" Topic physics

60 results on '"P. J. Davies"'

1. Spectroscopy of the T = 2 mirror nuclei 48Fe/48Ti using mirrored knockout reactions

Author: F. Recchia, H. Iwasaki, Edward Simpson, D. Bazin, T. Haylett, E. Lunderberg, D. Kahl, R. Yajzey, P. C. Bender, P. J. Davies, X. Pereira-Lopez, R. Wadsworth, Brandon Elman, S. M. Lenzi, Brenden Longfellow, D. R. Napoli, N. Kobayashi, S. J. Lonsdale, Alexandra Gade, J. Belarge, M. A. Bentley, J. A. Tostevin, D. Weisshaar, L. Morris, and S. Uthayakumaar
Subjects: Physics, Nuclear and High Energy Physics, QC1-999, SHELL model, Nuclear Theory, Shell (structure), Context (language use), medicine.anatomical_structure, Excited state, medicine, Mirror nuclei, Atomic physics, Spectroscopy, Nuclear Experiment, Nucleus
Abstract: A sequence of excited states has been established for the first time in the proton-rich nucleus 48Fe (Z=26, N=22). The technique of mirrored (i.e. analogue) one-nucleon knockout reactions was applied, in which the T z = ±2 mirror pair, 48Fe/48Ti were populated via one-neutron/one-proton knockout from the secondary beams 49Fe/49V, respectively. The analogue properties of the reactions were used to help establish the new level scheme of 48Fe. The inclusive and exclusive cross sections were determined for the populated states. Large differences between the cross sections for the two mirrored reactions were observed and have been interpreted in terms of different degrees of binding of the mirror nuclei and in the context of the recent observations of suppression of spectroscopic strength as a function of nuclear binding, for knockout reactions on light solid targets. Mirror energy differences (MED) have been determined between the analogue T = 2 states and compared with the shell model predictions. MED for this mirror pair, due to their location in the shell, are especially sensitive to excitations out of the f 7 / 2 shell, and present a stringent test of the shell-model prescription.
Published: 2021

2. Search for in-band transitions in the candidate superdeformed band in 28Si

Author: R. G. T. Zegers, Johann Isaak, A. Bracco, B. Wasilewska, S. Zhu, T. H. Hoang, X. H. Zhou, J. J. Carroll, S. Adachi, C. Sullivan, M. P. Carpenter, M. Kumar Raju, Atsushi Tamii, L. Morris, Y. D. Fang, J. Schmitt, Shumpei Noji, N. Ichige, P. J. Davies, D. G. Jenkins, Eiji Ideguchi, G. Gey, Deniz Savran, Nobumichi Kobayashi, P. Adsley, S. Courtin, G. Fruet, Hooi Jin Ong, P. von Neumann-Cosel, A. S. Brown, Takeshi Koike, D. Montanari, A. Inoue, Nori Aoi, Hisanori Fujita, M.N. Harakeh, C. Iwamoto, V. Werner, Yasuo Yamamoto, M. L. Liu, M. Weinert, F. C. L. Crespi, Université de Strasbourg (UNISTRA), 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: Physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, 0103 physical sciences, Astrophysics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010306 general physics, 01 natural sciences
Abstract: International audience; Background: Superdeformed (SD) bands are suggested by theory around Ca40 and in lighter alpha-conjugate nuclei such as Mg24, Si28, and S32. Such predictions originate from a number of theoretical models including mean-field models and antisymmetrized molecular dynamics (AMD) calculations. While SD bands have been identified in Ca40 and its near neighbors, evidence of their existence in the lighter, midshell nuclei is circumstantial at best. The key evidence of superdeformation would be the observation of transitions with high B(E2) transition strengths connecting states in a rotational sequence. This is challenging information to obtain since the bands lie at a high excitation energy and competition from out-of-band decay is dominant.Purpose: The purpose of the present study is to establish a new methodology to circumvent the difficulties in identifying and quantifying in-band transitions through directly populating candidate states in the SD band in Si28 through inelastic alpha scattering, selecting such states with a spectrometer, and measuring their gamma-ray decay with a large array of high-purity germanium detectors, allowing direct access to electromagnetic transition strengths.Methods: Excited states in Si28 were populated in the Si28(α,α′) reaction using a 130-MeV He4 beam from the K140 AVF cyclotron at the Research Center for Nuclear Physics. Outgoing alpha particles were analyzed using the Grand Raiden spectrometer positioned at an angle of 9.1∘ to favor the population of states with J≈4. Coincident gamma rays were detected with the CAGRA array of 12 HPGe clover detectors augmented by a set of four large LaBr3 detectors.Results: Data analysis showed that it was possible to identify additional low-energy transitions in competition with high-energy decays from excited states in Si28 in the vicinity of 10 MeV. However, while the candidate 4+ SD state at 10.944 MeV was populated, a 1148-keV transition to the candidate 2+ SD state at 9.796 MeV was not observed, and only an upper limit for its transition strength of B(E2)<43 W.u. could be established. This contradicts AMD predictions of ≈200 W.u. for such a transition.Conclusion: The present study strongly rejects the hypothesis that the candidate set of states identified in Si28 represents an SD band, which demonstrates the potential of the methodology devised here.
Published: 2021
Full Text: View/download PDF

3. The structure of low-lying 1− states in 90,94Zr from (α,α′γ) and (p,p′γ) reactions

Author: Miao Liu, T. Hashimoto, J.M. Schmitt, X. K. Zhou, O. Wieland, C. Iwamoto, Norbert Pietralla, B. Wasilewska, S. Zhu, A. Czeszumska, Johann Isaak, T. Klaus, C. Sullivan, A. Inoue, M.K. Raju, Y.D. Fang, Nobuyuki Kobayashi, F. Camera, Yoshihisa Yamamoto, Shumpei Noji, V. Werner, A. Maj, G. Gey, D. G. Jenkins, Hooi Jin Ong, M. Krzysiek, F. C. L. Crespi, Andreas Zilges, M. Ciemała, L. Morris, R. G. T. Zegers, Takeshi Koike, T. Yamamoto, M. P. Carpenter, G. Steinhilber, D. L. Balabanski, A. Bracco, S. Bassauer, V. Derya, Nori Aoi, J. J. Carroll, E.G. Lanza, M. Spieker, A. S. Brown, N. Ichige, Deniz Savran, H. Fujita, S. G. Pickstone, N. Blasi, P. J. Davies, P. von Neumann Cosel, M.N. Harakeh, H.T. Ha, Atsushi Tamii, M. Weinert, L. M. Donaldson, Eiji Ideguchi, and Research unit Nuclear & Hadron Physics
Subjects: Physics, Nuclear and High Energy Physics, Range (particle radiation), Inelastic scattering, Isovector, Proton, 010308 nuclear & particles physics, Isoscalar, Binding energy, 01 natural sciences, Dipole excitation around neutron threshold, lcsh:QC1-999, Dipole, 0103 physical sciences, Neutron, Sum rule in quantum mechanics, Nuclear structure, Atomic physics, 010306 general physics, lcsh:Physics
Abstract: The low-lying dipole strength in the 90,94Zr nuclei was investigated via (p,p′γ) at 80 MeV and (α,α′γ) at 130 MeV. The experiments, made at RCNP, used the magnetic spectrometer Grand Raiden for the scattered particles and the array CAGRA with HPGe detectors for the γ-decay. For 94Zr these are the first data for both reactions and for 90Zr these are the first data with (p,p′γ) and the first ones at high resolution for (α,α′γ). The comparison of the present results for the two nuclei with existing (γ,γ′) data shows that both nuclear probes produce an excitation pattern different than that of the electromagnetic probes. DWBA calculations were made using form factors deduced from transition densities, based on RPA calculations, characterized by a strong neutron component at the nuclear surface. A combined analysis of the two reactions was performed for the first time to investigate the isoscalar character of the 1− states in 90,94Zr. The (p,p′γ) cross section was calculated using values for the isoscalar electric dipole energy-weighted sum rule (E1 ISEWSR) obtained from the (α,α′γ) data. The isoscalar strength for 90Zr was found to exhaust 20 ± 2.5% of the EWSR in the energy range up to 12 MeV. In case of 94Zr, a strength of 9 ± 1.1% of the EWSR was found in the range up to 8.5 MeV. Although an overall general description was obtained in the studied energy intervals, not all proton cross sections were well reproduced using the isoscalar strength from (α,α′γ). This might suggest mixing of isoscalar and isovector components and that this mixing and the degree of collectivity are not the same for all the 1− states below the particle binding energy.
Published: 2021

4. Shape Changes in the Mirror Nuclei Kr70 and Se70

Author: B. Blank, E. Sahin, D. T. Doherty, W. Korten, A. Obertelli, A. Boso, Tomás R. Rodríguez, Hiroyoshi Sakurai, P. Doornenbal, T. Motobayashi, D. G. Jenkins, David Steppenbeck, G. de Angelis, J. Gerl, Roman Gernhäuser, J. Libert, P. Aguilera, J. P. Delaroche, L. Sinclair, Alejandro Algora, P. J. Davies, Michel Girod, T. Saito, D. Lubos, Toshiaki Ando, Ryo Taniuchi, Si-Ge Chen, M. Zielińska, S. Nagamine, H. Baba, R. Wadsworth, Berta Rubio, Shoko Koyama, A. Corsi, Kathrin Wimmer, Megumi Niikura, and T. Arici
Subjects: Physics, Nuclear Theory, Nuclear structure, Stochastic matrix, General Physics and Astronomy, Order (ring theory), Inelastic scattering, 01 natural sciences, Matrix (mathematics), Isospin, 0103 physical sciences, Mirror nuclei, Atomic physics, Anomaly (physics), Nuclear Experiment, 010306 general physics
Abstract: We studied the proton-rich T_{z}=-1 nucleus ^{70}Kr through inelastic scattering at intermediate energies in order to extract the reduced transition probability, B(E2;0^{+}→2^{+}). Comparison with the other members of the A=70 isospin triplet, ^{70}Br and ^{70}Se, studied in the same experiment, shows a 3σ deviation from the expected linearity of the electromagnetic matrix elements as a function of T_{z}. At present, no established nuclear structure theory can describe this observed deviation quantitatively. This is the first violation of isospin symmetry at this level observed in the transition matrix elements. A heuristic approach may explain the anomaly by a shape change between the mirror nuclei ^{70}Kr and ^{70}Se contrary to the model predictions.
Published: 2021
Full Text: View/download PDF

5. Imaging neutron capture cross sections: i-TED proof-of-concept and future prospects based on Machine-Learning techniques

Author: Ignacio Porras, D. Macina, F. Ogállar, G. Cortes, G. Tagliente, A. Oprea, N. Patronis, A. K. Saxena, Claudia Lederer-Woods, Deniz Kurtulgil, Arnaud Ferrari, L. Audouin, Carlos Guerrero, S. Heinitz, R. Garg, Alberto Mengoni, I. Ladarescu, Rugard Dressler, C. Petrone, P. Torres-Sánchez, Hideo Harada, T. Rodríguez-González, J. Lerendegui-Marco, M. Sabaté-Gilarte, L. Persanti, J. Balibrea-Correa, A. Casanovas, J. Billowes, A. Tsinganis, V. Babiano-Suarez, S. Amaducci, S. Bennett, N. V. Sosnin, O. Aberle, Nicola Colonna, Luis Caballero, M. A. Millán-Callado, Simone Gilardoni, I. F. Gonçalves, A. Stamatopoulos, V. Variale, A. Kimura, Dimitri Rochman, Arnd R. Junghans, Annamaria Mazzone, L. Cosentino, A. Masi, Petar Žugec, M. Mastromarco, D. Bosnar, D. G. Jenkins, Z. Eleme, E. Dupont, Emilio Andrea Maugeri, D. Cano-Ott, P. Sprung, E. Mendoza, Massimo Barbagallo, Y. Kadi, Anton Wallner, Kathrin Göbel, M. Kokkoris, A. Sekhar, M. Diakaki, Y. Kopatch, I. Duran, A. Manna, A. Gawlik, Thomas Rauscher, Jan Heyse, D. Ramos-Doval, Diego Vescovi, Maurizio Busso, J. Andrzejewski, J. Moreno-Soto, M. Bacak, M. A. Cortés-Giraldo, Rene Reifarth, F. Mingrone, G. Vannini, D. Calvo, Paolo Finocchiaro, V. Vlachoudis, M. Krtička, Ariel Tarifeño-Saldivia, S. J. Lonsdale, Dorothea Schumann, I. Knapova, J. M. Quesada, L. Tassan-Got, Alexandru Negret, S. Valenta, T. Martinez, E. Pirovano, B. Fernández-Domínguez, A. S. Brown, P. Vaz, Sergio Cristallo, Marco Calviani, E. González-Romero, F. Käppeler, A. G. Smith, D. Real, L. A. Damone, M. Caamaño, Alberto Ventura, M. Dietz, V. Alcayne, F. Calviño, H. Leeb, A. Musumarra, Philip Woods, A. Pavlik, E. Chiaveri, J. Perkowski, P. F. Mastinu, P. M. Milazzo, C. Domingo-Pardo, F. Cerutti, J. L. Tain, F. Gunsing, Th. Thomas, Cristian Massimi, S. Urlass, P. J. Davies, R. Vlastou, V. Michalopoulou, J. Ulrich, Peter Schillebeeckx, E. Berthoumieux, C. Rubbia, Q. Ducasse, Javier Praena, V. Furman, T. J. Wright, ITA, GBR, FRA, DEU, ESP, AUS, AUT, BEL, HRV, GRC, IND, POL, CZE, European Commission, Ministerio de Ciencia, Innovación y Universidades (España), Consejo Superior de Investigaciones Científicas (España), 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Babiano-Su??rez, V., Lerendegui-Marco, J., Balibrea-Correa, J., Caballero, L., Calvo, D., Ladarescu, I., Real, D., Domingo-Pardo, C., Calvi??o, F., Casanovas, A., Tarife??o-Saldivia, A., Alcayne, V., Guerrero, C., Mill??n-Callado, M. A., Rodr??guez-Gonz??lez, T., Barbagallo, M., Aberle, O., Amaducci, S., Andrzejewski, J., Audouin, L., Bacak, M., Bennett, S., Berthoumieux, E., Billowes, J., Bosnar, D., Brown, A., Busso, M., Caama??o, M., Calviani, M., Cano-Ott, D., Cerutti, F., Chiaveri, E., Colonna, N., Cort??s, G., Cort??s-Giraldo, M. A., Cosentino, L., Cristallo, S., Damone, L. A., Davies, P. J., Diakaki, M., Dietz, M., Dressler, R., Ducasse, Q., Dupont, E., Dur??n, I., Eleme, Z., Fern??ndez-Dom??nguez, B., Ferrari, A., Finocchiaro, P., Furman, V., G??bel, K., Garg, R., Gawlik, A., Gilardoni, S., Gon??alves, I. F., Gonz??lez-Romero, E., Gunsing, F., Harada, H., Heinitz, S., Heyse, J., Jenkins, D. G., Junghans, A., K??ppeler, F., Kadi, Y., Kimura, A., Knapova, I., Kokkoris, M., Kopatch, Y., Krti??ka, M., Kurtulgil, D., Lederer-Woods, C., Leeb, H., Lonsdale, S. J., Macina, D., Manna, A., Martinez, T., Masi, A., Massimi, C., Mastinu, P., Mastromarco, M., Maugeri, E. A., Mazzone, A., Mendoza, E., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Mingrone, F., Moreno-Soto, J., Musumarra, A., Negret, A., Og??llar, F., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., Persanti, L., Petrone, C., Pirovano, E., Porras, I., Praena, J., Quesada, J. M., Ramos-Doval, D., Rauscher, T., Reifarth, R., Rochman, D., Rubbia, C., Sabat??-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Sekhar, A., Smith, A. G., Sosnin, N. V., Sprung, P., Stamatopoulos, A., Tagliente, G., Tain, J. L., Tassan-Got, L., Thomas, Th., Torres-S??nchez, P., Tsinganis, A., Ulrich, J., Urlass, S., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vescovi, D., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T., and ugec, P.
Subjects: Astrophysics and Astronomy, Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Physics: Instrumentation and Detectors, Astrophysics, Instrumentation and Methods for Astrophysics, Nuclear Experiment, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nucl-ex, Astrophysics, 01 natural sciences, 0103 physical sciences, Electronic engineering, Nuclear Physics - Experiment, Sensitivity (control systems), [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Detectors and Experimental Techniques, Nuclear Experiment (nucl-ex), 010306 general physics, physics.ins-det, Nuclear Experiment, Instrumentation and Methods for Astrophysics (astro-ph.IM), Physics::Atmospheric and Oceanic Physics, Physics, Large Hadron Collider, i-TED, neutron capture, n_TOF, machine learning, 010308 nuclear & particles physics, Compton imaging, Detector, Experimental validation, Instrumentation and Detectors (physics.ins-det), Neutron capture, Physics: Instrumentation and Detectors, Proof of concept, Benchmark (computing), Instrumentation and Methods for Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, astro-ph.IM
Abstract: Babiano-Suárez, V., et al., i-TED is an innovative detection system which exploits Compton imaging techniques to achieve a superior signal-to-background ratio in (n, γ) cross-section measurements using time-of-flight technique. This work presents the first experimental validation of the i-TED apparatus for high-resolution time-of-flight experiments and demonstrates for the first time the concept proposed for background rejection. To this aim, the Au(n, γ) and Fe(n, γ) reactions were studied at CERN n_TOF using an i-TED demonstrator based on three position-sensitive detectors. Two CD detectors were also used to benchmark the performance of i-TED. The i-TED prototype built for this study shows a factor of ∼ 3 higher detection sensitivity than state-of-the-art CD detectors in the 10 keV neutron-energy region of astrophysical interest. This paper explores also the perspectives of further enhancement in performance attainable with the final i-TED array consisting of twenty position-sensitive detectors and new analysis methodologies based on Machine-Learning techniques., This work has been carried out in the framework of a project funded by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC Consolidator Grant project HYMNS, with grant agreement No. 681740). The authors acknowledge support from the Spanish Ministerio de Ciencia e Innovación under grants PID2019-104714GB-C21, FPA2017-83946-C2-1-P, FIS2015-71688-ERC, CSIC for funding PIE-201750I26, and the funding agencies of the participating institutes. We would like to thank the crew at the Electronics Laboratory of IFIC, in particular Manuel Lopez Redondo and Jorge Nácher Arándiga for their excellent and efficient work.
Published: 2021
Full Text: View/download PDF

6. Lifetimes of core-excited states in semi-magic $$^{95}\mathrm {Rh}$$

Author: G. de Angelis, Eric Clément, Bo Cederwall, H. Al Azri, Mikael Sandzelius, Ulrika Jakobsson, C. M. Petrache, Chong Qi, S. S. Ghugre, V. Modamio, Zhigang Xiao, F. Ghazi Moradi, S. Erturk, G. Jaworski, Baki Akkuş, A. Algora, A. Ertoprak, M. Palacz, M. Doncel, C. Michelagnoli, Torbjörn Bäck, Eiji Ideguchi, A. Boso, H. W. Li, J. J. Valiente-Dobón, M. Siciliano, Zs. Dombradi, A. Gadea, T. Hüyük, Johan Nyberg, F. Recchia, R. Wadsworth, B. M. Nyakó, P. J. Davies, István Kuti, D. M. Debenham, D. R. Napoli, D. Sohler, A. Gottardo, János Timár, R. Raut, A. Atac, Department of Physics [Stockholm], Royal Institute of Technology [Stockholm] (KTH ), 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), 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 Department of Physics, Royal Institute of Technology (KTH), 10691 Stockholm, Sweden
Subjects: [PHYS]Physics [physics], Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Hadron, 01 natural sciences, Core (optical fiber), symbols.namesake, Excited state, 0103 physical sciences, symbols, Nuclear fusion, Neutron, MAGIC (telescope), Atomic physics, 010306 general physics, Doppler effect, Line (formation)
Abstract: Lifetimes of negative-parity states have been determined in the neutron deficient semi-magic (N = 50) nucleus $$^{95}\mathrm {Rh}$$ 95 Rh . The fusion-evaporation reaction $$^{58}Ni(^{40}Ca, 3p)$$ 58 N i ( 40 C a , 3 p ) was used to populate high-spin states in $$^{95}\mathrm {Rh}$$ 95 Rh at the Grand Accélérateur National d’Ions Lourds (GANIL) accelerator facility. The results were obtained using the Doppler Shift Attenuation Method (DSAM) based on the Doppler broadened line shapes produced during the slowing down process of the residual nuclei in a thick $$6\;\mathrm {mg/cm}^2$$ 6 mg / cm 2 metallic target. B(M1) and B(E2) reduced transition strengths are compared with predictions from large-scale shell-model calculations.
Published: 2020
Full Text: View/download PDF

7. Fission Fragment Atomic Number Measurements Using Bragg Detectors

Author: Ulli Köster, B. S. Nara Singh, A. G. Smith, R.L. Kennedy-Reid, P. J. Davies, Nikolay Sosnin, Tobias Wright, and Aurelien Blanc
Subjects: Physics, Nuclear and High Energy Physics, Proton, Physics::Instrumentation and Detectors, Fission, Fragment (computer graphics), Detector, Effective nuclear charge, Lohengrin, fission fragment range, SRIM, ionization chamber, Ionization chamber, Microchannel plate detector, Atomic number, Atomic physics, Nuclear Experiment, Instrumentation, fission fragment charge, sub-Bragg peak spectroscopy
Abstract: A Bragg detector with a Frisch grid and 1 metre-long time-of-flight section with microchannel plate assemblies was characterized at the Lohengrin fission fragment separator at the Institut Laue-Langevin (ILL) by measuring 235U fission fragments of selected masses and energies at the Lohengrin focal plane. The aim of the measurements was to investigate the response of Bragg detectors to differing nuclear charge states. Energy-loss and a signal-risetime dependent parameters were defined and extracted from the accumulated signal pulse shapes, and their behaviour as a function of fragment velocity was investigated. The experimental results are compared to a SRIM-2013 simulation. Measurements of fission fragment ranges in isobutane are presented. Average proton numbers for measured fragment masses were identified and could be resolved by the parameters, which exhibited monotonic variation with charge. The results differed from SRIM both in trends and in values, with SRIM simulations exhibiting non-monotonic behaviour with proton number.
Published: 2020
Full Text: View/download PDF

8. Review and new concepts for neutron-capture measurements of astrophysical interest

Author: M. Sabaté-Gilarte, A. Kimura, A. Segarr, J. Lerendegui-Marco, M. Krtička, T. Martinez, M. Busso, M. Mastromarco, L. Caballero, J. L. Tain, G. Tagliente, Mario Barbagallo, Z. Eleme, D. Schumann, I. Knapova, S. Bennett, B. Fernandez-Domingez, G. Vannini, P. Vaz, P. Sprung, A. Masi, F. Ogallar, A. Saxena, F. Gunsing, V. Michalopoulou, J. Heyse, A. Stamatopoulos, N. Patronis, A. Casanovas, D. G. Jenkins, Alberto Ventura, E. Jericha, E. Berthoumieux, Javier Praena, B. Thomas, A. Negret, Cristian Massimi, Alberto Mengoni, I. Ferro-Goncalves, P. J. Davies, M. A. Cortés-Giraldo, C. Rubbia, P. M. Milazzo, Paolo Finocchiaro, G. Cortes, D. R. Doval, E. Mendoza, S. Urlass, Alfredo Ferrari, J. Balibrea-Correa, J. Moreno-Soto, D. Rochman, L. Cosentino, N. V. Sosnin, A. Mazzone, M. Kokkoris, E. Maugeri, P. F. Mastinua, A. Oprea, Rene Reifarth, C. Petrone, Claudia Lederer-Woods, V. Variale, Arnd R. Junghans, P. Torres-Sanchez, A. Sekhar, M. Diakaki, U. Jiri, F. Mingrone, S. Amaducci, M. Bacak, J. M. Quesada, L. Tassan-Got, Deniz Kurtulgil, J. Andrzejewski, M. Caamaño, E. Chiaveri, V. Babiano-Suarez, D. Cano-Ott, D. Macina, F. Cerutti, V. Vlachoudis, I. Ladarescu, L. Audouin, Carlos Guerrero, L. Piersanti, A. Pavlik, A. S. Brown, R. Garg, C. Domingo-Pardo, E. González-Romero, I. Porras, Ariel Tarifeño-Saldivia, S. J. Lonsdale, M. T. Rodriguez-Gonzalez, O. Aberle, V. Furman, Y. Kopatch, A. Tsinganis, Simone Gilardoni, F. Calviño, E. Pirovano, Nicola Colonna, J. Perkowski, E. Dupont, M. A. Millán-Callado, K. Göbel, S. Cristallo, T. Wright, Diego Vescovi, F. Käppeler, A. Musumarra, R. Vlastou, Damir Bosnar, Y. Kadi, A. Manna, Q. Ducasse, S. Valenta, P. Zugec, Marco Calviani, A. G. Smith, M. Dietz, Philip Woods, Anton Wallner, P. Schillebeeckx, A. Gawlik, L. A. Damone, I. Duran, R. Dressler, V. Alcayne, 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 de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, n_TOF, 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), Domingo-Pardo, C., Babiano-Suarez, V., Balibrea-Correa, J., Caballero, L., Ladarescu, I., Lerendegui-Marco, J., Tain, J. L., Calvino, F., Casanovas, A., Segarr, A., Tarifeno-Saldivia, A. E., Guerrero, C., Millan-Callado, M. A., Quesada, J. M., Rodriguez-Gonzalez, M. T., Aberle, O., Alcayne, V., Amaducci, S., Andrzejewski, J., Audouin, L., Bacak, M., Barbagallo, M., Bennett, S., Berthoumieux, E., Bosnar, D., Brown, A. S., Busso, M., Caamano, M., Calviani, M., Cano-Ott, D., Cerutti, F., Chiaveri, E., Colonna, N., Cortes, G. P., Cortes-Giraldo, M. A., Cosentino, L., Cristallo, S., Damone, L. A., Davies, P. J., Diakaki, M., Dietz, M., Dressler, R., Ducasse, Q., Dupont, E., Duran, I., Eleme, Z., Fernandez-Domingez, B., Ferrari, A., Ferro-Goncalves, I., Finocchiaro, P., Furman, V., Garg, R., Gawlik, A., Gilardoni, S., Gobel, K., Gonzalez-Romero, E., Gunsing, F., Heyse, J., Jenkins, D. G., Jericha, E., Jiri, U., Junghans, A., Kadi, Y., Kappeler, F., Kimura, A., Knapova, I., Kokkoris, M., Kopatch, Y., Krticka, M., Kurtulgil, D., Lederer-Woods, C., Lonsdale, S. -J., Macina, D., Manna, A., Martinez, T., Masi, A., Massimi, C., Mastinua, P. F., Mastromarco, M., Maugeri, E., Mazzone, A., Mendoza, E., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Mingrone, F., Moreno-Soto, J., Musumarra, A., Negret, A., Ogallar, F., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., Petrone, C., Piersanti, L., Pirovano, E., Porras, I., Praena, J., Doval, D. R., Reifarth, R., Rochman, D., Rubbia, C., Sabate-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Sekhar, A., Smith, A. G., Sosnin, N., Sprung, P., Stamatopoulos, A., Tagliente, G., Tassan-Got, L., Thomas, B., Torres-Sanchez, P., Tsinganis, A., Urlass, S., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vescovi, D., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T. J., Zugec, P., Domingo-Pardo C., Babiano-Suarez V., Balibrea-Correa J., Caballero L., Ladarescu I., Lerendegui-Marco J., Tain J.L., Calvino F., Casanovas A., Segarr A., Tarifeno-Saldivia A.E., Guerrero C., Millan-Callado M.A., Quesada J.M., Rodriguez-Gonzalez M.T., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Bacak M., Barbagallo M., Bennett S., Berthoumieux E., Bosnar D., Brown A.S., Busso M., Caamano M., Calviani M., Cano-Ott D., Cerutti F., Chiaveri E., Colonna N., Cortes G.P., Cortes-Giraldo M.A., Cosentino L., Cristallo S., Damone L.A., Davies P.J., Diakaki M., Dietz M., Dressler R., Ducasse Q., Dupont E., Duran I., Eleme Z., Fernandez-Domingez B., Ferrari A., Ferro-Goncalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Gobel K., Gonzalez-Romero E., Gunsing F., Heyse J., Jenkins D.G., Jericha E., Jiri U., Junghans A., Kadi Y., Kappeler F., Kimura A., Knapova I., Kokkoris M., Kopatch Y., Krticka M., Kurtulgil D., Lederer-Woods C., Lonsdale S.-J., Macina D., Manna A., Martinez T., Masi A., Massimi C., Mastinua P.F., Mastromarco M., Maugeri E., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P.M., Mingrone F., Moreno-Soto J., Musumarra A., Negret A., Ogallar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Doval D.R., Reifarth R., Rochman D., Rubbia C., Sabate-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A.G., Sosnin N., Sprung P., Stamatopoulos A., Tagliente G., Tassan-Got L., Thomas B., Torres-Sanchez P., Tsinganis A., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P.J., Wright T.J., and Zugec P.
Subjects: History, Physics - Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Measure (physics), FOS: Physical sciences, General Physics and Astronomy, 7. Clean energy, 01 natural sciences, Education, Nuclear physics, Nucleosynthesis, 0103 physical sciences, Neutron, 14. Life underwater, Instrumentation (computer programming), [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Detectors and Experimental Techniques, 010306 general physics, physics.ins-det, 010303 astronomy & astrophysics, Stellar evolution, Physics, neutron capture, detector, TOF, Detector, Instrumentation and Detectors (physics.ins-det), Computer Science Applications, Progressive refinement, Neutron capture, astrophysics, neutron capture, neutron time of flight, n_TOF
Abstract: The idea of slow-neutron capture nucleosynthesis formulated in 1957 triggered a tremendous experimental effort in different laboratories worldwide to measure the relevant nuclear physics input quantities, namely (n, γ) cross sections over the stellar temperature range (from few eV up to several hundred keV) for most of the isotopes involved from Fe up to Bi. A brief historical review focused on total energy detectors will be presented to illustrate how advances in instrumentation have led to the assessment of new aspects of s-process nucleosynthesis and to the progressive refinement of stellar models. A summary will be presented on current efforts to develop new detection concepts, such as the Total-Energy Detector with γ-ray imaging capability (i-TED). The latter is based on the simultaneous combination of Compton imaging with neutron time-of-flight (TOF) techniques, in order to achieve a superior level of sensitivity and selectivity in the measurement of stellar neutron capture rates., European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (ERC Consolidator Grant project HYMNS) 681740, Instituto de Salud Carlos III Spanish Government FPA2014-52823-C2-1-P FPA2017-83946-C2-1-P, Consejo Superior de Investigaciones Cientificas (CSIC) PIE-201750I26, Program Severo Ochoa SEV-2014-0398
Published: 2020
Full Text: View/download PDF

9. Studying the Exotic Decay $^{70}Kr$ $\rightarrow$ $^{70}Br$

Author: Daiki Nishimura, G. de Angelis, Hiroyoshi Sakurai, Y. Shimizu, P. A. Söderström, Shunji Nishimura, S. Yagi, C. Magron, J. Agramunt, V. Guadilla, JJ Liu, H. Oikawa, S. M. Lenzi, Y. Takei, N. Kurz, W. Gelletly, S. Chen, A. I. Morales, F. Recchia, E. Ganioglu, J. Giovinazzo, H. Baba, Y. Fujita, V. H. Phong, Gabor Kiss, F. Diel, T. Goigoux, H. Suzuki, D. S. Ahn, Zs. Dombradi, T. Kurtukian Nieto, Jin Wu, P. Aguilera, J. Eberth, N. Fukuda, Jenny Lee, B. Rubio, F. Molina, T. Isobe, P. J. Davies, I. Kojouharov, P. Ascher, M. Tanaka, Alejandro Algora, Naohito Inabe, B. Blank, Toshiyuki Sumikama, Hiroyuki Takeda, S. E.A. Orrigo, P. Doornebal, A. Montaner-Pizá, D. Lubos, C. Borcea, D. R. Napoli, M. Gerbaux, H. Shaffner, S. Grévy, W. Korten, A. Horvath, Toshiyuki Kubo, A. Boso, Shigeru Kubono, A. Vitez-Sveiczer, T. Lokotko, 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), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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), 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 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: Nuclear physics, Physics, 010308 nuclear & particles physics, 0103 physical sciences, General Physics and Astronomy, ddc:530, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences
Abstract: Acta physica Polonica / B 51(3), 587 (2020). doi:10.5506/APhysPolB.51.587, Published by Inst. of Physics, Jagellonian Univ., Cracow
Published: 2020
Full Text: View/download PDF

10. First results of the 241Am(n,f) cross section measurement at the Experimental Area 2 of the n_TOF facility at CERN

Author: M. Bacak, S. Heinitz, Y. Kadi, C. Petrone, O. Aberle, M. A. Millán-Callado, J. L. Tain, G. Cortes, M. Mastromarco, Z. Eleme, G. Vannini, M. Caamaño, P. J. Davies, A. Masi, S. Valenta, B. Fernández-Domíngez, Massimo Barbagallo, Anton Wallner, A. S. Brown, D. G. Jenkins, Marco Calviani, Rene Reifarth, B. Thomas, A. G. Smith, Alexandru Negret, J. Andrzejewski, A. Oprea, L. Audouin, F. Cerutti, F. Käppeler, J. M. Quesada, L. Tassan-Got, Emilio Andrea Maugeri, Rugard Dressler, M. Dietz, P. M. Milazzo, D. Bosnar, M. Kokkoris, V. Babiano-Suarez, Sergio Cristallo, M. A. Cortés-Giraldo, V. Alcayne, C. Rubbia, A. Tsinganis, Luciano Piersanti, A. Kimura, F. Ogállar, P. J. Woods, T. Martinez, E. Jericha, Paolo Finocchiaro, A. Manna, Nicola Colonna, E. Dupont, R. Vlastou, Vasilis Vlachoudis, Y. Kopatch, Dorothea Schumann, J. Moreno-Soto, N. Patronis, A. K. Saxena, I. Ferro-Gonçalves, Simone Gilardoni, I. Duran, G. Tagliente, Q. Ducasse, Arnaud Ferrari, L. Caballero, E. Berthoumieux, I. Ladarescu, Kathrin Göbel, U. Jiri, D. Ramos Doval, Jan Heyse, E. Chiaveri, P. F. Mastinu, A. Casanovas, D. Cano-Ott, S. Urlass, S. Bennett, A. Sekhar, M. Diakaki, A. Stamatopoulos, A. Gawlik, Javier Praena, L. Cosentino, V. Furman, T. J. Wright, N. V. Sosnin, I. Knapova, P. Vaz, Annamaria Mazzone, Petar Žugec, L. A. Damone, P. Sprung, Alberto Ventura, F. Calviño, A. Pavlik, C. Domingo-Pardo, E. Pirovano, V. Michalopoulou, J. Perkowski, E. Mendoza, E. González-Romero, F. Gunsing, Peter Schillebeeckx, Cristian Massimi, A. Mengoni, D. Macina, Carlos Guerrero, R. Garg, M. Krticˇka, Claudia Lederer-Woods, P. Torres-Sánchez, Deniz Kurtulgil, M. Sabaté-Gilarte, Maurizio Busso, Ariel Tarifeño-Saldivia, S. J. Lonsdale, Ignacio Porras, Diego Vescovi, J. Lerendegui-Marco, S. Amaducci, A. Musumarra, F. Mingrone, V. Variale, Dimitri Rochman, Arnd R. Junghans, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, CEA Cadarache, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, n_TOF, 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), Ge, Z., Shu, N., Chen, Y., Wang, W., and Zhang, H.
Subjects: Large Hadron Collider, Materials science, Nuclear transmutation, Isotope, 010308 nuclear & particles physics, n_TOF, 241Am, fission, neutron time of flight, 4. Education, Nuclear engineering, Physics, QC1-999, Radioactive waste, MicroMegas detector, Actinide, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Incineration, 13. Climate action, Neutron flux, 0103 physical sciences, Nuclear Physics - Experiment, 010306 general physics
Abstract: This research is co-financed by Greece and the European Union (European Social Fund-ESF) through the Operational Programme Human Resources Development, Education and Lifelong Learning in the context of the project "Strengthening Human Resources Research Potential via Doctorate Research" (MIS-5000432), implemented by the State Scholarships Foundation (IKY). Also, the authors would like to acknowledge the support of the European Commission under the CHANDA project (7th Framework Programme)., Feasibility, design and sensitivity studies on innovative nuclear reactors that could address the issue of nuclear waste transmutation using fuels enriched in minor actinides, require high accuracy cross section data for a variety of neutron-induced reactions from thermal energies to several tens of MeV. The isotope Am-241 (T-1/2= 433 years) is present in high-level nuclear waste (HLW), representing about 1.8 % of the actinide mass in spent PWR UOx fuel. Its importance increases with cooling time due to additional production from the beta-decay of Pu-241 with a half-life of 14.3 years. The production rate of 241Am in conventional reactors, including its further accumulation through the decay of Pu-241 and its destruction through transmutation/incineration are very important parameters for the design of any recycling solution. In the present work, the Am-241(n,f) reaction cross-section was measured using Micromegas detectors at the Experimental Area 2 of the n_TOF facility at CERN. For the measurement, the U-235(n,f) and U-238(n,f) reference reactions were used for the determination of the neutron flux. In the present work an overview of the experimental setup and the adopted data analysis techniques is given along with preliminary results., European Union (European Social Fund-ESF) through the Operational Programme Human Resources Development, Education and Lifelong Learning MIS-5000432, European Commission under the CHANDA project (7th Framework Programme)
Published: 2020
Full Text: View/download PDF

11. New reaction rates for the destruction of $^7$Be during big bang nucleosynthesis measured at CERN/n_TOF and their implications on the cosmological lithium problem

Author: Z. Eleme, M. Mastromarco, Massimo Barbagallo, I. Knapova, Anton Wallner, S. Valenta, Rugard Dressler, P. Vaz, M. Krtička, Marco Calviani, A. Gawlik, G. Vannini, A. G. Smith, A. Tsinganis, T. Martinez, V. Furman, T. J. Wright, Alberto Ventura, M. Dietz, Luciano Piersanti, M. Caamaño, Nicola Colonna, P. J. Woods, I. Ladarescu, Vasilis Vlachoudis, E. González-Romero, F. Ogállar, M. Sabaté-Gilarte, P. J. Davies, N. Patronis, A. K. Saxena, Arnaud Ferrari, L. Audouin, N. V. Sosnin, Annamaria Mazzone, Petar Žugec, G. Tagliente, D. Ramos Doval, O. Aberle, E. Chiaveri, J. Moreno-Soto, Alberto Mengoni, E. Dupont, A. Pavlik, P. Sprung, G. Cortes, P. F. Mastinu, M. A. Millán-Callado, L. A. Damone, D. Macina, Carlos Guerrero, C. Domingo-Pardo, A. Kimura, A. Casanovas, R. Garg, P. Torres-Sánchez, S. Bennett, M. Bacak, A. Stamatopoulos, A. Masi, Emilio Andrea Maugeri, L. Cosentino, J. L. Tain, D. G. Jenkins, Kathrin Göbel, Y. Kadi, F. Gunsing, I. Duran, M. Kokkoris, D. Bosnar, Jan Heyse, E. Pirovano, S. Urlass, M. A. Cortés-Giraldo, E. Jericha, Claudia Lederer-Woods, Cristian Massimi, B. Thomas, Deniz Kurtulgil, V. Alcayne, R. Vlastou, Rene Reifarth, Paolo Finocchiaro, E. Berthoumieux, Dorothea Schumann, J. M. Quesada, Y. Kopatch, L. Tassan-Got, Sergio Cristallo, C. Rubbia, Q. Ducasse, V. Michalopoulou, F. Mingrone, F. Calviño, E. Mendoza, J. Perkowski, V. Variale, Peter Schillebeeckx, Dimitri Rochman, Arnd R. Junghans, S. Heinitz, C. Petrone, I. Ferro-Gonçalves, A. S. Brown, P. M. Milazzo, B. Fernández-Domíngez, A. Oprea, Ignacio Porras, D. Cano-Ott, A. Sekhar, M. Diakaki, Maurizio Busso, Ariel Tarifeño-Saldivia, S. J. Lonsdale, J. Lerendegui-Marco, S. Amaducci, Alexandru Negret, F. Käppeler, V Babiano-Suarez, A. Manna, J. Andrzejewski, F. Cerutti, L. Caballero, Simone Gilardoni, U. Jiri, Javier Praena, Diego Vescovi, A. Musumarra, 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 de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, Ge, Z., Shu, N., Chen, Y., Wang, W., and Zhang, H.
Subjects: Physics, Range (particle radiation), Large Hadron Collider, n_TOF, 7Be, big bang nucleosynthesis, cosmological lithium problem, 010308 nuclear & particles physics, QC1-999, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Reaction rate, Nuclear physics, Big Bang nucleosynthesis, chemistry, 13. Climate action, 0103 physical sciences, Thermal, Neutron, Lithium, Nuclear Physics - Experiment, 010306 general physics, Nuclear Experiment
Abstract: New measurements of the7Be(n,α)4He and7Be(n,p)7Li reaction cross sections from thermal to keV neutron energies have been recently performed at CERN/n_TOF. Based on the new experimental results, astrophysical reaction rates have been derived for both reactions, including a proper evaluation of their uncertainties in the thermal energy range of interest for big bang nucleosynthesis studies. The new estimate of the7Be destruction rate, based on these new results, yields a decrease of the predicted cosmological7Li abundance insufficient to provide a viable solution to the cosmological lithium problem.
Published: 2020
Full Text: View/download PDF

12. Status and perspectives of the neutron time-of-flight facility n_TOF at CERN

Author: D. Bosnar, Rugard Dressler, A. Tsinganis, N. V. Sosnin, S. Bennett, A. Stamatopoulos, Luciano Piersanti, Nicola Colonna, Annamaria Mazzone, Petar Žugec, Z. Eleme, P. Sprung, F. Ogállar, A. Kimura, G. Cortes, A. Masi, V. Variale, O. Aberle, G. Tagliente, Dimitri Rochman, Arnd R. Junghans, A. Pavlik, D. Ramos Doval, D. G. Jenkins, E. Jericha, Y. Kopatch, C. Domingo-Pardo, M. A. Millán-Callado, Maurizio Busso, L. Audouin, M. Krtička, Emilio Andrea Maugeri, M. Kokkoris, Paolo Finocchiaro, Dorothea Schumann, E. Pirovano, T. Martinez, Rene Reifarth, Ariel Tarifeño-Saldivia, S. J. Lonsdale, M. A. Cortés-Giraldo, A. Casanovas, Alexandru Negret, F. Cerutti, M. Bacak, A. S. Brown, P. J. Woods, Ignacio Porras, F. Käppeler, J. Andrzejewski, I. Knapova, Y. Kadi, J. M. Quesada, D. Cano-Ott, A. Sekhar, M. Diakaki, P. Vaz, F. Gunsing, I. Ferro-Gonçalves, G. Vannini, L. Cosentino, V. Vlachoudis, F. Mingrone, Cristian Massimi, L. Tassan-Got, Simone Gilardoni, N. Patronis, Sergio Cristallo, A. K. Saxena, Arnaud Ferrari, Alberto Mengoni, I. Ladarescu, Diego Vescovi, V. Furman, T. J. Wright, Claudia Lederer-Woods, M. Caamaño, V. Michalopoulou, E. Mendoza, B. Fernández-Domíngez, A. Oprea, Alberto Ventura, P. M. Milazzo, J. Lerendegui-Marco, S. Amaducci, U. Jiri, L. Caballero, Peter Schillebeeckx, Kathrin Göbel, Deniz Kurtulgil, J. Moreno-Soto, R. Vlastou, E. Berthoumieux, P. J. Davies, Jan Heyse, A. Musumarra, E. Chiaveri, F. Calviño, P. F. Mastinu, C. Rubbia, J. Perkowski, Javier Praena, S. Heinitz, C. Petrone, Q. Ducasse, J. L. Tain, D. Macina, Carlos Guerrero, S. Valenta, R. Garg, Marco Calviani, A. G. Smith, M. Dietz, S. Urlass, V. Babiano-Suarez, A. Manna, A. Gawlik, E. González-Romero, P. Torres-Sánchez, M. Mastromarco, Massimo Barbagallo, Anton Wallner, M. Sabaté-Gilarte, I. Duran, L. A. Damone, B. Thomas, V. Alcayne, E. Dupont, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Ge, Z., Shu, N., Chen, Y., Wang, W., and Zhang, H.
Subjects: Large Hadron Collider, Computer science, Physics, QC1-999, 020209 energy, Nuclear engineering, Nuclear Theory, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Neutron temperature, Nuclear technology, Upgrade, Neutron flux, 0103 physical sciences, n_TOF, CERN, neutron time of flight, 0202 electrical engineering, electronic engineering, information engineering, Neutron cross section, Nuclear astrophysics, Nuclear Physics - Experiment, Neutron, 010306 general physics, Nuclear Experiment
Abstract: International audience; Since the start of its operation in 2001, based on an idea of Prof. Carlo Rubbia [1], the neutron time of-flight facility of CERN, n_TOF, has become one of the most forefront neutron facilities in the world for wide-energy spectrum neutron cross section measurements. Thanks to the combination of excellent neutron energy resolution and high instantaneous neutron flux available in the two experimental areas, the second of which has been constructed in 2014, n_TOF is providing a wealth of new data on neutron-induced reactions of interest for nuclear astrophysics, advanced nuclear technologies and medical applications. The unique features of the facility will continue to be exploited in the future, to perform challenging new measurements addressing the still open issues and long-standing quests in the field of neutron physics. In this document the main characteristics of the n_TOF facility and their relevance for neutron studies in the different areas of research will be outlined, addressing the possible future contribution of n_TOF in the fields of nuclear astrophysics, nuclear technologies and medical applications. In addition, the future perspectives of the facility will be described including the upgrade of the spallation target, the setup of an imaging installation and the construction of a new irradiation area.
Published: 2020
Full Text: View/download PDF

13. Shape coexistence revealed in the $N=Z$ isotope $^{72}$Kr through inelastic scattering

Author: Pieter Doornenbal, G. de Angelis, M. Niikura, T. Arici, M. Zielinska, D. Lubos, E. Sahin, D. T. Doherty, Hiroyoshi Sakurai, J. Gerl, Victor Vaquero, D. G. Jenkins, S. Nagamine, Tohru Motobayashi, Shunji Nishimura, V. H. Phong, Suet Nee Chen, Toshiaki Ando, W. Korten, Alexandre Obertelli, R. Gernhäuser, J. Libert, Hidetada Baba, Jin Wu, Shunpei Koyama, P. J. Davies, J.-P. Delaroche, A. Boso, D. Steppenbeck, R. Taniuchi, Kathrin Wimmer, R. Wadsworth, Berta Rubio, Tomás R. Rodríguez, A. Corsi, Michel Girod, G. Kiss, P. Aguilera, T. Goigoux, T. Saito, Alejandro Algora, L. Sinclair, B. Blank, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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), 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), RIKEN Nishina Center for Accelerator-Based Science, Science and Technology Facilities Council (UK), Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Hungarian Scientific Research Fund, Ministry of Human Capacities (Hungary), 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 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: Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Scattering, Yrast, Hadron, FOS: Physical sciences, State (functional analysis), Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Mean field theory, 0103 physical sciences, Nuclear fusion, Nuclear Experiment (nucl-ex), Atomic physics, 010306 general physics, Ground state, Nuclear Experiment
Abstract: 12 pags., 11 figs., 2 tabs., The N= Z= 36 nucleus Kr has been studied by inelastic scattering at intermediate energies. Two targets, Be and Au, were used to extract the nuclear deformation length, δ, and the reduced E2 transition probability, B(E2). The previously unknown non-yrast 2 and 4 states as well as a new candidate for the octupole 3 state have been observed in the scattering on the Be target and placed in the level scheme based on γ- γ coincidences. The second 2 state was also observed in the scattering on the Au target and the B(E2;22+→01+) value could be determined for the first time. Analyzing the results in terms of a two-band mixing model shows clear evidence for a oblate-prolate shape coexistence and can be explained by a shape change from an oblate ground state to prolate deformed yrast band from the first 2 state. This interpretation is corroborated by beyond mean field calculations using the Gogny D1S interaction., We would like to thank the RIKEN accelerator and BigRIPS teams for providing the high intensity beams. We thank T. Furumoto for providing us with the optical potentials and A. Moro for giving access to an unpublished version of the FRESCO code. This work has been supported by UK STFC under Grant numbers ST/L005727/1 and ST/P003885/1, the Spanish Ministerio de Economía y Competitividad under Grants FPA2011-24553, FPA2014-52823-C2- 1-P, and PGC2018-094583-B-I00, the Program Severo Ochoa (SEV2014-0398), the European Research Council through the ERC Grant No. MINOS-258567, NKFIH (NN128072), and by the ÚNKP-19-4- DE-65 New National Excellence Program of the Ministry of Human Capacities of Hungary. G. K. acknowledges support from the János Bolyai research fellowship of the Hungarian Academy of Sciences. K. W. acknowledges the support from the Spanish Ministerio de Economía y Competitividad RYC-2017-22007.
Published: 2020
Full Text: View/download PDF

14. Monte Carlo simulations and n-p differential scattering data measured with Proton Recoil Telescopes

Author: Z. Eleme, M. Bacak, N. V. Sosnin, S. Urlass, Annamaria Mazzone, Petar Žugec, Alexandru Negret, J. Moreno-Soto, F. Käppeler, P. Sprung, Rugard Dressler, C. Rubbia, P. Torres-Sánchez, A. Tsinganis, E. Dupont, E. Pirovano, V. Michalopoulou, J. Andrzejewski, Luciano Piersanti, E. Mendoza, Nicola Colonna, Q. Ducasse, Vasilis Vlachoudis, A. Mengoni, Peter Schillebeeckx, M. Sabaté-Gilarte, Diego Vescovi, D. Macina, Carlos Guerrero, I. Duran, Simone Gilardoni, R. Garg, S. Valenta, Marco Calviani, J. L. Tain, Emilio Andrea Maugeri, V. Variale, Dimitri Rochman, Arnd R. Junghans, S. Bennett, S. Heinitz, A. G. Smith, M. Dietz, M. Kokkoris, V. Furman, T. J. Wright, M. A. Cortés-Giraldo, D. Cano-Ott, A. Stamatopoulos, C. Petrone, A. Pavlik, V. Babiano-Suarez, R. Vlastou, A. Sekhar, M. Diakaki, E. Berthoumieux, U. Jiri, Claudia Lederer-Woods, Deniz Kurtulgil, C. Domingo-Pardo, E. Chiaveri, P. F. Mastinu, F. Calviño, A. Kimura, B. Fernández-Domíngez, A. Oprea, M. Mastromarco, L. Cosentino, B. Thomas, Y. Kadi, A. Musumarra, Maurizio Busso, Massimo Barbagallo, J. Perkowski, A. Manna, P. J. Woods, Kathrin Göbel, F. Gunsing, Anton Wallner, Ariel Tarifeño-Saldivia, S. J. Lonsdale, N. Patronis, A. K. Saxena, Jan Heyse, F. Ogállar, J. Lerendegui-Marco, Cristian Massimi, Arnaud Ferrari, V. Alcayne, F. Cerutti, L. A. Damone, S. Amaducci, G. Tagliente, D. Ramos Doval, I. Ferro-Gonçalves, I. Ladarescu, G. Cortes, D. Bosnar, F. Mingrone, A. Masi, Y. Kopatch, M. Krtička, A. Casanovas, D. G. Jenkins, Javier Praena, T. Martinez, Ignacio Porras, L. Audouin, G. Vannini, I. Knapova, M. Caamaño, P. Vaz, P. J. Davies, Alberto Ventura, L. Caballero, O. Aberle, M. A. Millán-Callado, A. Gawlik, E. González-Romero, Rene Reifarth, J. M. Quesada, L. Tassan-Got, Sergio Cristallo, E. Jericha, Paolo Finocchiaro, Dorothea Schumann, A. S. Brown, N. Terranova, P. M. Milazzo, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, 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), Ge, Z., Shu, N., Chen, Y., Wang, W., and Zhang, H.
Subjects: Physics, 010308 nuclear & particles physics, Scattering, Fission, QC1-999, Monte Carlo method, Nuclear Theory, n_TOF, proton recoil, Monte Carlo simulations, neutron time of flight, Neutron radiation, Scintillator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, Recoil, Neutron flux, Proton transport, 0103 physical sciences, Nuclear Physics - Experiment, 010306 general physics, Nuclear Experiment
Abstract: The authors wish to thank the National Center of the INFN for Research and Development in Information and Communication Technologies (CNAF) for their computational support., The neutron-induced fission cross section of U-235, a standard at thermal energy and between 0.15 MeV and 200 MeV, plays a crucial role in nuclear technology applications. The long-standing need of improving cross section data above 20 MeV and the lack of experimental data above 200 MeV motivated a new experimental campaign at the n_TOF facility at CERN. The measurement has been performed in 2018 at the experimental area 1 (EAR1), located at 185 m from the neutron-producing target (the experiment is presented by A. Manna et al. in a contribution to this conference). The U-235(n,f) cross section from 20 MeV up to about 1 GeV has been measured relative to the H-1(n,n)H-1 reaction, which is considered the primary reference in this energy region. The neutron flux impinging on the U-235 sample (a key quantity for determining the fission events) has been obtained by detecting recoil protons originating from n-p scattering in a C2H4 sample. Two Proton Recoil Telescopes (PRT), consisting of several layers of solid-state detectors and fast plastic scintillators, have been located at proton scattering angles of 25.07 degrees and 20.32 degrees, out of the neutron beam. The PRTs exploit the Delta E-E technique for particle identification, a basic requirement for the rejection of charged particles from neutron-induced reactions in carbon. Extensive Monte Carlo simulations were performed to characterize proton transport through the different slabs of silicon and scintillation detectors, to optimize the experimental set-up and to deduce the efficiency of the whole PRT detector. In this work we compare measured data collected with the PRTs with a full Monte Carlo simulation based on the Geant-4 toolkit.
Published: 2020
Full Text: View/download PDF

15. First results of the Th-230(n,f) cross section measurements at the CERN n_TOF facility

Author: P. Torres-Sánchez, A. Mengoni, F. Ogállar, M. Mastromarco, Massimo Barbagallo, Anton Wallner, N. V. Sosnin, G. Tagliente, Rugard Dressler, A. Musumarra, Annamaria Mazzone, G. Cortes, I. Ferro-Gonçalves, P. J. Woods, D. Ramos Doval, Y. Kopatch, M. Sabaté-Gilarte, A. Oprea, A. Pavlik, Petar Žugec, P. Sprung, A. Tsinganis, C. Domingo-Pardo, N. Patronis, A. K. Saxena, Simone Gilardoni, L. Audouin, J. L. Tain, Luciano Piersanti, M. A. Cortés-Giraldo, Arnaud Ferrari, Alexandru Negret, E. Chiaveri, Nicola Colonna, F. Käppeler, P. F. Mastinu, A. Casanovas, Vasilis Vlachoudis, I. Ladarescu, E. Pirovano, U. Jiri, A. Kimura, E. Dupont, O. Aberle, S. Urlass, G. Vannini, M. A. Millán-Callado, S. Bennett, V. Variale, V. Babiano-Suarez, Dimitri Rochman, Arnd R. Junghans, J. Andrzejewski, A. Gawlik, B. Femández-Domíngez, A. Stamatopoulos, L. Cosentino, M. Caamaño, R. Vlastou, V. Michalopoulou, Maurizio Busso, Y. Kadi, E. Jericha, E. Berthoumieux, P. J. Davies, Emilio Andrea Maugeri, E. Mendoza, Z. Eleme, Paolo Finocchiaro, L. A. Damone, I. Knapova, Dorothea Schumann, M. Kokkoris, Javier Praena, A. Manna, Peter Schillebeeckx, Claudia Lederer-Woods, Rene Reifarth, P. Vaz, Deniz Kurtulgil, M. Bacak, B. Thomas, J. Moreno-Soto, A. S. Brown, Ariel Tarifeño-Saldivia, S. J. Lonsdale, F. Calviño, Kathrin Göbel, A. Masi, I. Duran, Alberto Ventura, L. Caballero, M. Krtiička, C. Rubbia, E. González-Romero, J. Perkowski, V. Furman, T. J. Wright, F. Cerutti, D. G. Jenkins, S. Heinitz, Jan Heyse, D. Bosnar, C. Petrone, F. Gunsing, Ignacio Porras, V. Alcayne, D. Macina, Carlos Guerrero, Q. Ducasse, D. Cano-Ott, A. Sekhar, M. Diakaki, P. M. Milazzo, J. M. Quesada, T. Martinez, R. Garg, Cristian Massimi, S. Valenta, L. Tassan-Got, Marco Calviani, A. G. Smith, M. Dietz, Sergio Cristallo, F. Mingrone, J. Lerendegui-Marco, S. Amaducci, Diego Vescovi, CEA Cadarache, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, n_TOF, 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), Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, Ge, Z., Shu, N., Chen, Y., Wang, W., and Zhang, H.
Subjects: Physics, Range (particle radiation), n_TOF, 230Th, fission, neutron time of flight, Large Hadron Collider, Isotope, 010308 nuclear & particles physics, Fission, QC1-999, MicroMegas detector, Actinide, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Resonance (particle physics), Nuclear physics, Cross section (physics), 0103 physical sciences, Nuclear Physics - Experiment, 010306 general physics
Abstract: The study of neutron-induced reactions on actinides is of considerable importance for the design of advanced nuclear systems and alternative fuel cycles. Specifically, 230Th is produced from the α-decay of 234U as a byproduct of the 232Th/233U fuel cycle, thus the accurate knowledge of its fission cross section is strongly required. However, few experimental datasets exist in literature with large deviations among them, covering the energy range between 0.2 to 25 MeV. In addition, the study of the 230Th(n,f) cross-section is of great interest in the research on the fission process related to the structure of the fission barriers. Previous measurements have revealed a large resonance at En=715 keV and additional fine structures, but with high discrepancies among the cross-section values of these measurements. This contribution presents preliminary results of the 230Th(n,f) cross-section measurements at the CERN n_TOF facility. The high purity targets of the natural, but very rare isotope 230Th, were produced at JRC-Geel in Belgium. The measurements were performed at both experimental areas (EAR-1 and EAR-2) of the n_TOF facility, covering a very broad energy range from thermal up to at least 100 MeV. The experimental setup was based on Micromegas detectors with the 235U(n,f) and 238U(n,f) reaction cross-sections used as reference.
Published: 2020
Full Text: View/download PDF

16. Half-lives of Sr73 and Y76 and the consequences for the proton dripline

Author: F. Browne, V. Werner, T. Isobe, Shin-Ichiro Nishimura, Hirofumi Watanabe, L. Sinclair, P. J. Davies, Toshiyuki Sumikama, Giuseppe Lorusso, D. Lubos, R. Wadsworth, Naoki Fukuda, Jacek Dobaczewski, Zena Patel, Peter Schury, Shigeru Kubono, P. A. Söderström, H. Baba, Hiroyoshi Sakurai, P. Doornenbal, I. Nishizuka, Z. H. Li, Jin Wu, Jack Henderson, Zhengyu Xu, D. G. Jenkins, D. S. Ahn, Alessandro Pastore, Y. F. Fang, Hiroshi Suzuki, A. Estrade, Stephen Rice, Y. Shimizu, and H. Takeda
Subjects: Physics, Proton, 010308 nuclear & particles physics, Proton decay, Nuclear Theory, 7. Clean energy, 01 natural sciences, Beta decay, Nuclear physics, medicine.anatomical_structure, Fragmentation (mass spectrometry), 0103 physical sciences, medicine, Physics::Accelerator Physics, Density functional theory, Nuclear Experiment, 010306 general physics, Nucleon, Nucleus, Beam (structure)
Abstract: The half-lives of seven nuclei have been determined in the neutron-deficient mass-70 region following their production via fragmentation of a 345 MeV/nucleon Xe124 primary beam on a 740 mg/cm2 Be9 target at the RI Beam Factory, RIKEN. The results include two new (Sr73 and Y76) half-lives and a more precise measurement for the ground-state half-life of Sr74. The new results are discussed with reference to previously published calculations that predict the location of the proton dripline in the light Sr and Y region of the nuclear chart. In addition, differences in the ground-state structure of Rb72 and Y76 are discussed with the aid of density functional theory calculations. These provide a possible explanation for why Rb72 undergoes proton decay while the α-conjugate nucleus Y76 predominantly undergoes β+ decay.
Published: 2019
Full Text: View/download PDF

17. $^{80}$Se(n,$\gamma$) cross-section measurement at CERN n_TOF

Author: I. Knapova, P. Vaz, F. Mingrone, E. Jericha, J. Andrzejewski, Luis Caballero, Paolo Finocchiaro, A. Gawlik, F. Ogállar, V. Vlachoudis, G. Tagliente, D. Ramos Doval, G. Vannini, F. Gunsing, Javier Praena, J. L. Tain, Cristian Massimi, F. Calviño, J. Perkowski, Alberto Ventura, M. Sabaté-Gilarte, Z. Eleme, A. Casanovas, Emilio Andrea Maugeri, E. Mendoza, V. Variale, Dimitri Rochman, Arnd R. Junghans, Rene Reifarth, M. Kokkoris, Y. Kopatch, Carlos Guerrero, L. Cosentino, S. Heinitz, A. Tsinganis, J. Lerendegui-Marco, S. Amaducci, R. Garg, J. M. Quesada, L. Tassan-Got, P. J. Davies, A. Kimura, Diego Vescovi, C. Petrone, Luciano Piersanti, Sergio Cristallo, E. González-Romero, Alfredo Ferrari, Nicola Colonna, E. Chiaveri, G. Cortes, M. A. Cortés-Giraldo, D. Cano-Ott, M. Caamaño, O. Aberle, I. Ferro-Gonçalves, P. J. Woods, E. Dupont, J. Balibrea-Correa, D. Macina, S. Valenta, F. Cerutti, A. Sekhar, M. Diakaki, P. M. Milazzo, Pierfrancesco Mastinu, A. S. Brown, A. Pavlik, N. Patronis, C. Domingo-Pardo, M. Bacak, A. Musumarra, M. A. Millán-Callado, Marco Calviani, P. Schillebeeckx, Mario Barbagallo, B. Fernández-Domíngez, A. G. Smith, D. Schumann, Ignacio Porras, C. Rubbia, Simone Gilardoni, S. Urlass, P. Torres-Sánchez, Alberto Mengoni, I. Ladarescu, A. Oprea, J. Heyse, M. Dietz, M. Mastromarco, U. Jiri, Q. Ducasse, A. Saxena, V. Michalopoulou, K. Göbel, Anton Wallner, S. Bennett, A. Masi, A. Stamatopoulos, T. Wright, J. Moreno-Soto, D. G. Jenkins, I. Duran, Maurizio Busso, R. Vlastou, R. Dressler, Damir Bosnar, Y. Kadi, Ariel Tarifeño-Saldivia, S. J. Lonsdale, L. A. Damone, M. Krtička, T. Martinez, E. Berthoumieux, N. V. Sosnin, Annamaria Mazzone, Petar Žugec, P. Sprung, Alexandru Negret, F. Käppeler, E. Pirovano, V. Babiano-Suarez, A. Manna, V. Furman, B. Thomas, V. Alcayne, L. Audouin, Claudia Lederer-Woods, Deniz Kurtulgil, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, European Research Council (ERC) 681740, Babiano-Suarez V., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Bacak M., Balibrea-Correa J., Barbagallo M., Bennett S., Berthoumieux E., Bosnar D., Brown A.S., Busso M., Caamao M., Caballero L., Calviani M., Calvio F., Cano-Ott D., Casanovas A., Cerutti F., Chiaveri E., Colonna N., Cortes G.P., Cortes-Giraldo M.A., Cosentino L., Cristallo S., Damone L.A., Davies P.J., Diakaki M., Dietz M., Domingo-Pardo C., Dressler R., Ducasse Q., Dupont E., Durn I., Eleme Z., Fernndez-Domingez B., Ferrari A., Ferro-Goncalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Gobel K., Gonzlez-Romero E., Guerrero C., Gunsing F., Heinitz S., Heyse J., Jenkins D.G., Jericha E., Jiri U., Junghans A., Kadi Y., Kappeler F., Kimura A., Knapov I., Kokkoris M., Kopatch Y., Krticka M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lerendegui-Marco J., Lonsdale S.-J., Macina D., Manna A., Martinez T., Masi A., Massimi C., Mastinu P.F., Mastromarco M., Maugeri E., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P.M., Milln-Callado M.A., Mingrone F., Moreno-Soto J., Musumarra A., Negret A., Ogllar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Quesada J.M., Ramos Doval D., Reifarth R., Rochman D., Rubbia C., Sabate-Gilarte M., Saxena A., Schillebeeckx P., Schumann D., Sekhar A., Smith A.G., Sosnin N., Sprung P., Stamatopoulos A., Tagliente G., Tain J.L., Tarifeo-Saldivia A.E., Tassan-Got L., Thomas B., Torres-Snchez P., Tsinganis A., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P.J., Wright T.J., Zugec P., Babiano-Suarez, V., Aberle, O., Alcayne, V., Amaducci, S., Andrzejewski, J., Audouin, L., Bacak, M., Balibrea-Correa, J., Barbagallo, M., Bennett, S., Berthoumieux, E., Bosnar, D., Brown, A. S., Busso, M., Caamao, M., Caballero, L., Calviani, M., Calvio, F., Cano-Ott, D., Casanovas, A., Cerutti, F., Chiaveri, E., Colonna, N., Cortes, G. P., Cortes-Giraldo, M. A., Cosentino, L., Cristallo, S., Damone, L. A., Davies, P. J., Diakaki, M., Dietz, M., Domingo-Pardo, C., Dressler, R., Ducasse, Q., Dupont, E., Durn, I., Eleme, Z., Fernndez-Domingez, B., Ferrari, A., Ferro-Goncalves, I., Finocchiaro, P., Furman, V., Garg, R., Gawlik, A., Gilardoni, S., Gobel, K., Gonzlez-Romero, E., Guerrero, C., Gunsing, F., Heinitz, S., Heyse, J., Jenkins, D. G., Jericha, E., Jiri, U., Junghans, A., Kadi, Y., Kappeler, F., Kimura, A., Knapov, I., Kokkoris, M., Kopatch, Y., Krticka, M., Kurtulgil, D., Ladarescu, I., Lederer-Woods, C., Lerendegui-Marco, J., Lonsdale, S. -J., Macina, D., Manna, A., Martinez, T., Masi, A., Massimi, C., Mastinu, P. F., Mastromarco, M., Maugeri, E., Mazzone, A., Mendoza, E., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Milln-Callado, M. A., Mingrone, F., Moreno-Soto, J., Musumarra, A., Negret, A., Ogllar, F., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., Petrone, C., Piersanti, L., Pirovano, E., Porras, I., Praena, J., Quesada, J. M., Ramos Doval, D., Reifarth, R., Rochman, D., Rubbia, C., Sabate-Gilarte, M., Saxena, A., Schillebeeckx, P., Schumann, D., Sekhar, A., Smith, A. G., Sosnin, N., Sprung, P., Stamatopoulos, A., Tagliente, G., Tain, J. L., Tarifeo-Saldivia, A. E., Tassan-Got, L., Thomas, B., Torres-Snchez, P., Tsinganis, A., Urlass, S., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vescovi, D., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T. J., and Zugec, P.
Subjects: Physics, History, Large Hadron Collider, Isotope, General Physics and Astronomy, 80Se, neutron capture, neutron time of flight, n_TOF, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Computer Science Applications, Education, Nuclear physics, s process, neutron physics, Time of flight, Nucleosynthesis, 0103 physical sciences, Neutron cross section, Radiative transfer, Nuclear Physics - Experiment, Slow neutron, 010306 general physics, s-process, 010303 astronomy & astrophysics
Abstract: Radiative neutron capture cross section measurements are of fundamental importance for the study of the slow neutron capture (s-) process of nucleosynthesis. This mechanism is responsible for the formation of most elements heavier than iron in the Universe. Particularly relevant are branching nuclei along the s-process path, which are sensitive to the physical conditions of the stellar environment. One such example is the branching at 79Se (3.27 × 105 y), which shows a thermally dependent β-decay rate. However, an astrophysically consistent interpretation requires also the knowledge of the closest neighbour isotopes involved. In particular, the 80Se(n,γ) cross section directly affects the stellar yield of the “cold” branch leading to the formation of the s-only 82Kr. Experimentally, there exists only one previous measurement on 80Se using the time of flight (TOF) technique. However, the latter suffers from some limitations that are described in this presentation. These drawbacks have been significantly improved in a recent measurement at CERN n TOF. This contribution presents a summary of the latter measurement and the status of the data analysis.
Published: 2019
Full Text: View/download PDF

18. Pairing properties of the double- β emitter Cd116

Author: T. M. Hatfield, S. J. F. Hughes, T. Faestermann, H.-F. Wirth, S. J. Freeman, B. D. Cropper, Ralf Hertenberger, D. K. Sharp, P. J. Davies, and P. T. MacGregor
Subjects: Physics, Isotope, 010308 nuclear & particles physics, Nuclear Theory, Order (ring theory), 01 natural sciences, Matrix (mathematics), Excited state, Pairing, 0103 physical sciences, Quasiparticle, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Ground state
Abstract: The pairing properties of the neutrinoless double-$\beta$ decay candidate $^{116}$Cd have been investigated. Measurements of the two-neutron removal reactions on isotopes of $^{114,116}$Cd have been made in order to identify 0$^+$ strength in the residual nuclei up to $\approx$3 MeV. No significant $L=0$ strength has been found in excited states indicating that the Bardeen-Cooper-Schrieffer (BCS) approximation is a reasonable basis to describe the neutrons in the ground state. This approximation avoids complications in calculations of double-$\beta$ decay matrix elements that use the quasiparticle random-phase approximation (QRPA) techniques. However this is not the case for the protons, where pair vibrations are prevalent and the BCS approximation is no longer valid, complicating the use of traditional QRPA techniques for this system as a whole.
Published: 2019
Full Text: View/download PDF

19. Properties of γ -decaying isomers in the Sn100 region populated in fragmentation of a Xe124 beam

Author: V. Werner, Torbjörn Bäck, Toshiyuki Sumikama, H. Grawe, K. Moschner, N. Warr, N. Kurz, T. Isobe, Giuseppe Lorusso, M. Górska, M. Dewald, P. J. Davies, F. Ameil, P. Doornenbal, A. Gengelbach, J. Gerl, Hyo Soon Jung, Shin-Ichiro Nishimura, H. Baba, F. Naqvi, E. Gregor, K. Steiger, P. A. Söderström, M. Lewitowicz, Daiki Nishimura, T. Faestermann, D. G. Jenkins, Jan Taprogge, Zhengyu Xu, H. Hotaka, P. Thöle, P. Boutachkov, Ayumi Yagi, H. Watanbe, R. Wadsworth, H. Schaffner, A. Blazhev, G. Häfner, R. Lozeva, Norbert Pietralla, J. Jolie, K. Yoshinaga, I. Kojouharov, E. Merchan, Hiroki Nishibata, Roman Gernhäuser, Shintaro Go, and Y. Zhu
Subjects: Physics, Microsecond, Ion beam, Fragmentation (mass spectrometry), 010308 nuclear & particles physics, 0103 physical sciences, Physics::Accelerator Physics, Atomic physics, Nuclear Experiment, 010306 general physics, 01 natural sciences
Abstract: A systematic study was performed of microsecond γ-decaying isomers around Sn100 produced in a fragmentation reaction of a Xe124 beam at 345 MeV/u at the Radioactive Ion Beam Factory of the RIKEN Nishina Center in Saitama, Japan. Half-lives of isomeric states in that region were remeasured allowing us to improve the currently available experimental information. Reduced transition probabilities were deduced and compared to shell-model calculations in various model spaces. The recently reported low-energy transitions in Rh92 and Ag96 were remeasured with improved precision. Additionally, experimental information on isomeric ratios, including five new ones, were extracted and compared to a previous experimental study and the sharp cutoff model of fragmentation reaction.
Published: 2019
Full Text: View/download PDF

20. The $^{154}$Gd neutron capture cross section measured at the n_TOF facility and its astrophysical implications

Author: F. Ogállar, G. Tagliente, D. Ramos Doval, Z. Eleme, M. Sabaté-Gilarte, Ignacio Porras, A. Casanovas, B. Fernández-Domíngez, A. Oprea, O. Aberle, M. A. Millán-Callado, A. Musumarra, L. Caballero, A. Pavlik, J. Lerendegui-Marco, C. Domingo-Pardo, A. Masi, S. Amaducci, A. S. Brown, R. Vlastou, D. G. Jenkins, E. Berthoumieux, V. Variale, Dimitri Rochman, Rugard Dressler, L. Cosentino, A. Gawlik, Kathrin Göbel, Arnd R. Junghans, A. Kimura, J. Andrzejewski, P. Torres-Sánchez, Claudia Lederer-Woods, E. Dupont, Rene Reifarth, I. Duran, Jan Heyse, Y. Kopatch, S. Bennett, M. A. Cortés-Giraldo, N. V. Sosnin, M. Mastromarco, I. Knapova, F. Cerutti, A. Stamatopoulos, J. M. Quesada, Y. Kadi, V. Vlachoudis, P. Vaz, Massimo Barbagallo, Annamaria Mazzone, L. Tassan-Got, Petar Žugec, A. Tsinganis, Diego Vescovi, Maurizio Busso, Sergio Cristallo, P. Sprung, B. Thomas, F. Mingrone, Anton Wallner, P. M. Milazzo, Simone Gilardoni, Alberto Ventura, Deniz Kurtulgil, Luciano Piersanti, Ariel Tarifeño-Saldivia, S. J. Lonsdale, L. A. Damone, V. Alcayne, U. Jiri, S. Valenta, Nicola Colonna, D. Cano-Ott, E. González-Romero, D. Bosnar, E. Pirovano, V. Michalopoulou, A. Sekhar, M. Diakaki, Marco Calviani, L. Audouin, E. Mendoza, Javier Praena, A. G. Smith, M. Krtička, M. Dietz, Peter Schillebeeckx, E. Jericha, V. Babiano-Suarez, S. Heinitz, F. Calviño, T. Martinez, Paolo Finocchiaro, C. Petrone, J. L. Tain, V. Furman, J. Perkowski, T. J. Wright, Dorothea Schumann, F. Gunsing, Cristian Massimi, E. Chiaveri, J. Moreno-Soto, P. F. Mastinu, S. Urlass, I. Ferro-Gonçalves, C. Rubbia, A. Mengoni, Q. Ducasse, A. Manna, D. Macina, Carlos Guerrero, R. Garg, M. Bacak, Alexandru Negret, F. Käppeler, P. J. Woods, N. Patronis, A. K. Saxena, Arnaud Ferrari, I. Ladarescu, G. Vannini, Emilio Andrea Maugeri, M. Kokkoris, M. Caamaño, P. J. Davies, G. Cortes, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, n_TOF, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, 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), Ge, Z., Shu, N., Chen, Y., Wang, W., and Zhang, H.
Subjects: Physics, Isotope, 010308 nuclear & particles physics, QC1-999, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Neutron temperature, Nuclear physics, Samarium, Neutron capture, Stellar nucleosynthesis, chemistry, n_TOF, 154Gd, neutron capture, neutron time of flight, 0103 physical sciences, Neutron cross section, Nuclear Physics - Experiment, Neutron, Decay chain, Nuclear Experiment, 010303 astronomy & astrophysics
Abstract: The (n, γ) cross sections of the gadolinium isotopes play an important role in the study of the stellar nucleosynthesis. In particular, among the isotopes heavier than Fe, 154Gd together with 152Gd have the peculiarity to be mainly produced by the slow capture process, the so-called s-process, since they are shielded against the β-decay chains from the r-process region by their stable samarium isobars. Such a quasi pure s-process origin makes them crucial for testing the robustness of stellar models in galactic chemical evolution (GCE). According to recent models, the 154Gd and 152Gd abundances are expected to be 15-20% lower than the reference un-branched s-process 150Sm isotope. The close correlation between stellar abundances and neutron capture cross sections prompted for an accurate measurement of 154Gd cross section in order to reduce the uncertainty attributable to nuclear physics input and eventually rule out one of the possible causes of present discrepancies between observation and model predictions. To this end, the neutron capture cross section of 154Gd was measured in a wide neutron energy range (from thermal up to some keV) with high resolution in the first experimental area of the neutron time-of-flight facility n_TOF (EAR1) at CERN. In this contribution, after a brief description of the motivation and of the experimental setup used in the measurement, the preliminary results of the 154Gd neutron capture reaction as well as their astrophysical implications are presented.
Published: 2019
Full Text: View/download PDF

21. Measurement of the energy-differential cross-section of the $^{12}$C(n,p)$^{12}$B and $^{12}$C(n,d)$^{11}$B reactions at the n_TOF facility at CERN

Author: Kathrin Göbel, P. J. Woods, N. Patronis, A. K. Saxena, Jan Heyse, Arnaud Ferrari, O. Aberle, I. Ladarescu, M. A. Millán-Callado, Diego Vescovi, I. Duran, J. Lerendegui-Marco, S. Amaducci, Y. Kadi, M. Sabaté Gilarte, N. V. Sosnin, F. Ogállar, A. Kimura, Emilio Andrea Maugeri, M. Kokkoris, D. Cano-Ott, A. Sekhar, M. Diakaki, Rugard Dressler, I. Ferro-Gonçalves, J. Moreno-Soto, F. Calviño, J. Perkowski, M. Krtička, Claudia Lederer-Woods, Annamaria Mazzone, Petar Žugec, Simone Gilardoni, G. Tagliente, D. Ramos Doval, G. Vannini, A. Musumarra, Alexandru Negret, F. Käppeler, B. Fernández-Domíngez, A. Tsinganis, Luciano Piersanti, T. Martinez, L. A. Damone, P. Sprung, U. Jiri, A. Oprea, Nicola Colonna, V. Michalopoulou, L. Caballero, E. Mendoza, Deniz Kurtulgil, M. Mastromarco, M. Caamaño, V. Babiano-Suarez, J. Andrzejewski, Peter Schillebeeckx, V. Variale, S. Valenta, Dimitri Rochman, Arnd R. Junghans, Massimo Barbagallo, M. Bacak, A. Casanovas, F. Cerutti, V. Vlachoudis, Anton Wallner, M. A. Cortés-Giraldo, Rene Reifarth, Marco Calviani, P. J. Davies, A. Manna, E. Pirovano, G. Cortes, L. Cosentino, A. G. Smith, M. Dietz, J. M. Quesada, L. Tassan-Got, F. Mingrone, Sergio Cristallo, E. Chiaveri, Javier Praena, P. F. Mastinu, S. Urlass, C. Rubbia, V. Furman, T. J. Wright, A. Masi, S. Heinitz, P. Torres-Sánchez, R. Vlastou, C. Petrone, Q. Ducasse, E. Berthoumieux, D. G. Jenkins, D. Bosnar, S. Bennett, A. Stamatopoulos, Z. Eleme, D. Macina, Carlos Guerrero, R. Garg, J. L. Tain, A. Pavlik, C. Domingo-Pardo, L. Audouin, E. Jericha, Paolo Finocchiaro, Dorothea Schumann, A. S. Brown, P. M. Milazzo, Y. Kopatch, F. Gunsing, E. Dupont, I. Knapova, Cristian Massimi, P. Vaz, B. Thomas, V. Alcayne, Alberto Ventura, Maurizio Busso, Ariel Tarifeño-Saldivia, S. J. Lonsdale, Ignacio Porras, A. Mengoni, A. Gawlik, E. González-Romero, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, Ge, Z., Shu, N., Chen, Y., Wang, W., Zhang, H., 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: Physics, Scattering cross-section, Nuclear reaction, Large Hadron Collider, Silicon, 010308 nuclear & particles physics, QC1-999, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Neutron temperature, Nuclear physics, chemistry, 0103 physical sciences, Nuclear Physics - Experiment, Graphite, 010306 general physics, n_TOF, 12C(n, p), 12C(n, d), neutron time of flight, Energy (signal processing)
Abstract: Although the 12C(n,p)12B and 12C(n,d)11B reactions are of interest in several fields of basic and applied Nuclear Physics the present knowledge of these two cross-sections is far from being accurate and reliable, with both evaluations and data showing sizable discrepancies. As part of the challenging n_TOF program on (n,cp) nuclear reactions study, the energy differential cross-sections of the 12C(n,p)12B and 12C(n,d)11 B reactions have been measured at CERN from the reaction thresholds up to 30 MeV neutron energy. Both measurements have been recently performed at the long flight-path (185 m) experimental area of the n_TOF facility at CERN using a pure (99.95%) rigid graphite target and two silicon telescopes. In this paper an overview of the experiment is presented together with a few preliminary results.
Published: 2019
Full Text: View/download PDF

22. Neutron capture measurement at the n TOF facility of the 204Tl and 205Tl s-process branching points

Author: Luis Caballero, V. Michalopoulou, S. Urlass, Maurizio Busso, I. Duran, A. Masi, E. Mendoza, D. Macina, Carlos Guerrero, R. Garg, A. S. Brown, A. Musumarra, Claudia Lederer-Woods, D. G. Jenkins, G. Cortes, Peter Schillebeeckx, Ariel Tarifeño-Saldivia, S. J. Lonsdale, Emilio Andrea Maugeri, U Koester, Deniz Kurtulgil, E. Dupont, I. Ferro-Gonçalves, M. Kokkoris, A. Pavlik, C. Domingo-Pardo, Ignacio Porras, L. Cosentino, A. Kimura, B. Fernández-Domíngez, P. M. Milazzo, M. Mastromarco, F. Mingrone, M. A. Cortés-Giraldo, D. Bosnar, Y. Kopatch, P. J. Woods, G. Vannini, S. Bennett, J Balibrea, J. Lerendegui-Marco, J. Andrzejewski, Massimo Barbagallo, S. Amaducci, A. Stamatopoulos, F. Ogállar, N. Patronis, A. K. Saxena, A. Oprea, M. Caamaño, E. Jericha, I. Knapova, Paolo Finocchiaro, Anton Wallner, Z. Eleme, Arnaud Ferrari, G. Tagliente, V. Vlachoudis, D. Ramos Doval, B. Thomas, P. Vaz, Dorothea Schumann, Alberto Mengoni, I. Ladarescu, Alberto Ventura, L. A. Damone, P. J. Davies, O. Aberle, V. Variale, Dimitri Rochman, Arnd R. Junghans, M. A. Millán-Callado, A. Casanovas, V. Alcayne, Rene Reifarth, A. Gawlik, S. Heinitz, C. Petrone, F. Gunsing, Diego Vescovi, J. M. Quesada, L. Tassan-Got, Cristian Massimi, Y. Kadi, E. González-Romero, Sergio Cristallo, S. Valenta, Marco Calviani, A. G. Smith, P. Torres-Sánchez, M. Dietz, M. Sabaté-Gilarte, J. Moreno-Soto, D. Cano-Ott, A. Sekhar, M. Diakaki, M. Krtička, T. Martinez, E. Chiaveri, P. F. Mastinu, Kathrin Göbel, Jan Heyse, L. Audouin, M. Bacak, Rugard Dressler, A. Tsinganis, Luciano Piersanti, Nicola Colonna, N. V. Sosnin, Annamaria Mazzone, Petar Žugec, P. Sprung, E. Pirovano, R. Vlastou, E. Berthoumieux, V. Furman, T. J. Wright, Simone Gilardoni, U. Jiri, F. Cerutti, F. Calviño, J. Perkowski, Javier Praena, Alexandru Negret, F. Käppeler, V. Babiano-Suarez, A. Manna, J. L. Tain, C. Rubbia, Q. Ducasse, Casanovas, A., Tarifeo-Saldivia, A. E., Domingo-Pardo, C., Calvio, F., Maugeri, E., Guerrero, C., Lerendegui-Marco, J., Dressler, R., Heinitz, S., Schumann, D., Tain, J. L., Quesada, J. M., Aberle, O., Alcayne, V., Amaducci, S., Andrzejewski, J., Audouin, L., Babiano-Suarez, V., Bacak, M., Balibrea, J., Barbagallo, M., Bennett, S., Berthoumieux, E., Bosnar, D., Brown, A. S., Busso, M., Caamao, M., Caballero, L., Calviani, M., Cano-Ott, D., Cerutti, F., Chiaveri, E., Colonna, N., Cortes, G. P., Cortes-Giraldo, M. A., Cosentino, L., Cristallo, S., Damone, L. A., Davies, P. J., Diakaki, M., Dietz, M., Ducasse, Q., Dupont, E., Durn, I., Eleme, Z., Fernndez-Domingez, B., Ferrari, A., Ferro-Goncalves, I., Finocchiaro, P., Furman, V., Garg, R., Gawlik, A., Gilardoni, S., Gobel, K., Gonzlez-Romero, E., Gunsing, F., Heyse, J., Jenkins, D. G., Jericha, E., Jiri, U., Junghans, A., Kadi, Y., Kappeler, F., Kimura, A., Knapov, I., Kokkoris, M., Kopatch, Y., Krticka, M., Kurtulgil, D., Ladarescu, I., Lederer-Woods, C., Lonsdale, S. -J., Macina, D., Manna, A., Martinez, T., Masi, A., Massimi, C., Mastinu, P. F., Mastromarco, M., Mazzone, A., Mendoza, E., Mengoni, A., Michalopoulou, V., Milazzo, P. M., Milln-Callado, M. A., Mingrone, F., Moreno-Soto, J., Musumarra, A., Negret, A., Ogllar, F., Oprea, A., Patronis, N., Pavlik, A., Perkowski, J., Petrone, C., Piersanti, L., Pirovano, E., Porras, I., Praena, J., Ramos Doval, D., Reifarth, R., Rochman, D., Rubbia, C., Sabate-Gilarte, M., Saxena, A., Schillebeeckx, P., Sekhar, A., Smith, A. G., Sosnin, N., Sprung, P., Stamatopoulos, A., Tagliente, G., Tassan-Got, L., Thomas, B., Torres-Snchez, P., Tsinganis, A., Urlass, S., Valenta, S., Vannini, G., Variale, V., Vaz, P., Ventura, A., Vescovi, D., Vlachoudis, V., Vlastou, R., Wallner, A., Woods, P. J., Wright, T. J., Zugec, P., Koester, U., 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 de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Laue-Langevin (ILL), 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), ILL, Casanovas A., Tarifeo-Saldivia A.E., Domingo-Pardo C., Calvio F., Maugeri E., Guerrero C., Lerendegui-Marco J., Dressler R., Heinitz S., Schumann D., Tain J.L., Quesada J.M., Aberle O., Alcayne V., Amaducci S., Andrzejewski J., Audouin L., Babiano-Suarez V., Bacak M., Balibrea J., Barbagallo M., Bennett S., Berthoumieux E., Bosnar D., Brown A.S., Busso M., Caamao M., Caballero L., Calviani M., Cano-Ott D., Cerutti F., Chiaveri E., Colonna N., Cortes G.P., Cortes-Giraldo M.A., Cosentino L., Cristallo S., Damone L.A., Davies P.J., Diakaki M., Dietz M., Ducasse Q., Dupont E., Durn I., Eleme Z., Fernndez-Domingez B., Ferrari A., Ferro-Goncalves I., Finocchiaro P., Furman V., Garg R., Gawlik A., Gilardoni S., Gobel K., Gonzlez-Romero E., Gunsing F., Heyse J., Jenkins D.G., Jericha E., Jiri U., Junghans A., Kadi Y., Kappeler F., Kimura A., Knapov I., Kokkoris M., Kopatch Y., Krticka M., Kurtulgil D., Ladarescu I., Lederer-Woods C., Lonsdale S.-J., Macina D., Manna A., Martinez T., Masi A., Massimi C., Mastinu P.F., Mastromarco M., Mazzone A., Mendoza E., Mengoni A., Michalopoulou V., Milazzo P.M., Milln-Callado M.A., Mingrone F., Moreno-Soto J., Musumarra A., Negret A., Ogllar F., Oprea A., Patronis N., Pavlik A., Perkowski J., Petrone C., Piersanti L., Pirovano E., Porras I., Praena J., Ramos Doval D., Reifarth R., Rochman D., Rubbia C., Sabate-Gilarte M., Saxena A., Schillebeeckx P., Sekhar A., Smith A.G., Sosnin N., Sprung P., Stamatopoulos A., Tagliente G., Tassan-Got L., Thomas B., Torres-Snchez P., Tsinganis A., Urlass S., Valenta S., Vannini G., Variale V., Vaz P., Ventura A., Vescovi D., Vlachoudis V., Vlastou R., Wallner A., Woods P.J., Wright T.J., Zugec P., and Koester U.
Subjects: History, Electron density, Nuclear Theory, General Physics and Astronomy, Natural abundance, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010502 geochemistry & geophysics, 01 natural sciences, Education, Nuclear physics, Nucleosynthesis, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, ddc:530, Nuclear Physics - Experiment, Nuclear Experiment, 010306 general physics, neutron physics, n_TOF, s process nucleosynthesis, 0105 earth and related environmental sciences, Physics, Isotope, Nuclear data, 204Tl, 205Tl, neutron capture, neutron time of flight, n_TOF, Computer Science Applications, Neutron capture, Isotopes of lead, s-process
Abstract: Neutron capture cross sections are one of the fundamental nuclear data in the study of the s (slow) process of nucleosynthesis. More interestingly, the competition between the capture and the decay rates in some unstable nuclei determines the local isotopic abundance pattern. Since decay rates are often sensible to temperature and electron density, the study of the nuclear properties of these nuclei can provide valuable constraints to the physical magnitudes of the nucleosynthesis stellar environment. Here we report on the capture cross section measurement of two thallium isotopes, 204Tl and 205Tl performed by the time-of-flight technique at the n TOF facility at CERN. At some particular stellar s-process environments, the decay of both nuclei is strongly enhanced, and determines decisively the abundance of two s-only isotopes of lead, 204Pb and 205Pb. The latter, as a long-lived radioactive nucleus, has potential use as a chronometer of the last s-process events that contributed to final solar isotopic abundances.
Published: 2020
Full Text: View/download PDF

23. Discovery of $^{68}$Br in secondary reactions of radioactive beams

Author: Ryo Taniuchi, A. Corsi, W. Korten, G. de Angelis, P. J. Davies, A. Obertelli, Kathrin Wimmer, Hiroyoshi Sakurai, T. Motobayashi, R. Wadsworth, Berta Rubio, M. Zielińska, T. Saito, Megumi Niikura, E. Sahin, D. T. Doherty, H. Baba, Shoko Koyama, P. Aguilera, D. Lubos, S. Nagamine, P. Doornenbal, D. G. Jenkins, B. Blank, T. Arici, J. Gerl, A. Boso, Alejandro Algora, David Steppenbeck, Toshiaki Ando, L. Sinclair, Si-Ge Chen, Roman Gernhäuser, 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 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), 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), Ministerio de Economía y Competitividad (España), 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 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 and High Energy Physics, Direct reaction, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Particle identification, Nuclear physics, Direct production, Fragmentation (mass spectrometry), 0103 physical sciences, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, Spectrometer, Isotope, 010308 nuclear & particles physics, Projectile, lcsh:QC1-999, Physics::Accelerator Physics, New isotope, Radioactive beams, Nucleon, lcsh:Physics
Abstract: The proton-rich isotope 68Br was discovered in secondary fragmentation reactions of fast radioactive beams. Proton-rich secondary beams of 70,71,72Kr and 70Br, produced at the RIKEN Nishina Center and identified by the BigRIPS fragment separator, impinged on a secondary 9Be target. Unambiguous particle identification behind the secondary target was achieved with the ZeroDegree spectrometer. Based on the expected direct production cross sections from neighboring isotopes, the lifetime of the ground or long-lived isomeric state of 68Br was estimated. The results suggest that secondary fragmentation reactions, where relatively few nucleons are removed from the projectile, offer an alternative way to search for new isotopes, as these reactions populate preferentially low-lying states., Comment: Phys. Lett. B accepted
Published: 2019
Full Text: View/download PDF

24. Fission program at n_TOF

Author: A. Musumarra, E. Dupont, J. Lerendegui-Marco, S. Amaducci, M. A. Cortés-Giraldo, I. Ferro-Gonçalves, J. Moreno-Soto, B. Fernández-Domíngez, A. Oprea, A. Kimura, T. Martinez, A. Mengoni, Z. Eleme, M. Bacak, J. Andrzejewski, Emilio Andrea Maugeri, D. Cano-Ott, A. Sekhar, M. Diakaki, A. Pavlik, M. Kokkoris, Alexandru Negret, Diego Vescovi, Kathrin Göbel, C. Domingo-Pardo, I. Duran, C. Rubbia, F. Käppeler, L. Caballero, M. Sabaté-Gilarte, Simone Gilardoni, V. Variale, Dimitri Rochman, Arnd R. Junghans, Rugard Dressler, Jan Heyse, G. Cortes, Maurizio Busso, A. Masi, A. Gawlik, Y. Kopatch, V. Babiano-Suarez, Q. Ducasse, Ariel Tarifeño-Saldivia, S. J. Lonsdale, D. G. Jenkins, L. Cosentino, A. Tsinganis, Luciano Piersanti, Nicola Colonna, Ignacio Porras, Vasilis Vlachoudis, J. L. Tain, E. Chiaveri, U. Jiri, P. F. Mastinu, V. Furman, T. J. Wright, B. Thomas, D. Bosnar, Y. Kadi, Rene Reifarth, G. Vannini, V. Alcayne, E. González-Romero, L. A. Damone, O. Aberle, D. Macina, M. Caamaño, Carlos Guerrero, N. V. Sosnin, A. Manna, M. A. Millán-Callado, Javier Praena, R. Garg, M. Krticˇka, Annamaria Mazzone, Petar Žugec, S. Valenta, F. Ogállar, P. J. Davies, F. Mingrone, S. Bennett, G. Tagliente, P. Sprung, Marco Calviani, D. Ramos Doval, A. Stamatopoulos, J. M. Quesada, F. Gunsing, L. Tassan-Got, P. Torres-Sánchez, A. G. Smith, S. Urlass, M. Mastromarco, M. Dietz, A. Casanovas, Cristian Massimi, F. Cerutti, Sergio Cristallo, Massimo Barbagallo, Claudia Lederer-Woods, Anton Wallner, E. Pirovano, Deniz Kurtulgil, I. Knapova, S. Heinitz, P. Vaz, C. Petrone, R. Vlastou, E. Berthoumieux, F. Calviño, J. Perkowski, Alberto Ventura, P. J. Woods, N. Patronis, A. K. Saxena, Arnaud Ferrari, I. Ladarescu, L. Audouin, V. Michalopoulou, E. Mendoza, Peter Schillebeeckx, A. S. Brown, P. M. Milazzo, Paolo Finocchiaro, Dorothea Schumann, Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. Doctorat en Enginyeria Nuclear i de les Radiacions Ionitzants, Universitat Politècnica de Catalunya. ANT - Advanced Nuclear Technologies Research Group, 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), Université Paris-Sud - Paris 11 (UP11), Université Paris-Saclay, 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, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, 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: Nuclear reaction, Fission, QC1-999, Nuclear Theory, Nuclear physics, 01 natural sciences, Plutonium-240, 0103 physical sciences, Plutonium-242, CERN, Neutron, n_TOF, Neutron captures, n_TOF, Fission, r-process, 010306 general physics, Nuclear Experiment, Physics, [PHYS]Physics [physics], Energies::Energia nuclear [Àrees temàtiques de la UPC], Neutrons, Física [Àrees temàtiques de la UPC], Cross section, Neutron captures, 010308 nuclear & particles physics, r-process, Neutron radiation, Neutron capture, n_TOF, fission program, cross section measurements, Física nuclear, Other
Abstract: Since its start in 2001 the n_TOF collaboration developed a measurement program on fission, in view of advanced fuels in new generation reactors. A special effort was made on measurement of cross sections of actinides, exploiting the peculiarity of the n_TOF neutron beam which spans a huge energy domain, from the thermal region up to GeV. Moreover fission fragment angular distributions have also been measured. An overview of the cross section results achieved with different detectors is presented, including a discussion of the 237Np case where discrepancies showed up between different detector systems. The results on the anisotropy of the fission fragments and its implication on the mechanism of neutron absorption, and in applications, are also shown.
Published: 2019
Full Text: View/download PDF

25. Confirming band assignments in $^{167}$ytterbium with gamma-gamma-electron triple-coincidence spectroscopy

Author: A. K. Mistry, Philippos Papadakis, S. Juutinen, Pauli Peura, A. Lopez-Martens, Daniel Cox, Andrej Herzan, Juha Sorri, Juha Uusitalo, Paul Greenlees, Ulrika Jakobsson, C. Scholey, James Smallcombe, R-D Herzberg, Panu Ruotsalainen, K. Hauschild, T. Grahn, Sami Rinta-Antila, Steffen Ketelhut, P. A. Butler, Jan Sarén, Peter M. Jones, D. G. Jenkins, Mikael Sandzelius, Paivi Nieminen, E. Parr, R. Julin, C. J. Barton, P. J. Davies, Matti Leino, Janne Pakarinen, L.-L. Andersson, P. Rahkila, 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: Physics, Ytterbium, Nuclear and High Energy Physics, Spectrometer, Silicon, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Hadron, chemistry.chemical_element, Germanium, Electron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, chemistry, 0103 physical sciences, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Atomic physics, 010306 general physics, Spectroscopy, Spin (physics), Nuclear Experiment
Abstract: International audience; Multipolarity measurements are presented for transitions in the deformed odd-mass nucleus$^{167}$ Yb in support of tentative spin assignments and level interpretations based upon the cranked-Nilsson model. Internal-conversion coefficients were measured with the SAGE (Silicon And GErmanium) spectrometer confirming several E2 transition assignments. The array of high-purity germanium detectors enabled the recording of high-multiplicity events from which $\gamma\gamma\gamma$ and $\gamma\gamma e^{-}$ data sets were extracted and the technique of high-fold $\gamma$ -ray gating was demonstrated to cleanly isolate transitions of interest.
Published: 2019
Full Text: View/download PDF

26. Corrigendum to 'Fission fragment atomic number measurements using bragg detectors' [Nucl. Instrum. Methods Phys. Res. A 957 (2020) 163397]

Author: R.L. Kennedy-Reid, Ulli Köster, P. J. Davies, B. S. Nara Singh, A. G. Smith, T. J. Wright, N. V. Sosnin, and Aurelien Blanc
Subjects: Physics, Nuclear physics, Nuclear and High Energy Physics, Fission, Fragment (computer graphics), Detector, Atomic number, Instrumentation
Published: 2020
Full Text: View/download PDF

27. Study of the photon strength functions and level density in the gamma decay of the n + $^{234}U$ reaction

Author: J. Moreno-Soto, W Dridi, L. Persanti, G. Cortes, S. Urlass, A. Musumarra, J. Andrzejewski, O Litaize, A. Kimura, Javier Praena, M. Bacak, S. Valenta, O. Aberle, A. Oprea, Diego Vescovi, Marco Calviani, Maurizio Busso, A. G. Smith, D. Macina, Carlos Guerrero, A Chebboubi, V. Variale, Dimitri Rochman, Arnd R. Junghans, M. Dietz, S. Heinitz, G. Vannini, Ariel Tarifeño-Saldivia, S. J. Lonsdale, A. Gawlik, C. Petrone, Thomas Rauscher, L. A. Damone, E. Chiaveri, Rugard Dressler, P. F. Mastinu, A. Pavlik, F. Cerutti, M. Sabaté-Gilarte, N. V. Sosnin, C. Domingo-Pardo, Annamaria Mazzone, L. Caballero-Ontanaya, A. Tsinganis, M. Caamaño, Claudia Lederer-Woods, S. Bennett, I. Duran, F. Gunsing, M. Krtiˇcka, E. González-Romero, Petar Žugec, O. Serot, P. Sprung, A. Stamatopoulos, Nicola Colonna, Ignacio Porras, Deniz Kurtulgil, A. Mengoni, Kathrin Göbel, E. Dupont, Vasilis Vlachoudis, P. J. Davies, Simone Gilardoni, D. Ramos-Doval, Cristian Massimi, Z. Eleme, Y. Kadi, S. Simone, M. Mastromarco, V. Alcayne, Massimo Barbagallo, E. Pirovano, Jan Heyse, Anton Wallner, D. Cano-Ott, A. Sekhar, M. Diakaki, T. Martinez, J. Ulrich, R. Vlastou, E. Berthoumieux, Y. Kopatch, V. Furman, T. J. Wright, F. Mingrone, I. F. Gonçalves, I. Knapova, F. Calviño, P. Vaz, J. Perkowski, M. A. Cortés-Giraldo, L. Audouin, Alberto Ventura, D. Bosnar, Th. Benedikt, Alexandru Negret, B. Fernández-Domínguez, F. Käppeler, V. Babiano-Suarez, L. Cosentino, A. Manna, F. Ogállar, A. Masi, D. G. Jenkins, G. Tagliente, A. Casanovas, Paolo Finocchiaro, Dorothea Schumann, A. S. Brown, V. Bécares, P. M. Milazzo, Rene Reifarth, J. M. Quesada, L. Tassan-Got, Sergio Cristallo, V. Michalopoulou, E. Mendoza, Peter Schillebeeckx, Emilio Andrea Maugeri, M. Kokkoris, P. J. Woods, N. Patronis, A. K. Saxena, Arnaud Ferrari, I. Ladarescu, J. Billowes, Q. Ducasse, J. L. Tain, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université Paris-Saclay, CEA Cadarache, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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), Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11), n_TOF, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, 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), Serot, O., and Chebboubi, A.
Subjects: neutron captures, Physics, [PHYS]Physics [physics], Photon, Large Hadron Collider, actinides, 010308 nuclear & particles physics, QC1-999, Astrophysics::High Energy Astrophysical Phenomena, Radiative capture, Gamma ray, neutron captures, n_TOF, actinides, Actinide, n_TOF, photon strengts, level density, 234U, 01 natural sciences, Spectral line, Nuclear physics, 13. Climate action, 0103 physical sciences, n_TOF, Other, Multiplicity (chemistry), 010306 general physics, Nuclear Experiment
Abstract: The accurate calculations of neutron-induced reaction cross sections are relevant for many nuclear applications. The photon strength functions and nuclear level densities are essential inputs for such calculations. These quantities for 235U are studied using the measurement of the gamma de-excitation cascades in radiative capture on 234U with the Total Absorption Calorimeter at n_TOF at CERN. This segmented 4π gamma calorimeter is designed to detect gamma rays emitted from the nucleus with high efficiency. This experiment provides information on gamma multiplicity and gamma spectra that can be compared with numerical simulations. The code diceboxc is used to simulate the gamma cascades while geant4 is used for the simulation of the interaction of these gammas with the TAC materials. Available models and their parameters are being tested using the present data. Some preliminary results of this ongoing study are presented and discussed.
Published: 2018
Full Text: View/download PDF

28. Properties of $\gamma $-decaying Isomers in the $^{100}$Sn Region Revisited

Author: Giuseppe Lorusso, M. Dewald, Hiroki Nishibata, H. Baba, E. Gregor, Shin-Ichiro Nishimura, A. Gengelbach, P. Thöle, H. Schaffner, V. Werner, T. Isobe, A. Blazhev, J. Gerl, F. Naqvi, P. J. Davies, Shintaro Go, Y. Zhu, Ayumi Yagi, K. Moschner, Toshiyuki Sumikama, Torbjörn Bäck, J. Jolie, T. Faestermann, D. G. Jenkins, P. Doornenbal, E. Merchan, M. Górska, M. Lewitowicz, N. Warr, Roman Gernhäuser, K. Steiger, Jan Taprogge, Zhengyu Xu, F. Ameil, H. Hotaka, K. Yoshinaga, I. Kojouharov, H. Grawe, N. Kurz, P. A. Söderström, Norbert Pietralla, Hirofumi Watanabe, R. Wadsworth, Daiki Nishimura, G. Haefner, P. Boutachkov, Hyo Soon Jung, 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), 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), RIKEN Nishina Center for Accelerator-Based Science, University of Tokyo, Federal Ministry of Education and Research (Germany), Department of Energy (US), Bonn-Cologne Graduate School of Physics and Astronomy, and SCOAP
Subjects: Physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Nuclear Theory, Astrophysics::Instrumentation and Methods for Astrophysics, Nuclear structure, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Nuclear physics, medicine.anatomical_structure, 0103 physical sciences, medicine, Nuclear Experiment, 010306 general physics, 010303 astronomy & astrophysics, Nucleus
Abstract: 7 pags., 4 figs. -- Presented at the Zakopane Conference on Nuclear Physics “Extremes of the Nuclear Landscape”, Zakopane, Poland, August 26–September 2, 2018. -- Open Access funded by Creative Commons Atribution Licence 4.0, The study of nuclei in the region around the N = Z doubly-magic nucleus 100Sn has been of long standing interest for the nuclear structure and nuclear astrophysics. Recently, Park et al. have reported on properties of γ-decaying isomers and isomeric ratios in the vicinity of 100Sn. That experiment was performed at the Radioactive Ion Beam Factory (RIBF) of the RIKEN Nishina Center in Japan as a part of the EURICA campaign. Neutron-deficient nuclei were produced in a fragmentation reaction of a 124Xe primary beam on a 9Be target at an energy of 345 MeV/A. Secondary ions were separated and identified in the BigRIPS fragment separator and implanted in the silicon detector array WAS3ABi. The data presented here were obtained in another experiment performed at the RIBF using the same reaction but slightly different separator settings. New results of ratios of isomeric population and half-lives of γ-decaying isomers populated in the experiment are presented., This work was carried out at the RIBF operated by the RIKEN Nishina Center, RIKEN and CNS, University of Tokyo. The authors acknowledge the EUROBALL Owners Committee for the loan of germanium detectors and the PreSpec Collaboration for the readout electronics of cluster detectors. This work was partly supported by the German BMBF under contract No. 05P12PKFNE and No. 05P15PKFNA and by the U.S. DOE under grant No. DE-FG02-91ER-40609. G.H. is supported by the Bonn–Cologne Graduate School of Physics and Astronomy.
Published: 2018
Full Text: View/download PDF

29. Shape coexistence and isospin symmetry in $A=70$ nuclei: Spectroscopy of the $T_z = -1$ nucleus $^{70}$Kr

Author: Kathrin Wimmer, Ryo Taniuchi, Roman Gernhäuser, P. Aguilera, W. Korten, Toshiaki Ando, T. Saito, Si-Ge Chen, H. Baba, David Steppenbeck, D. G. Jenkins, R. Wadsworth, Berta Rubio, Shoko Koyama, L. Sinclair, Andrea Corsi, E. Sahin, D. T. Doherty, A. Boso, S. Nagamine, J. Gerl, T. Arici, B. Blank, P. Doornenbal, Megumi Niikura, M. Zielińska, Alejandro Algora, P. J. Davies, G. de Angelis, A. Obertelli, D. Lubos, Hiroyoshi Sakurai, T. Motobayashi, 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 d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), 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), 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 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)
Subjects: Nuclear and High Energy Physics, Mirror symmetry, FOS: Physical sciences, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Gamma-ray spectroscopy, Radioactive beams, Shape coexistence, 0103 physical sciences, medicine, ddc:530, Gamma spectroscopy, Nuclear Experiment (nucl-ex), 010306 general physics, Spectroscopy, Nuclear Experiment, Physics, 010308 nuclear & particles physics, Parity (physics), lcsh:QC1-999, medicine.anatomical_structure, Excited state, Isospin, Physics::Accelerator Physics, Atomic physics, Nucleus, lcsh:Physics
Abstract: Excited states in the $T_z=-1$ nucleus $^{70}$Kr have been populated using inelastic scattering of a radioactive $^{70}$Kr beam as well as one- and two-neutron removal reactions from $^{71,72}$Kr at intermediate beam energies. The level scheme of $^{70}$Kr was constructed from the observed $\gamma$-ray transitions and coincidences. Tentative spin and parity assignments were made based on comparison with the mirror nucleus $^{70}$Se. A second $2^+$ state and a candidate for the corresponding $4^+_2$ state suggest shape coexistence in $^{70}$Kr., Comment: accepted Phys. Lett. B
Published: 2018
Full Text: View/download PDF

30. Determination of absolute internal conversion coefficients using the SAGE spectrometer

Author: Juha Sorri, C. J. Barton, D. G. Jenkins, Mikael Sandzelius, P. J. Davies, Juha Uusitalo, R-D Herzberg, Philippos Papadakis, Paul Greenlees, Joonas Konki, Kalle Auranen, Daniel Cox, Panu Rahkila, Jari Partanen, Janne Pakarinen, and James Smallcombe
Subjects: Nuclear and High Energy Physics, electron spectroscopy, 01 natural sciences, Particle detector, Internal conversion, Optics, 0103 physical sciences, 010306 general physics, Internal conversion coefficient, Instrumentation, silicon detector, background subtraction, energy reconstruction, Physics, Background subtraction, Spectrometer, ta114, 010308 nuclear & particles physics, business.industry, 3. Good health, Computational physics, Semiconductor detector, Measuring instrument, business, Radioactive decay, internal conversion coefficient
Abstract: A non-reference based method to determine internal conversion coefficients using the SAGE spectrometer is carried out for transitions in the nuclei of 154 Sm, 152 Sm and 166 Yb. The Normalised-Peak-to-Gamma method is in general an efficient tool to extract internal conversion coefficients. However, in many cases the required well-known reference transitions are not available. The data analysis steps required to determine absolute internal conversion coefficients with the SAGE spectrometer are presented. In addition, several background suppression methods are introduced and an example of how ancillary detectors can be used to select specific reaction products is given. The results obtained for ground-state band E2 transitions show that the absolute internal conversion coefficients can be extracted using the methods described with a reasonable accuracy. In some cases of less intense transitions only an upper limit for the internal conversion coefficient could be given.
Published: 2016

31. M1 and E2 transition rates from core-excited states in semi-magic 94Ru

Author: V. Modamio, F. Ghazi Moradi, Ulrika Jakobsson, Bo Cederwall, Torbjörn Bäck, H. W. Li, J. J. Valiente-Dobón, M. Siciliano, S. Erturk, István Kuti, Chong Qi, Eiji Ideguchi, D. R. Napoli, C. Michelagnoli, S. S. Ghugre, A. Gottardo, R. Wadsworth, János Timár, R. Raut, Zs. Dombradi, M. Doncel, A. Algora, A. Boso, G. Jaworski, G. de Angelis, P. J. Davies, Zhigang Xiao, D. M. Debenham, H. Al Azri, C. M. Petrache, A. Atac, Eric Clément, Baki Akkuş, F. Recchia, Mikael Sandzelius, A. Gadea, T. Hüyük, A. Ertoprak, M. Palacz, Johan Nyberg, B. M. Nyakó, Ertoprak, A., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden, Department of Physics, Faculty of Science, Istanbul University, Vezneciler/Fatih, Istanbul, 34134, Turkey -- Cederwall, B., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden -- Qi, C., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden -- Doncel, M., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden, Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Jakobsson, U., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden, Department of Chemistry, University of Helsinki, P.O. Box 3, Helsinki, 00014, Finland -- Nyakó, B.M., MTA Atomki, Debrecen, H-4001, Hungary -- Jaworski, G., Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro, I-35020, Italy -- Davies, P., Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom -- de France, G., Grand Accélérateur National d’Ions Lourds (GANIL), CEA/DSM - CNRS/IN2P3, Bd Henri Becquerel, BP 55027, Caen Cedex 5, F-14076, France -- Kuti, I., MTA Atomki, Debrecen, H-4001, Hungary -- Napoli, D.R., Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro, I-35020, Italy -- Wadsworth, R., Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom -- Ghugre, S.S., UGC-DAE Consortium for Scientific Research, Kolkata Centre, Kolkata, 700098, India -- Raut, R., UGC-DAE Consortium for Scientific Research, Kolkata Centre, Kolkata, 700098, India -- Akkus, B., Department of Physics, Faculty of Science, Istanbul University, Vezneciler/Fatih, Istanbul, 34134, Turkey -- Al Azri, H., Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom -- Algora, A., MTA Atomki, Debrecen, H-4001, Hungary, Instituto de Física Corpuscular, CSIC-Universidad de Valencia, Valencia, E-46980, Spain -- de Angelis, G., Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro, I-35020, Italy -- Atac, A., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden -- Bäck, T., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden -- Boso, A., Dipartimento di Fisica e Astronomia, Università di Padova, Padova, Italy -- Clément, E., Grand Accélérateur National d’Ions Lourds (GANIL), CEA/DSM - CNRS/IN2P3, Bd Henri Becquerel, BP 55027, Caen Cedex 5, F-14076, France -- Debenham, D.M., Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom -- Dombrádi, Z., MTA Atomki, Debrecen, H-4001, Hungary -- Ertürk, S., Nigde Omer Halisdemir University, Science and Art Faculty, Department of Physics, Nigde, 51200, Turkey -- Gadea, A., Instituto de Física Corpuscular, CSIC-Universidad de Valencia, Valencia, E-46980, Spain -- Ghazi Moradi, F., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden -- Gottardo, A., Centre de Sciences Nucléaires et Sciences de la Matière, CNRS/IN2P3, Université Paris-Saclay, Orsay, 91405, France -- Hüyük, T., Instituto de Física Corpuscular, CSIC-Universidad de Valencia, Valencia, E-46980, Spain -- Ideguchi, E., Research Center for Nuclear Physics, Osaka University, Osaka, Japan -- Li, H., Department of Physics, Royal Institute of Technology (KTH), Stockholm, SE-10691, Sweden -- Michelagnoli, C., Grand Accélérateur National d’Ions Lourds (GANIL), CEA/DSM - CNRS/IN2P3, Bd Henri Becquerel, BP 55027, Caen Cedex 5, F-14076, France -- Modamio, V., Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro, I-35020, Italy -- Nyberg, J., Department of Physics and Astronomy, Uppsala University, Uppsala, SE-75120, Sweden -- Palacz, M., Heavy Ion Laboratory, University of Warsaw, Pasteura 5A, Warsaw, PL 02-093, Poland -- Petrache, C.M., Centre de Sciences Nucléaires et Sciences de la Matière, CNRS/IN2P3, Université Paris-Saclay, Orsay, 91405, France -- Recchia, F., Dipartimento di Fisica e Astronomia, Università di Padova, Padova, Italy -- Sandzelius, M., University of Jyväskylä, Department of Physics, Jyväskylä, FI-40014, Finland -- Siciliano, M., Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro, I-35020, Italy -- Timár, J., MTA Atomki, Debrecen, H-4001, Hungary -- Valiente-Dobón, J.J., Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro, I-35020, Italy -- Xiao, Z.G., Department of Physics, Tsinghua University, Beijing, 100084, China, 0-Belirlenecek, 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 de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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), 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: Physics, Nuclear reaction, Nuclear and High Energy Physics, Angular momentum, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, Hadron, Elementary particle, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Spectral line, 0-Belirlenecek, Baryon, Excited state, 0103 physical sciences, Atomic physics, 010306 general physics, Nucleon
Abstract: Lifetimes of high-spin states have been measured in the semi-magic (N= 50) nucleus 94Ru. Excited states in 94Ru were populated in the 58Ni(40Ca, 4p)94Ru* fusion-evaporation reaction at the Grand Accélérateur National d’Ions Lourds (GANIL) accelerator complex. DSAM lifetime analysis was performed on the Doppler broadened line shapes in energy spectra obtained from ?-rays emitted while the residual nuclei were slowing down in a thick 6mg/cm^2 metallic 58Ni target. In total eight excited-state lifetimes in the angular momentum range I= (13 - 20) ? have been measured, five of which were determined for the first time. The corresponding B(M1) and B(E2) reduced transition strengths are discussed within the framework of large-scale shell model calculations to study the contribution of different particle-hole configurations, in particular for analyzing contributions from core-excited configurations. © 2018, SIF, Springer-Verlag GmbH Germany, part of Springer Nature., National Brain Research Centre Vetenskapsrådet Göran Gustafssons Stiftelse för Naturvetenskaplig och Medicinsk Forskning Firat University Scientific Research Projects Management Unit Ministerio de Economía y Competitividad Science and Technology Facilities Council, We thank the operators of the GANIL cyclotrons for providing the beam, their cooperation and technical support. We would also like to thank the EXOGAM, DIAMANT and Neutron Wall Collaborations. This work was supported by the Swedish Research Council under Grant Nos. 621-2014-5558, 621-2012-3805, and 621-2013-4323 and the Göran Gustafsson foundation, the Scientific Research Projects Coordination Unit of Istanbul University Project No. 47886 and 48101, the UK STFC under grant number ST/L005727/1, the Spanish Ministerio de Economía y Competitividad under grant FPA2014-52823-C2-1-P and the program Severo Ochoa (SEV-2014-0398), the Polish National Research Centre contracts no. 2013/08/M/ST2 /00257 (LEA COPIGAL) and 2016/22/M/ST2/00269, the Scientific and Technological Council of Turkey (Proj. no. 114F473). BMN, IK, ZD and JT acknowledge the financial support of GINOP-2.3.3-15-2016-00034. IK was supported by National Research, Development and Innovation Office NK-FIH, contract number PD 124717. The computations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC) at PDC, KTH, Stockholm.
Published: 2018
Full Text: View/download PDF

32. Discovery of Rb72 : A Nuclear Sandbank Beyond the Proton Drip Line

Author: Y. F. Fang, Jack Henderson, Hiroyoshi Sakurai, F. Browne, Simon M Rice, Jinguang Wu, Zhengyu Xu, V. Werner, H. Takeda, Z. Patel, Z. H. Li, Y. Shimizu, Shigeru Kubono, H. Baba, DeukSoon Ahn, A. Estrade, P-A Soderstrom, Shin-Ichiro Nishimura, P. Doornenbal, D. Lubos, Tomio Kubo, I. Nishizuka, T. Isobe, Peter Schury, Enrico Maglione, P. J. Davies, Lidia S. Ferreira, Hiroshi Suzuki, D. G. Jenkins, Toshiyuki Sumikama, Giuseppe Lorusso, Naoki Fukuda, L. Sinclair, Naohito Inabe, Hirofumi Watanabe, and R. Wadsworth
Subjects: Physics, Proton, 010308 nuclear & particles physics, Proton decay, SHELL model, General Physics and Astronomy, 01 natural sciences, Atomic mass, 0103 physical sciences, Atomic physics, 010306 general physics, Mirror symmetry, Energy (signal processing), Line (formation)
Abstract: In this Letter, the observation of two previously unknown isotopes is presented for the first time: $^{72}\mathrm{Rb}$ with 14 observed events and $^{77}\mathrm{Zr}$ with one observed event. From the nonobservation of the less proton-rich nucleus $^{73}\mathrm{Rb}$, we derive an upper limit for the ground-state half-life of 81 ns, consistent with the previous upper limit of 30 ns. For $^{72}\mathrm{Rb}$, we have measured a half-life of 103(22) ns. This observation of a relatively long-lived odd-odd nucleus, $^{72}\mathrm{Rb}$, with a less exotic odd-even neighbor, $^{73}\mathrm{Rb}$, being unbound shows the diffuseness of the proton drip line and the possibility of sandbanks to exist beyond it. The $^{72}\mathrm{Rb}$ half-life is consistent with a ${5}^{+}\ensuremath{\rightarrow}5/{2}^{\ensuremath{-}}$ proton decay with an energy of 800--900 keV, in agreement with the atomic mass evaluation proton-separation energy as well as results from the finite-range droplet model and shell model calculations using the GXPF1A interaction. However, we cannot explicitly exclude the possibility of a proton transition between ${9}^{+}(^{72}\mathrm{Rb})\ensuremath{\rightarrow}9/{2}^{+}(^{71}\mathrm{Kr})$ isomeric states with a broken mirror symmetry. These results imply that $^{72}\mathrm{Kr}$ is a strong waiting point in x-ray burst $rp$-process scenarios.
Published: 2017
Full Text: View/download PDF

33. Gamma decay of pygmy states in $^{90,94}$Zr from inelastic scattering of light ions

Author: D. Montanari, L. Morris, Y. D. Fang, M. Spieker, Takeshi Koike, Johann Isaak, P. J. Davies, B. Wasilewska, T. Klaus, Deniz Savran, Shumpei Noji, C. Sullivan, G. Gey, O. Wieland, M. Kumar Raju, J. J. Carroll, G. Steinhilber, S. Zhu, T. H. Hoang, A. Czeszumska, X. K. Zhou, A. Inoue, S. G. Pickstone, N. Ichige, D. G. Jenkins, A. S. Brown, Atsushi Tamii, Nobumichi Kobayashi, Tetsuya Yamamoto, Nori Aoi, N. Blasi, F. Camera, A. Bracco, V. Werner, A. Maj, M. L. Liu, O. H. Jin, Eiji Ideguchi, M. P. Carpenter, C. Iwamoto, Yasuo Yamamoto, H. Fujita, S. Bassauer, M. Krzysiek, M. Ciemala, F. C. L. Crespi, L. M. Donaldson, D. L. Balabanski, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), and Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, History, Scintillation, Spectrometer, 010308 nuclear & particles physics, Gamma ray, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Resonance (particle physics), Computer Science Applications, Education, Ion, Nuclear physics, Dipole, 0103 physical sciences, ddc:530, 010306 general physics, Hpge detector, Nuclear Experiment
Abstract: International audience; We performed experiments to study the low-energy part of the E1 response (Pygmy Dipole Resonance) in $^{90,94}$Zr nuclei, by measuring the (p,p’γ) and (α,α’γ) inelastic scattering reactions at energies Ebeam,p = 80 MeV and Ebeam,α = 130 MeV respectively. The inelastically scattered particles were measured by employing the high-resolution spectrometer Grand Raiden. The gamma-rays emitted following the de-excitation of the Zr target nuclei were detected using both the clover type HPGe detectors of the CAGRA array and the large volume LaBr3:Ce scintillation detectors from the HECTOR+ array. Some preliminary results are presented here.
Published: 2017
Full Text: View/download PDF

34. Setup for the measurement of the 235U(n, f) cross section relative to n-p scattering up to 1 GeV

Author: B. Thomas, N. V. Sosnin, Annamaria Mazzone, Petar Žugec, P. Sprung, M. Bacak, V. Alcayne, Ignacio Porras, M. Krtiička, O. Aberle, A. S. Brown, M. A. Millán-Callado, G. Cortes, V. Variale, Dimitri Rochman, E. Pirovano, Arnd R. Junghans, F. Ogállar, A. Mengoni, G. Tagliente, J. Perkowski, M. Sabaté-Gilarte, J. Andrzejewski, J. Lerendegui-Marco, L. Caballero, S. Amaducci, D. Cano-Ott, P. M. Milazzo, I. Duran, A. Sekhar, M. Diakaki, R. Vlastou, E. Berthoumieux, Y. Kopatch, B. Fernández-Domíngez, E. Dupont, F. Mingrone, A. Casanovas, E. Jericha, Rugard Dressler, A. Oprea, D. Macina, Carlos Guerrero, G. Vannini, Paolo Finocchiaro, L. Cosentino, Dorothea Schumann, S. Bennett, P. Torres-Sánchez, A. Tsinganis, I. Knapova, Alexandru Negret, R. Garg, A. Stamatopoulos, M. Caamaño, S. Heinitz, F. Gunsing, M. Mastromarco, Luciano Piersanti, Nicola Colonna, P. Vaz, Massimo Barbagallo, Cristian Massimi, F. Käppeler, Vasilis Vlachoudis, Anton Wallner, Claudia Lederer-Woods, C. Petrone, P. J. Davies, Maurizio Busso, V. Furman, T. J. Wright, V. Michalopoulou, I. Ferro-Gonçalves, Z. Eleme, Deniz Kurtulgil, Ralf Nolte, Fño Calvi, Alberto Ventura, Emilio Andrea Maugeri, V-Suarez Babiano, E. Mendoza, A. Gawlik, Ariel Tarifeño-Saldivia, S. J. Lonsdale, Peter Schillebeeckx, L. A. Damone, M. Kokkoris, S. Urlass, Rene Reifarth, E. González-Romero, A. Pavlik, C. Domingo-Pardo, D. Ramos, A. Manna, P. J. Woods, N. Patronis, A. K. Saxena, Arnaud Ferrari, I. Ladarescu, J. M. Quesada, L. Tassan-Got, D. Bosnar, Sergio Cristallo, S. Valenta, Marco Calviani, A. G. Smith, M. Dietz, J. Moreno-Soto, Y. Kadi, Simone Gilardoni, U. Jiri, F. Cerutti, Javier Praena, A. Kimura, J. L. Tain, M. A. Cortés-Giraldo, A. Musumarra, T. Martinez, C. Rubbia, E. Chiaveri, P. F. Mastinu, A. Masi, Diego Vescovi, D. G. Jenkins, Q. Ducasse, Kathrin Göbel, Jan Heyse, L. Audouin, 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, Ge, Z., Shu, N., Chen, Y., Wang, W., and Zhang, H.
Subjects: Physics, High energy, Range (particle radiation), 010308 nuclear & particles physics, Scattering, Fission, QC1-999, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Detector, n_TOF, 235U, fission, neutron time of flight, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Cross section (physics), Neutron flux, 0103 physical sciences, Nuclear Physics - Experiment, Neutron, Nuclear Experiment, 010306 general physics
Abstract: The neutron induced fission of 235U is extensively used as a reference for neutron fluence measurements in various applications, ranging from the investigation of the biological effectiveness of high energy neutrons, to the measurement of high energy neutron cross sections of relevance for accelerator driven nuclear systems. Despite its widespread use, no data exist on neutron induced fission of 235U above 200 MeV. The neutron facility n_TOF offers the possibility to improve the situation. The measurement of 235U(n,f) relative to the differential n-p scattering cross-section, was carried out in September 2018 with the aim of providing accurate and precise cross section data in the energy range from 10 MeV up to 1 GeV. In such measurements, Recoil Proton Telescopes (RPTs) are used to measure the neutron flux while the fission events are detected and counted with dedicated detectors. In this paper the measurement campaign and the experimental set-up are illustrated.
Published: 2020
Full Text: View/download PDF

35. Experimental investigation of the 02+ band in Sm154 as a β-vibrational band

Author: Andrej Herzan, James Smallcombe, R.-D. Herzberg, Juha Sorri, Sami Rinta-Antila, D. G. Jenkins, Paul Greenlees, E. Parr, Janne Pakarinen, Peter M. Jones, C. J. Barton, L.-L. Andersson, Mikael Sandzelius, Paivi Nieminen, Pauli Peura, Jan Sarén, P. J. Davies, Philippos Papadakis, C. Scholey, S. Juutinen, A. Lopez-Martens, Panu Ruotsalainen, Ulrika Jakobsson, Juha Uusitalo, R. Julin, Matti Leino, K. Hauschild, Daniel Cox, P. Rahkila, T. Grahn, Steffen Ketelhut, P. A. Butler, and A. K. Mistry
Subjects: Physics, Nuclear and High Energy Physics, Silicon, 010308 nuclear & particles physics, Gamma ray, chemistry.chemical_element, Germanium, Electron, 01 natural sciences, Bohr model, symbols.namesake, Internal conversion, chemistry, 0103 physical sciences, symbols, Interacting boson model, Atomic physics, 010306 general physics, Spectroscopy
Abstract: A study of Sm 154 through γ -ray and internal conversion electron coincidence measurements was performed using the Silicon And GErmanium spectrometer (SAGE). An upper limit for the ρ 2 ( E 0 ; 2 2 + → 2 1 + ) and measurement of the ρ 2 ( E 0 ; 4 2 + → 4 1 + ) monopole transitions strengths were determined. The extracted transition strength for each is significantly lower than that predicted by either the Bohr and Mottelson β -vibration description or the interacting boson model. Hence, the long standing interpretation of these states as a collective band built on the 0 2 + state, which is conventionally assigned as a Bohr and Mottelson β vibration is questionable.
Published: 2014
Full Text: View/download PDF

36. The role of core excitations in the structure and decay of the 16(+) spin-gap isomer in Cd-96

Author: K. Moschner, H. Baba, Toshiyuki Sumikama, Y. Zhu, E. Gregor, M. Lewitowicz, Torbjörn Bäck, J. Jolie, T. Faestermann, D. G. Jenkins, Frédéric Nowacki, N. Warr, Shunji Nishimura, E. Merchan, K. Yoshinaga, Roman Gernhaeuser, H. Schaffner, A. Blazhev, N. Kurz, P. Boutachkov, F. Ameil, Hiroki Nishibata, Ayumi Yagi, I. Kojouharov, Jan Taprogge, J. Gerl, L. Maier, P. Doornenbal, Shintaro Go, D. Nishimura, H. Grawe, M. Górska, K. Steiger, H. Hotaka, T. Isobe, Ziye Xu, V. Werner, P. J. Davies, P. A. Söderström, A. Gengelbach, F. Naqvi, Hiroshi Watanabe, H. S. Jung, P. Thöle, Giuseppe Lorusso, M. Dewald, Norbert Pietralla, R. Wadsworth, 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)-Centre National de la Recherche Scientifique (CNRS), Federal Ministry of Education and Research (Germany), SCOAP, Department of Energy (US), Science and Technology Facilities Council (UK), 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), Université de Strasbourg (UNISTRA)-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 and High Energy Physics, Proton decay, Nuclear Theory, βp-decay, γ -ray spectroscopy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Shell-model, 01 natural sciences, 7. Clean energy, WKB approximation, Nuclear physics, Subatomär fysik, 0103 physical sciences, Subatomic Physics, ddc:530, Proton emission, 010306 general physics, Wave function, Nuclear Experiment, Physics, WKB, Spectrometer, Isotope, 010308 nuclear & particles physics, β-decay, Half-life, βp-decayγ-ray spectroscopy, beta p-decay, lcsh:QC1-999, β -decay, 3. Good health, gamma-ray spectroscopy, 13. Climate action, γ-ray spectroscopy, Physics::Accelerator Physics, Atomic physics, Ground state, βp -decay, lcsh:Physics, beta-decay
Abstract: P. J. Davies et al. -- 6 pags., 4 figs., 3 tabs.-- Open Access funded by Creative Commons Atribution Licence 4.0, The first evidence for β-delayed proton emission from the 16 spin gap isomer in Cd is presented. The data were obtained from the Rare Isotope Beam Factory, at the RIKEN Nishina Center, using the BigRIPS spectrometer and the EURICA decay station. βp branching ratios for the ground state and 16 isomer have been extracted along with more precise lifetimes for these states and the lifetime for the ground state decay of Cd. Large scale shell model (LSSM) calculations have been performed and WKB estimates made for ℓ=0,2,4 proton emission from three resonance-like states in Ag, that are populated by the β decay of the isomer, and the results compared to the new data. The calculations suggest that ℓ=2 proton emission from the resonance states, which reside ∼5 MeV above the proton separation energy, dominates the proton decay. The results highlight the importance of core-excited wavefunction components for the 16 state., This work was partially supported by the German BMBF grant 05P12PKFNE, the UK Science and Technology Facilities Council(STFC) grants ST/J000124/1 and ST/L005727/1, and the U.S. DOE grant DE-FG02-91ER40609.
Published: 2017
Full Text: View/download PDF

37. Spectroscopy of Kr70 and isospin symmetry in the T=1 fpg shell nuclei

Author: E. Sahin, H. Badran, Jari Partanen, Janne Pakarinen, W. Korten, D. M. Debenham, C. Scholey, Matti Leino, Joonas Konki, Panu Ruotsalainen, A.d Herzaáň, P. J. Davies, D. G. Jenkins, Rauno Julin, Philippos Papadakis, Jack Henderson, Gavin Lotay, S. Juutinen, T.a Haylett, P. Peura, Kalle Auranen, P.d Greenlees, Ulrika Jakobsson, Juha Sorri, L. Sinclair, Mikael Sandzelius, P. Joshi, M Mallaburn, H. M. David, Sanna Stolze, G. de Angelis, K.c Kaneko, R. Wadsworth, Tuomas Grahn, Juha Uusitalo, Panu Rahkila, Jan Sarén, and M. A. Bentley
Subjects: Physics, 010308 nuclear & particles physics, Shell (structure), Space (mathematics), 01 natural sciences, Symmetry (physics), Nuclear physics, medicine.anatomical_structure, Isospin, 0103 physical sciences, Isobar, medicine, Atomic physics, 010306 general physics, Spin (physics), Spectroscopy, Nucleus
Abstract: The recoil-β tagging technique has been used in conjunction with the 40 Ca(32 S ,2n) reaction at a beam energy of 88 MeV to identify transitions associated with the decay of the 2 + and, tentatively, 4 + states in the nucleus 70 Kr. These data are used, along with previously published data, to examine the triplet energy differences (TED) for the mass 70 isobars. The experimental TED values are compared with shell model calculations, performed with the JUN45 interaction in the fpg model space, that include a J = 0 isospin nonconserving (INC) interaction with an isotensor strength of 100 keV. The agreement is found to be very good up to spin 4 and supports the expectation for analog states that all three nuclei have the same oblate shape at low-spin. The A = 70 results are compared with the experimental and shell model predicted TED and mirror energy differences (MED) for the mass 66 and 74 systems. The comparisons clearly demonstrate the importance of the isotensor INC interaction in replicating the TED data in this region. Issues related to the observed MED values and their interpretation within the shell model are discussed.
Published: 2016
Full Text: View/download PDF

38. Isospin symmetry at high spin studied via nucleon knockout from isomeric states

Author: L. Scruton, S. M. Lenzi, T. W. Henry, Daniel Bazin, S. McDaniel, Alexandra Gade, D. Weisshaar, S. R. Stroberg, Scott Milne, R. Winkler, Kathrin Wimmer, A. J. Nichols, A. Lemasson, H. Iwasaki, T.R. Baugher, Alison Bruce, P. J. Davies, Edward Simpson, C. Aa. Diget, D. R. Napoli, A. Ratkiewicz, J. S. Berryman, J. A. Tostevin, M. A. Bentley, 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), and 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)
Subjects: Physics, education.field_of_study, 010308 nuclear & particles physics, Population, Nuclear Theory, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Physics and Astronomy (all), medicine.anatomical_structure, Fragmentation (mass spectrometry), Excited state, Isospin, 0103 physical sciences, medicine, Mirror nuclei, Atomic physics, 010306 general physics, education, Nucleon, Nuclear Experiment, Nucleus, Radioactive beam
Abstract: International audience; One-neutron knockout reactions have been performed on a beam of radioactive 53Co in a high-spinisomeric state. The analysis is shown to yield a highly selective population of high-spin states in an exoticnucleus with a significant cross section, and hence represents a technique that is applicable to the plannednew generation of fragmentation-based radioactive beam facilities. Additionally, the relative cross sectionsamong the excited states can be predicted to a high level of accuracy when reliable shell-model input isavailable. The work has resulted in a new level scheme, up to the 11þ band-termination state, of the protonrichnucleus 52Co (Z ¼ 27, N ¼ 25). This has in turn enabled a study of mirror energy differences inthe A ¼ 52 odd-odd mirror nuclei, interpreted in terms of isospin-nonconserving (INC) forces in nuclei.The analysis demonstrates the importance of using a full set of J-dependent INC terms to explain theexperimental observations.
Published: 2016
Full Text: View/download PDF

39. Mirrored one-nucleon knockout reactions to theTz=±32 A=53mirror nuclei

Author: Alexandra Gade, Alison Bruce, D. Weisshaar, Kathrin Wimmer, L. Scruton, T. W. Henry, S. McDaniel, A. Lemasson, S. R. Stroberg, Scott Milne, H. Iwasaki, P. J. Davies, J. S. Berryman, D. R. Napoli, Edward Simpson, C. Aa. Diget, M. A. Bentley, P. Dodsworth, A. Ratkiewicz, J. A. Tostevin, S. M. Lenzi, R. Winkler, D. Bazin, A. J. Nichols, and T.R. Baugher
Subjects: Physics, Isovector, 010308 nuclear & particles physics, Strong interaction, Charge (physics), 01 natural sciences, Excited state, 0103 physical sciences, Symmetry breaking, Mirror nuclei, Atomic physics, 010306 general physics, Nucleon, Spectroscopy
Abstract: Background: The study of excited states in mirror nuclei allows us to extract information on charge-dependent (i.e., isospin-nonconserving) interactions in nuclei. Purpose: To extend previous studies of mirror nuclei in the f7/2 region, investigating charge symmetry breaking of the strong nuclear force. Methods: γ-ray spectroscopy has been performed for the mirror (Tz= ±3/2) pair 53Ni and 53Mn, produced via mirrored one-nucleon knockout reactions. Results: Several new transitions have been identified in 53Ni from which a new level scheme has been constructed. Cross sections for knockout have been analyzed and compared with reaction model calculations where evidence is found for knockout from high-spin isomeric states. Mirror energy differences between isobaric analog states have been computed, compared to large scale shell-model calculations, and interpreted in terms of isospin-nonconserving effects. In addition, lifetimes for the long-lived J π = 5 /2 − 1 analog states in both 53Mn and 53Ni have been extracted through lineshape analysis, giving half-lives of t1/2 = 120 (14) ps and t1/2 = 198 (12) ps,respectively. Conclusions: The inclusion of a set of isovector isospin-nonconserving matrix elements to the shell-model calculations gave the best agreement with the experimental data.
Published: 2016
Full Text: View/download PDF

40. Detecting multi-hit events in a CdZnTe coplanar grid detector using pulse shape analysis: A method for improving background rejection in the COBRA experiment

Author: Pankaj S. Joshi, P. J. Davies, Martin Freer, B. R. Fulton, Daniel Muenstermann, O. Schulz, Kai Zuber, and J. McGrath
Subjects: Physics, Nuclear and High Energy Physics, Detector, Compton scattering, Cobra, Grid, Nuclear physics, Double beta decay, Pulse shape analysis, Neutrino, Instrumentation, computer, Cdznte detector, computer.programming_language
Abstract: A number of experiments are underway to search for a rare form of radioactivity, neutrinoless double beta decay, as a measurement of the half-life would enable the neutrino mass to be determined. The COBRA collaboration [1] , [2] (Zuber, 2001; Dawson, 2009) employs CdZnTe detectors in such a search. This paper describes techniques using pulse shape analysis for identifying two-centre events in a coplanar grid CdZnTe detector. This enables Compton scatter events to be identified and so suppressing the background present within the COBRA detectors.
Published: 2010
Full Text: View/download PDF

41. Triplet energy differences and the low lying structure ofGa62

Author: Edward Simpson, V. M. Bader, A. O. Macchiavelli, S. R. Stroberg, C. M. Campbell, J. S. Berryman, T. W. Henry, T.R. Baugher, R. M. Clark, D. G. Jenkins, M. A. Bentley, C. W. Beausang, A. Lemasson, H. L. Crawford, Alexandra Gade, D. Weisshaar, H. Iwasaki, C. Walz, M. Cromaz, A. Wiens, P. J. Davies, Alison Bruce, I. Y. Lee, D. R. Napoli, J. Rissanen, Stefanos Paschalis, R. Wadsworth, P. Fallon, S. M. Lenzi, Marina Petri, Jack Henderson, F. Recchia, D. Bazin, and A. J. Nichols
Subjects: Physics, Nuclear and High Energy Physics, education.field_of_study, Spins, 010308 nuclear & particles physics, Population, Structure (category theory), State (functional analysis), 01 natural sciences, Nuclear physics, Excited state, 0103 physical sciences, Isobar, Atomic physics, 010306 general physics, Spectroscopy, education
Abstract: Author(s): Henry, TW; Bentley, MA; Clark, RM; Davies, PJ; Bader, VM; Baugher, T; Bazin, D; Beausang, CW; Berryman, JS; Bruce, AM; Campbell, CM; Crawford, HL; Cromaz, M; Fallon, P; Gade, A; Henderson, J; Iwasaki, H; Jenkins, DG; Lee, IY; Lemasson, A; Lenzi, SM; Macchiavelli, AO; Napoli, DR; Nichols, AJ; Paschalis, S; Petri, M; Recchia, F; Rissanen, J; Simpson, EC; Stroberg, SR; Wadsworth, R; Weisshaar, D; Wiens, A; Walz, C | Abstract: Background: Triplet energy differences (TED) can be studied to yield information on isospin-non-conserving interactions in nuclei. Purpose: The systematic behavior of triplet energy differences (TED) of T=1, Jπ=2+ states is examined. The A=62 isobar is identified as having a TED value that deviates significantly from an otherwise very consistent trend. This deviation can be attributed to the tentative assignments of the pertinent states in Ga62 and Ge62. Methods: An in-beam γ-ray spectroscopy experiment was performed to identify excited states in Ga62 using Gamma-Ray Energy Tracking In-Beam Nuclear Array with the S800 spectrometer at NSCL using a two-nucleon knockout approach. Cross-section calculations for the knockout process and shell-model calculations have been performed to interpret the population and decay properties observed. Results: Using the systematics as a guide, a candidate for the transition from the T=1, 2+ state is identified. However, previous work has identified similar states with different Jπ assignments. Cross-section calculations indicate that the relevant T=1, 2+ state should be one of the states directly populated in this reaction. Conclusions: As spins and parities were not measurable, it is concluded that an unambiguous identification of the first T=1, 2+ state is required to reconcile our understanding of TED systematics.
Published: 2015
Full Text: View/download PDF

42. Spectroscopy and lifetime measurements inGe66,Se69, andGa65using fragmentation reactions

Author: Alexandra Gade, I. Paterson, M. Hackstein, T.R. Baugher, P. J. Davies, H. Iwasaki, A. Lemasson, K. Whitmore, D. G. Jenkins, C. Fransen, V. M. Bader, Thomas Braunroth, Jack Henderson, D. Weisshaar, A. Dewald, C. Morse, G. de Angelis, R. Wadsworth, M. A. Bentley, David Miller, J. S. Berryman, S. R. Stroberg, Kathrin Wimmer, D. Bazin, and A. J. Nichols
Subjects: Physics, Nuclear and High Energy Physics, Fragmentation (mass spectrometry), Excited state, Atomic physics, Spectroscopy
Abstract: Lifetimes of low-lying excited states have been measured in $^{66}\mathrm{Ge},^{69}\mathrm{Se}$, and $^{65}\mathrm{Ga}$ using a $\ensuremath{\gamma}$-ray lineshape method. The results confirm the previously reported ${7}_{1}^{\ensuremath{-}}$ state lifetime in $^{66}\mathrm{Ge}$. The lifetime of the yrast $5/{2}^{\ensuremath{-}}$ state in $^{65}\mathrm{Ga}$ is measured for the first time. Lifetime measurements of two excited $3/{2}^{\ensuremath{-}}$ states in $^{69}\mathrm{Se}$ are also reported. Two previously unobserved $\ensuremath{\gamma}$ rays have been identified in $^{69}\mathrm{Se}$. $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence measurements have been used to place one of these in the level scheme. $^{69}\mathrm{Se}$ excited state populations are compared to shell-model calculations using the GXPF1A interaction in the $\mathit{fp}$ model space. Theoretical spectroscopic factors to excited states in $^{69}\mathrm{Se}$ have identified three candidate levels for the origin of one of the new transitions.
Published: 2015
Full Text: View/download PDF

43. The SPEDE Spectrometer: Combined In-Beam γ-ray and Conversion Electron Spectroscopy with Radioactive Ion Beams

Author: Kimmo Ranttila, Panu Rahkila, D. G. Jenkins, Mark Huyse, Joonas Konki, Paul Greenlees, Jim Thornhill, Janne Pakarinen, Ville-Peka Saarela, Rolf-Dietmar Herzberg, David Wells, P. A. Butler, Daniel Cox, Philippos Papadakis, G. G. O'Neill, P. J. Davies, and Piet Van Duppen
Subjects: Radioactive ion beams, Physics, Large Hadron Collider, Spectrometer, ta114, Physics::Instrumentation and Detectors, Parity (physics), Coulomb excitation, Electron, Electron spectroscopy, Physics::Accelerator Physics, Silicon detector, Atomic physics, conversion electron spectrometers, Nuclear Experiment
Abstract: The SPEDE spectrometer [1] aims to combine a silicon detector, for the detection of electrons, with the MINIBALL γ-ray detection array for in-beam studies employing radioactive ion beams at the HIE-ISOLDE facility at CERN. The setup will be primarily used for octupole collectivity [2] and shape coexistence studies [3, 4] in Coulomb excitation experiments. In the shape coexistence cases the transitions between states of the same spin and parity have enhanced E0 strength [5]. Additionally the 0→0 transitions, typically present in nuclei exhibiting shape coexistence [6], can only occur via E0 transitions, i.e. via internal conversion electron emission.
Published: 2015
Full Text: View/download PDF

44. Upper limit on the two-photon emission branch for the 02+ → 01+ transition in 98Mo

Author: C. J. Lister, S. Zhu, D. G. Jenkins, M. P. Carpenter, Jack Henderson, B. P. Kay, Martín Alcorta, and P. J. Davies
Subjects: Physics, Nuclear and High Energy Physics, education.field_of_study, Branching fraction, Proton scattering, Excited state, Phase space, Population, Gammasphere, Parity (physics), Electron, Atomic physics, education
Abstract: Background: Two-photon emission, while well known in atomic physics, is a rare second-order process in nuclear physics with only three cases where a two-photon branch is measured. The limited knowledge stems from the experimental difficulty in resolving two-photon emission from dominant single-photon emission, restricting practical cases for study to ${0}^{+}\ensuremath{\rightarrow}{0}^{+}$ ($E0$) transitions, since single-photon emission is forbidden. In practical terms, this limits the range of easily accessible cases to even-even nuclei with the unusual property of a first excited state with spin/parity of 0${}^{+}$.Purpose: Two-photon branches are measured for the closed-shell nuclei, ${}^{16}\mathrm{O}$, ${}^{40}\mathrm{Ca}$, and ${}^{90}\mathrm{Zr}$. The intention of the present work was to obtain data for a case which was not a closed-shell nucleus. Of the possible nuclei relevant to such a study, ${}^{98}Mo$ was chosen as its first-excited state is 0${}^{+}$ and lies below 1 MeV, meaning that internal pair transitions are not allowed.Method: The first excited state (${J}^{\ensuremath{\pi}}={0}^{+}$) in ${}^{98}Mo$ was excited in resonant inelastic proton scattering using a 6.7-MeV proton beam. The population of the state was selected using an annular double-sided silicon strip detector (DSSD). The decay of the state by conversion electrons was observed using the same DSSD, while Gammasphere was used to detect possible two-photon events.Results: An upper limit on the two-photon branch obtained was 1 $\ifmmode\times\else\texttimes\fi{}$ 10${}^{\ensuremath{-}4}$ at the 95% confidence level (CL). Conclusions The upper limit obtained is smaller than any other previously obtained two-photon branch. Phase space considerations suggest that the actual value of the branching ratio in this case may be significantly smaller than the upper limit obtained.
Published: 2014
Full Text: View/download PDF

45. Collectivity in A∼70 nuclei studied via lifetime measurements in $^{70} $Br and $^{68,70} $Se

Author: Edward Simpson, Thomas Braunroth, Jack Henderson, T.R. Baugher, A. Dewald, K. Whitmore, M. A. Bentley, I. Paterson, A. Lemasson, P. J. Davies, V. M. Bader, Kazunari Kaneko, G. de Angelis, H. Iwasaki, D. Bazin, Alexandra Gade, A. J. Nichols, C. Fransen, D. Weisshaar, S. R. Stroberg, D. G. Jenkins, Kathrin Wimmer, M. Hackstein, R. Wadsworth, J. S. Berryman, David Miller, C. Morse, 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), and 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)
Subjects: Physics, Coupling, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Nuclear Theory, Lifetimes, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Space (mathematics), Nuclear transition probabilities, 01 natural sciences, symbols.namesake, Recoil, Isospin, 0103 physical sciences, symbols, Coulomb, Neutron, Nucleon knockout reactions, Atomic physics, Nuclear Experiment, 010306 general physics, Spin (physics), Doppler effect
Abstract: Transition strengths for decays from low-lying states in A ∼ 70 nuclei have been deduced from lifetime measurements using the recoil distance Doppler shift technique. The results confirm the collectivity previously reported for the 21+→0gs+ decay in 68 Se and reveal a relative decrease in collectivity in 70 Br. This trend is reproduced by shell model calculations using the GXPF1A interaction in an fp model space including the Coulomb, spin-orbit and isospin non-conserving interactions. The 31+→21+ decay in 70 Br is found to have a very small B(M1) value, which is consistent with the configuration of the state being dominated by the coupling of f52 protons and neutrons. The results suggest that the g92 orbit does not play an important role at low spin in these nuclei. The B(E2) values for the decays of the (T = 1) 21+ states in 70 Br and 70 Se are almost identical, suggesting there is no major shape change between the two nuclei at low spin.
Published: 2014
Full Text: View/download PDF

46. Combined in-beam gamma-ray and conversion electron spectroscopy with radioactive ion beams. Simulations of a silicon detector for the SPEDE spectrometer

Author: R. Julin, P. Rahkila, K. Ranttila, G. G. O'Neill, Marc Huyse, D. G. Jenkins, P. J. Davies, P. Van Duppen, J. Thornhill, R. D. Page, Janne Pakarinen, R.-D. Herzberg, Paul Greenlees, P. A. Butler, Joonas Konki, Philippos Papadakis, Simenel, C, Evers, M, Kibedi, T, Luong, DH, Reed, M, Srncik, M, and Wallner, A
Subjects: Physics, Ion beam, Spectrometer, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, business.industry, Gamma ray, Electron, 01 natural sciences, 7. Clean energy, Electron spectroscopy, Engineering physics, Semiconductor detector, Internal conversion, Optics, 0103 physical sciences, Physics::Accelerator Physics, Nuclear Experiment, 010306 general physics, business, Beam (structure)
Abstract: In-beam gamma-ray and electron spectroscopy have been widely used as tools to study the broad variety of phenomena in nuclear structure. The SPEDE spectrometer is a new device to be used in conjunction with the MINIBALL germanium detector array to enable the detection of internal conversion electrons in coincidence with gamma rays from de-exciting nuclei in radioactive ion beam experiments at the upcoming HIE-ISOLDE facility at CERN, Switzerland. Geant4 simulations were carried out in order to optimise the design and segmentation of the silicon detector to achieve good energy resolution and performance. ispartof: pages:1-4 ispartof: EPJ Web ofConferences vol:63 pages:1-4 ispartof: Heavy Ion Accelerator Symposium location:AUSTRALIA, Canberra date:8 Apr - 12 Apr 2013 status: published
Published: 2013

47. Spectroscopy of proton-rich66Se up toJπ=6+: Isospin-breaking effect in theA=66isobaric triplet

Author: D. G. Jenkins, Juha Sorri, R. Julin, Panu Ruotsalainen, M. Leino, R. Wadsworth, J. Pakarinen, Pauli Peura, P. J. Davies, A. J. Nichols, Kalle Auranen, C. Scholey, Ulrika Jakobsson, T. Grahn, P. Rahkila, M. A. Bentley, J. Konki, Gavin Lotay, S. Juutinen, A. Herzáň, M. Sandzelius, Jack Henderson, Sanna Stolze, Juha Uusitalo, A. Obertelli, Jukka Partanen, Pankaj S. Joshi, Jan Sarén, and Paul Greenlees
Subjects: Physics, Nuclear and High Energy Physics, Angular momentum, Proton, 010308 nuclear & particles physics, 7. Clean energy, 01 natural sciences, Excited state, Isospin, 0103 physical sciences, Coulomb, Isobaric process, Triplet state, Atomic physics, 010306 general physics, Spectroscopy
Abstract: Candidates for three excited states in the 66^Se have been identified using the recoil-{\beta} tagging method together with a veto detector for charged-particle evaporation channels. These results allow a comparison of mirror and triplet energy differences between analogue states across the A = 66 triplet as a function of angular momentum. The extracted triplet energy differences follow the negative trend observed in the f_7/2 shell. Shell-model calculations indicate a continued need for an additional isospin non-conserving interaction in addition to the Coulomb isotensor part as a function of mass.
Published: 2013
Full Text: View/download PDF

48. High-resolution spectroscopy of decay pathways in the12C(12C,γ) reaction

Author: S. Zhu, F. Haas, P. Marley, D. G. Jenkins, S. Courtin, C. J. Lister, M. Bouhelal, T. Lauritsen, T. L. Khoo, P. J. Davies, A. H. Wuosmaa, R. V. F. Janssens, D. Seweryniak, D. Lebhertz, Alexander Robinson, C. L. Jiang, David O'Donnell, J. C. Lighthall, M. P. Carpenter, and R. Wadsworth
Subjects: Nuclear reaction, Physics, Nuclear and High Energy Physics, education.field_of_study, Branching fraction, Population, Resonance, Excited state, Gammasphere, Atomic physics, Nuclear Experiment, Spectroscopy, education, Radioactive decay
Abstract: The decay branchings of a resonance in the 12C(12C,γ)24Mg reaction at Ec.m. = 8.0 MeV have been studied with high resolution using the Gammasphere array. Radiative capture residues were discriminated from scattered beam and the dominant evaporation channels using the fragment mass analyzer coupled to a multistage Parallel Grid Avalanche Counter (PGAC)/ion chamber system. The clean selection of residues has allowed the population of excited states up to 10 MeV in 24Mg to be examined in detail. Strong feeding of an excited Kπ=0− band is observed. A Jπ = 4+assignment to the resonance is strongly favored.
Published: 2011
Full Text: View/download PDF

49. Evidence for Shape Co-existence at medium spin in 76Rb

Author: Dugersuren Dashdorj, F. Johnston-Theasby, W. Reviol, B. G. Carlsson, John P. Greene, S. J. Freeman, M. P. Carpenter, Gaurab Mukherjee, D. G. Sarantites, D. G. Jenkins, P. J. Davies, F. Moore, P. E. Garrett, Hai Liang Ma, A. O. Macchiavelli, Corina Andreoiu, D. Seweryniak, Rae Austin, Andreas Görgen, J. J. Valiente-Dobón, R. Wadsworth, Pankaj S. Joshi, C. E. Svensson, and Ingemar Ragnarsson
Subjects: Physics, Nuclear reaction, Nuclear and High Energy Physics, Nuclear Theory, Spins, 010308 nuclear & particles physics, Detector, Gamma ray, FOS: Physical sciences, Parity (physics), 01 natural sciences, Charged particle, Nuclear Theory (nucl-th), 0103 physical sciences, Gammasphere, Atomic physics, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Beam energy
Abstract: Four previously known rotational bands in 76Rb have been extended to moderate spins using the Gammasphere and Microball gamma ray and charged particle detector arrays and the 40Ca(40Ca,3pn) reaction at a beam energy of 165 MeV. The properties of two of the negative-parity bands can only readily be interpreted in terms of the highly successful Cranked Nilsson-Strutinsky model calculations if they have the same configuration in terms of the number of g9/2 particles, but they result from different nuclear shapes (one near-oblate and the other near-prolate). These data appear to constitute a unique example of shape co-existing structures at medium spins., Comment: Accepted for publication in Physics Letters B
Published: 2011
Full Text: View/download PDF

50. Evidence for a spin-aligned neutron-proton paired phase from the level structure of (92)Pd

Author: Anton Khaplanov, J. Gal, Pär-Anders Söderström, B. M. Nyakó, E. Vardaci, H. Al-Azri, Pankaj S. Joshi, Tina Penick Brock, Karin Lagergren, E. Clément, P. J. Davies, Dóra Sohler, S. Bhattacharyya, Gábor Kalinka, R. Moro, Michael Taylor, F. Johnston-Theasby, Zs. Dombrádi, Roberto Liotta, K. Andgren, Torbjörn Bäck, A. Johnson, S. O. Kara, G. de Angelis, D. R. Napoli, Alejandro Algora, J. Blomqvist, A. Jungclaus, Chong Qi, A. Gadea, F. Recchia, Johan Nyberg, S. M. Lenzi, J. R. Brown, J. Timár, Bo Cederwall, G. La Rana, J. N. Scheurer, A. Di Nitto, Baharak Hadinia, J. Kownacki, S. Williams, M. Palacz, J. J. Valiente-Dobon, R. Julin, R. Wadsworth, A. Atac, Jozsef Molnar, B. S. Nara Singh, G. Sletten, F. Ghazi Moradi, M. Sandzelius, K. Juhasz, G. Jaworski, A. Dijon, A. Persson, 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), Excitations Nucléaires par Laser (ENL), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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)-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), Cederwall, B., Ghazi Moradi, F., Bäck, T., Johnson, A., Blomqvist, J., Clément, E., de France, G., Wadsworth, R., Andgren, K., Lagergren, K., Dijon, A., Jaworski, G., Liotta, R., Qi, C., Nyakó, B. M., Nyberg, J., Palacz, M., Al Azri, H., Algora, A., de Angelis, G., Ataç, A., Bhattacharyya, S., Brock, T., Brown, J. R., Davies, P., Di Nitto, A., Dombrádi, Z. s., Gadea, A., Gál, J., Hadinia, B., Johnston Theasby, F., Joshi, P., Juhász, K., Julin, R., Jungclaus, A., Kalinka, G., Kara, S. O., Khaplanov, A., Kownacki, J., LA RANA, Giovanni, Lenzi, S. M., Molnár, J., Moro, RENATA EMILIA MARIA, Napoli, D. R., Nara Singh, B. S., Persson, A., Recchia, F., Sandzelius, M., Scheurer, J. N., Sletten, G., Sohler, D., Söderström, P. A., Taylor, M. J., Timár, J., Valiente Dobón, J. J., Vardaci, Emanuele, and Williams, S.
Subjects: Nuclear Theory, Proton, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], pairing, Nuclear Theory (nucl-th), Magic number (programming), spin-alignement, Physics::Atomic and Molecular Clusters, Nuclear force, Neutron, Nuclear structure, Nuclear Experiment (nucl-ex), Spin (physics), Nuclear Experiment, Physics, Multidisciplinary, ta114, Nuclear shell model, Atomic nucleus, Física nuclear, Atomic physics
Abstract: 4 páginas, 4 figuras.-- El Pdf es la versión pre-print.-- et al., Shell structure and magic numbers in atomic nuclei were generally explained by pioneering work that introduced a strong spin–orbit interaction to the nuclear shell model potential. However, knowledge of nuclear forces and the mechanisms governing the structure of nuclei, in particular far from stability, is still incomplete. In nuclei with equal neutron and proton numbers (N = Z), enhanced correlations arise between neutrons and protons (two distinct types of fermions) that occupy orbitals with the same quantum numbers. Such correlations have been predicted to favour an unusual type of nuclear superfluidity, termed isoscalar neutron–proton pairing, in addition to normal isovector pairing. Despite many experimental efforts, these predictions have not been confirmed. Here we report the experimental observation of excited states in the N = Z = 46 nucleus 92Pd. Gamma rays emitted following the 58Ni(36Ar,2n)92Pd fusion–evaporation reaction were identified using a combination of state-of-the-art high-resolution γ-ray, charged-particle and neutron detector systems. Our results reveal evidence for a spin-aligned, isoscalar neutron–proton coupling scheme, different from the previous prediction. We suggest that this coupling scheme replaces normal superfluidity (characterized by seniority coupling) in the ground and low-lying excited states of the heaviest N = Z nuclei. Such strong, isoscalar neutron–proton correlations would have a considerable impact on the nuclear level structure and possibly influence the dynamics of rapid proton capture in stellar nucleosynthesis., This work was supported by the Swedish Research Council (contract nos 2007-4067 and 2008-5793), the Göran Gustafsson Foundation, the European Union Sixth Framework Programme ‘Integrating Infrastructure Initiative – Transnational Access’ (no. 506065; EURONS), the Hungarian Scientific Research Fund, OTKA (contract nos. K72566 and K68801), the UK Science and Technology Facilities Council (STFC), the Polish Ministry of Science and Higher Education (grant no. N N202 073935), the Spanish Ministerio de Ciencia e Innovación (contract no. FPA2007-66069), the Spanish Consolider-Ingenio 2010 Programme CPAN (CSD2007-00042), and Ankara University BIYEP project no. DPT 2005120140.
Published: 2011
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Journal

Database

Publisher

60 results on '"P. J. Davies"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources