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312 results on '"R. Menegazzo"'

251. Gamow-teller strength and particle-phonon states in149Dy from decay of its 11/2? and l/2+ 149Ho parents

Author: D. Schardt, G. Walter, R. Barden, H. Güven, J. Styczen, G. Marguier, R. Menegazzo, P. Kleinheinz, J. Blomqvist, A. Huck, and N. Roy
Subjects: Physics, Nuclear and High Energy Physics, medicine.anatomical_structure, Phonon, medicine, Particle, Nuclear fusion, Neutron, Atomic physics, Nucleus, Mass separation
Abstract: Studies of the149Ho 11/2− and 1/2+ GT-decays using on-line mass separation have established in the N=83149Dy nucleus the single neutron excitations below 1.8 MeV and members of the νf7/2×3− and νf7/2×2+ particle-phonon multiplets. Quantitative analysis of the GT-decay strength to149Dy 1qp- and 3qp-states is made in terms of the strength values measured in149Dy0 and147Tb11/2− decay.
Published: 1989
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252. Lifetime measurements and the high-spin structure of 36Cl.

Author: S Aydin, M Ionescu-Bujor, F Recchia, A Gadea, S M Lenzi, S Lunardi, C A Ur, D Bazzacco, P G Bizzeti, A M Bizzeti-Sona, M Bouhelal, G de Angelis, I Deloncle, E Farnea, A Gottardo, F Haas, T Huyuk, H Laftchiev, D Mengoni, and R Menegazzo
Published: 2015
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253. A Forma Correta de Identificar a Má Aptidão Cardiorrespiratória: Olhar Para a Direita

Author: Willian R. Menegazzo and Anderson Donelli da Silveira
Subjects: Disfunção Ventrículo Direito, Aptidão Cardiorespiratória, Infarto do Miocárdio, Reabilitação Cardíaca, Teste de Esforço/métodos, Ecocardiografia Doppler/métodos, Diseases of the circulatory (Cardiovascular) system, RC666-701
Published: 2023
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254. High resolution γ-ray spectrometry using GALILEO array

Author: D. .. Testov, J. J. Valiente-Dobon, D. .. Mengoni, F. .. Recchia, A. .. Goasduff, A. .. Boso, S. .. Lenzi, G. .. De Angelis, S. .. Bakes, C. .. Boiano, B. .. Cederwall, G. .. Colucci, M. .. Cicerchia, P. .. Colovic, F. .. Didierjean, M. .. Doncel, J. A. Duenas, F. .. Galtarossa, A. .. Gozzelino, K. .. Hadynska-Klek, R. .. Isocrate, G. .. Jaworski, P. R. John, H. .. Liu, S. .. Lunardi, R. .. Menegazzo, A. .. Mentana, V. .. Modamio, A. .. Nannini, D. R. Napoli, M. .. Palacz, G. .. Pasqualato, M. .. Rocchini, S. .. Riccetto, B. .. Saygi, E. .. Sahin, M. .. Siciliano, Yu. .. Sobolev, and S. .. Szilner
Subjects: γ-ray spectroscopy, γ-ray spectrometer, nuclear structure, nuclearstate lifetime, Physics, QC1-999
Abstract: The GALILEO γ -ray spectrometer has been constructed at the Legnaro National Laboratory of INFN (LNL-INFN). It can be coupled to advanced ancillary devices which allows nuclear structure studies employing the variety of in-beam γ -ray spectroscopy methods. Such studies beneﬁt from reactions induced by the intense stable beams delivered by the Tandem-ALPI-PIAVE accelerator complex and by the radioactive beams which will be provided by the SPES facility. In this paper we outline two experiments performed within the experimental campaign at GALILEO coupled to the EUCLIDES Si-ball and the Neutron Wall array. The ﬁrst one was aimed at spectroscopic studies in A=31 mirror nuclei and the second one at measurements of lifetimes of excited states in nuclei in the vicinity of 100 Sn.
Published: 2021
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255. Expanding benefits from cardiac resynchronization therapy to exercise‐induced left bundle branch block in advanced heart failure

Author: Fernando L. Scolari, Anderson D. Silveira, Willian R. Menegazzo, Ana Paula Chedid Mendes, Maurício Pimentel, Nadine Clausell, and Livia A. Goldraich
Subjects: Cardiac resynchronization therapy, Exercise‐induced left bundle branch block, Heart failure, Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract: Abstract Indications of cardiac resynchronization therapy (CRT) do not include exercise‐induced left bundle branch block, but functional impairment could be improved with CRT in such cases. A 57‐year‐old woman with idiopathic dilated cardiomyopathy (ejection fraction 23%) presented with New York Heart Association Class IV and recurrent hospitalizations. During heart transplant evaluation, a new onset of intermittent left bundle branch block was observed on the cardiopulmonary exercise test. CRT was implanted, and 97% resynchronization rate was achieved. In 12 month follow‐up, both clinical and prognostic exercise parameters improved. In patients with heart failure with reduced ejection fraction and no left bundle branch block at rest, exercise test can uncover electromechanical dyssynchrony that may benefit from CRT.
Published: 2020
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256. Kaon Tagging at 0° Scattering Angle for High-Resolution Decay-Pion Spectroscopy

Author: Patrick Achenbach, Joerg Reinhold, Osamu Hashimoto, Salvador Sánchez Majos, Liguang Tang, B. S. Schlimme, O. Borodina, Concettina Sfienti, V. Bozkurt, Sho Nagao, R. Böhm, T. R. Saito, Simon Širca, Alicia Sanchez Lorente, F. Schulz, Junichiro Kusaka, Naoki Arai, U. Müller, Josef Pochodzalla, Kazushige Maeda, Kyo Tsukada, Carlos Ayerbe Gayoso, L. Debenjak, Anselm Esser, Y. Fujii, Amur Margaryan, Toshiyuki Gogami, E. Kim, Mar Gómez Rodríguez, Masashi Kaneta, Damir Bosnar, C. Rappold, M. Schoth, Hiroki Kanda, Satoshi Nakamura, M. O. Distler, Michaela Thiel, Harald Merkel, S. Hirose, Ivica Friščić, and S. Lunardi, P.G. Bizzeti, Sonia Kabana, C. Bucci, M. Chiari, A. Dainese, P. Di Nezza, R. Menegazzo, A. Nannini, C. Signorini and J.J. Valiente‐Dobon
Subjects: Physics, Particle physics, Spectrometer, Scattering, QC1-999, Nuclear Theory, Bremsstrahlung, Strangeness production, Nuclear physics, Momentum, Pion, Pair production, Electron Scattering, Hypernuclei, MAMI, KAOS, Decay-Pion Spectroscopy, High Energy Physics::Experiment, Nuclear Experiment, Microtron
Abstract: At the Mainz Microtron hypernuclei can be studied by (e,e'K) reactions. By detecting the kaon which is emitted in forward direction, with the KAOS spectrometer placed at 0 scattering angle, reactions involving open strangeness production are tagged. High-resolution magnetic spectrometers are then used to coincidentally detect the mono- energetic decay-pions from mesonic two-body weak decays of light hypernuclei at rest. As a pioneering experiment has confirmed, the KAOS spectrometer is exposed to a large flux of background particles, mostly positrons from bremsstrahlung pair production. In order to increase the e ciency of kaon identification the KAOS spectrometer was modi- fied to suppress background particles at the cost of a high momentum resolution, which is less important for this experiment. This was achieved by placing up to 14 cm of lead absorbers in front of the detectors, in which positrons are blocked by forming electro- magnetic showers while the e ect on kaons is limited. An additional time-of-flight wall and a new threshold ˘ Cerenkov detector help to increase the detection e ciency of kaons.
Published: 2014

257. Transfer reactions on light exotic nuclei studied with CHIMERA detector at LNS

Author: G. Cardella, L. Acosta, F. Amorini, L. Auditore, I. Berceanu, M. Buscemi, M. B. Chatterjiee, E. DeFilippo, L. Francalanza, R. Gianì, L. Grassi, E. La Guidara, G. Lanzalone, D. Loria, T. Minniti, A. Pagano, E. V. Pagano, M. Papa, S. Pirrone, G. Politi, A. Pop, F. Porto, F. Rizzo, P. Russotto, S. Santoro, A. Trifiró, M. Trimarchi, G. Verde, LOMBARDO, IVANO, ROSATO, ELIO, VIGILANTE, MARIANO, S. Lunardi, P.G. Bizzeti, C. Bucci, M. Chiari, A. Dainese, P. Di Nezza, R. Menegazzo, A. Nannini, C. Signorini, J.J. Valiente-Dobon, G., Cardella, L., Acosta, F., Amorini, L., Auditore, I., Berceanu, M., Buscemi, M. B., Chatterjiee, E., Defilippo, L., Francalanza, R., Gianì, L., Grassi, E., La Guidara, G., Lanzalone, Lombardo, Ivano, D., Loria, T., Minniti, A., Pagano, E. V., Pagano, M., Papa, S., Pirrone, G., Politi, A., Pop, F., Porto, F., Rizzo, Rosato, Elio, P., Russotto, S., Santoro, A., Trifiró, M., Trimarchi, G., Verde, Vigilante, Mariano, Cardella, G., Acosta, L., Amorini, F., Auditore, L., Berceanu, I., Chatterjiee, M., Defilippo, E., Francalanza, L., Gianì, R., Grassi, L., La Guidara, E., Lanzalone, G., Lombardo, I., Loria, D., Minniti, T., Pagano, A., Pagano, E., Papa, M., Pirrone, S., Politi, G., Pop, A., Porto, F., Rizzo, F., Rosato, E., Russotto, P., Santoro, S., Trifirò, A., Trimarchi, M., Verde, G., and Vigilante, M.
Subjects: Physics, Elastic scattering, education.field_of_study, QC1-999, Population, Resolution (electron density), Nuclear reaction, Coincidence, Spectral line, Physics and Astronomy (all), Transfer reactions, Excited state, Center of mass, Atomic physics, education, Beam (structure)
Abstract: The kinematical coincidence method is used to extract angular distribution of elastic scattering and transfer reactions. The detected light particle energy spectra are used to extract the angular distribution with around 1° resolution in the Center of Mass (CM) system. Examples with 10Be beam are presented. In the case of proton scattering, γ-ray coincidences are used to discriminate excited levels population from elastic scattering. © Owned by the authors, published by EDP Sciences, 2014.
Published: 2014

258. ASY-EOS experiment at GSI: investigating the symmetry enenrgy at supra-satutation densities

Author: P. Russotto, M. Chartier, M. D. Cozma, E. De Filippo, A. Le Fevre, S. Gannon, A. Gašsparić, M. Kiš, S. Kupny, Y. Leifels, R. Lemmon, Q. Li, J. Lukasik, P. Marini, P. Pawlowski, S. Santoro, W. Trautmann, M. Veselsky, L. Acosta, M. Adamczyk, A. Al Ajlan, M. Al Garawi, S. Al Homaidhi, F. Amorini, L. Auditore, T. Aumann, Y. Ayyad, V. Baran, Z. Basrak, R. Bassini, J. Benlliure, C. Boiano, C. Boisjoli, K. Boretzky, J. Brzychczyk, A. Budzanowski, G. Cardella, P. Cammarata, Z. Chajecki, A. Chbihi, M. Colonna, B. Czech, M. Di Toro, M. Famiano, V. Greco, L. Grassi, C. Guazzoni, P. Guazzoni, M. Heil, L. Heilborn, R. Introzzi, T. Isobe, K. Kezzar, A. Krasznahorskay, N. Kurz, E. La Guidara, G. Lanzalone, P. Lasko, W. G. Lynch, Z. Matthews, L. May, T. Minniti, M. Mostazo, A. Pagano, M. Papa, S. Pirrone, R. Pleskac, G. Politi, F. Porto, R. Reifarth, W. Reisdorf, F. Riccio, F. Rizzo, D. Rossi, H. Simon, I. Skwirczynska, Z. Sosin, L. Stuhl, A. Trifirò, M. Trimarchi, M. B. Tsang, G. Verde, A. Wieloch, P. Wigg, H. H. Wolter, P. Wu, S. Yennello, P. Zambon, L. Zetta, M. Zoric, LOMBARDO, IVANO, ROSATO, ELIO, VIGILANTE, MARIANO, S. Lunardi, P.G. Bizzeti, C. Bucci, M. Chiari, A. Dainese, P. Di Nezza, R. Menegazzo, A. Nannini, C. Signorini, J.J. Valiente-Dobon, P., Russotto, M., Chartier, M. D., Cozma, E., De Filippo, A., Le Fevre, S., Gannon, A., Gašsparić, M., Kiš, S., Kupny, Y., Leifel, R., Lemmon, Q., Li, J., Lukasik, P., Marini, P., Pawlowski, S., Santoro, W., Trautmann, M., Veselsky, L., Acosta, M., Adamczyk, A., Al Ajlan, M., Al Garawi, S., Al Homaidhi, F., Amorini, L., Auditore, T., Aumann, Y., Ayyad, V., Baran, Z., Basrak, R., Bassini, J., Benlliure, C., Boiano, C., Boisjoli, K., Boretzky, J., Brzychczyk, A., Budzanowski, G., Cardella, P., Cammarata, Z., Chajecki, A., Chbihi, M., Colonna, B., Czech, M., Di Toro, M., Famiano, V., Greco, L., Grassi, C., Guazzoni, P., Guazzoni, M., Heil, L., Heilborn, R., Introzzi, T., Isobe, K., Kezzar, A., Krasznahorskay, N., Kurz, E., La Guidara, G., Lanzalone, P., Lasko, Lombardo, Ivano, W. G., Lynch, Z., Matthew, L., May, T., Minniti, M., Mostazo, A., Pagano, M., Papa, S., Pirrone, R., Pleskac, G., Politi, F., Porto, R., Reifarth, W., Reisdorf, F., Riccio, F., Rizzo, Rosato, Elio, D., Rossi, H., Simon, I., Skwirczynska, Z., Sosin, L., Stuhl, A., Trifirò, M., Trimarchi, M. B., Tsang, G., Verde, Vigilante, Mariano, A., Wieloch, P., Wigg, H. H., Wolter, P., Wu, S., Yennello, P., Zambon, L., Zetta, and M., Zoric
Subjects: flow, NUCLEAR COLLISIONS
Abstract: The elliptic-flow ratio of neutrons with respect to protons or light complex particles in reactions of heavy-ions at pre-relativistic energies has been proposed as an observable sensitive to the strength of the symmetry term of the nuclear equation of state at supra-saturation densities. The results obtained from the existing FOPI/LAND data for 197Au+197Au collisions at 400 MeV/nucleon in comparison with the UrQMD model simulations favoured a moderately soft symmetry term, but suffer from a considerable statistical uncertainty. These results have been confirmed by an independent analysis based on the Tübingen QMD simulations. In order to obtain an improved data set for Au+Au collisions and to extend the study to other systems, a new experiment was carried out at the GSI laboratory by the ASY-EOS collaboration. The present status of the data analysis is reported
Published: 2014

259. Probing the symmetry energy at low density using observables from neck fragmentation

Author: G. Cardella, Lucrezia Auditore, M. Trimarchi, Michele Papa, R. Planeta, A. Trifirò, A. Grzeszczuk, L. Zetta, Maria Colonna, E. La Guidara, Mariano Vigilante, G. Politi, F. Porto, Giuseppe Verde, F. Rizzo, L. Acosta, S. Pirrone, C. Maiolino, K. Siwek-Wilczyńska, E. V. Pagano, I. Skwira-Chalot, F. Amorini, Ji-Youn Han, C. Agodi, J. Wilczyński, E. Piasecki, Triestino Minniti, G. Lanzalone, A. Pagano, P. Guazzoni, R. Gianì, I. Berceanu, E. Geraci, Ivano Lombardo, Amalia Pop, V. Baran, T. Cap, L. Quattrocchi, L. Grassi, P. Russotto, Elio Rosato, E. De Filippo, L. Francalanza, S. Lunardi, P.G. Bizzeti, C. Bucci, M. Chiari, A. Dainese, P. Di Nezza, R. Menegazzo, A. Nannini, C. Signorini, J.J. Valiente-Dobon, E., Defilippo, L., Acosta, C., Agodi, F., Amorini, A., Anzalone, L., Auditore, V. Baran I., Berceanu, T., Cap, G., Cardella, M., Colonna, L., Francalanza, E., Geraci, R., Gianì, L., Grassi, A., Grzeszcuk, P., Guazzoni, J., Han, E., La Guidara, G., Lanzalone, Lombardo, Ivano, C., Maiolino, T., Minniti, A., Pagano, E. V., Pagano, M., Papa, E., Piasecki, R., Planeta, S., Pirrone, G., Politi, A., Pop, F., Porto, L., Quattrocchi, F., Rizzo, Rosato, Elio, P., Russotto, K., Siwek Wilczynska, I., Skwira Chalot, A., Trifiró, M., Trimarchi, G., Verde, Vigilante, Mariano, J., Wilczynski, and L., Zetta
Subjects: Physics, Projectile, QC1-999, Observable, ionic collisions, isospin-dependent quantum, Fragmentation (mass spectrometry), fragmentation, fragments, Low density, Incident energy, NUCLEAR COLLISIONS, Atomic physics, Nuclear Experiment
Abstract: Semi-peripheral collisions of ^{64}Ni + ^{124}Sn in direct and inverse kinematics, at 35 A MeV incident energy, are studied to characterize the dynamical origin and align-ments properties of fragments emission at midrapidity. This emission is partly due to the fragmentation of a transient neck joining the projectile and target in the early stages of the reaction. Recently we exploited observable from neck fragmentation to constraint the density dependence of the symmetry energy. In this contribution we focus on the density evolution of the mid-rapidity source. An experimental survey is suggested to check if data are consistent with the formation of neck fragments in a dilute density region in contact with the projectile-like and target-like spectators at normal saturation density.
Published: 2014

260. The european FAZIA initiative: a high-performance digital telescope array for heavy-ion studies

Author: Giovanni Casini, N. Le Neindre, Paola Marini, Gabriele Pasquali, G. Pastore, A. Ordine, D. Gruyer, J.D. Frankland, B. Borderie, E. Bonnet, Maurizio Bini, Silvia Piantelli, E. Vient, R. Bougault, F. Salomon, S. Carboni, M. F. Rivet, M. Guerzoni, Tommaso Marchi, Elio Rosato, Sandro Barlini, Luca Morelli, Mariano Vigilante, Giacomo Poggi, A. Chbihi, M. Bruno, A. Kordjasz, Andrea Stefanini, O. Lopez, Alessandro Olmi, M. Pârlog, M. Degerlier, T. Twaróg, M. Cinausero, G. Spadaccini, Simone Valdré, T. Kozik, P. Edelbruck, F. Gramegna, Istituto Nazionale di Fisica Nucleare, Sezione di Firenze (INFN, Sezione di Firenze), Istituto Nazionale di Fisica Nucleare (INFN), 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), 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), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Istituto Nazionale di Fisica Nucleare, Sezione di Napoli (INFN, Sezione di Napoli), FAZIA, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), S. Lunardi, P.G. Bizzeti, C. Bucci, M. Chiari, A. Dainese, P. Di Nezza, R. Menegazzo, A. Nannini, C. Signorini, J.J. Valiente-Dobon, G., Casini, S., Barlini, G., Pasquali, G., Pastore, M., Bini, S., Carboni, A., Olmi, S., Piantelli, G., Poggi, A. A., Stefanini, S., Valdré, E., Bonnet, B., Borderie, R., Bougault, M., Bruno, A., Chbihi, M., Cinausero, M., Degerlier, P., Edelbruck, J. D., Frankland, F., Gramegna, D., Gruyer, M., Guerzoni, A., Kordyasz, T., Kozik, N., Le Neindre, O., Lopez, T., Marchi, P., Marini, L., Morelli, Ordine, Antonio, M., Parlog, M. F., Rivet, Rosato, Elio, F., Salomon, Spadaccini, Giulio, T., Twarog, E., Vient, and Vigilante, Mariano
Subjects: Charged Particle Detector, Physics - Instrumentation and Detectors, Preamplifier, Computer science, QC1-999, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, law.invention, Telescope, pulse shape discrimination, law, 0103 physical sciences, Electronics, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Aerospace engineering, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, 010308 nuclear & particles physics, business.industry, Physics, Instrumentation and Detectors (physics.ins-det), Modular design, Identification (information), isotopic identification, Pulse shape analysis, Heavy ion, business, New Facilities and Instrumentation, Product identification
Abstract: The european Fazia collaboration aims at building a new modular array for charged product identification to be employed for heavy-ion studies. The elementary module of the array is a Silicon-Silicon-CsI telescope, optimized for ion identification also via pulse shape analysis. The achievement of top performances imposes specific electronics which has been developed by FAZIA and features high quality charge and current preamplifiers, coupled to fully digital front-end. During the initial R&D phase, original and novel solutions have been tested in prototypes, obtaining unprecedented ion identification capabilities. FAZIA is now constructing a demonstrator array consisting of about two hundreds telescopes arranged in a compact and transportable configuration. In this contribution, we mainly summarize some aspects studied by FAZIA to improve the ion identification. Then we will briefly discuss the FAZIA program centered on experiments to be done with the demonstrator. First results on the isospin dynamics obtained with a reduced set-up demonstrate well the performance of the telescope and represent a good starting point towards future investigations with both stable and exotic beams., 8 pages, 2 figures, Contribution to conference proceedings of the 25th International Nuclear Physics Conference (INPC 2013) Journal-ref: 25th International Nuclear Physics Conference (INPC 2013), Firenze : Italy (2013)
Published: 2013
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261. Isospin transport in 84Kr+112,124Sn reactions at Fermi energies

Author: M. Cinausero, M.F. Rivet, N. Le Neindre, R. Bougault, T. Marchi, R. Alba, Sandro Barlini, Gabriele Pasquali, T. Twaróg, D. Gruyer, G. Spadaccini, O. Lopez, Elio Rosato, B. Borderie, Giovanni Casini, E. Bonnet, J.D. Frankland, Tomasz Kozik, Maurizio Bini, Silvia Piantelli, Alessandro Olmi, Luca Morelli, M. Parlog, A. Chbihi, Giacomo Poggi, E. Vient, C. Maiolino, Andrea Stefanini, F. Gramegna, M. Bruno, S. Carboni, P. R. Maurenzig, M. Degerlier, Mariano Vigilante, Domenico Santonocito, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), 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), FAZIA, Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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), S. Lunardi, P.G. Bizzeti, C. Bucci, M. Chiari, A. Dainese, P. Di Nezza, R. Menegazzo, A. Nannini, C. Signorini, J.J. Valiente-Dobon, S., Piantelli, G., Casini, A., Olmi, S., Barlini, M., Bini, S., Carboni, P. R., Maurenzig, G., Pasquali, G., Poggi, A. A., Stefanini, R., Bougault, N., Le Neindre, O., Lopez, M., Pârlog, E., Vient, E., Bonnet, A., Chbihi, J. D., Frankland, D., Gruyer, Rosato, Elio, Spadaccini, Giulio, Vigilante, Mariano, B., Borderie, M. F., Rivet, M., Bruno, L., Morelli, M., Cinausero, M., Degerlier, F., Gramegna, T., Marchi, R., Alba, C., Maiolino, D. Santonocito T., Kozik, and T., Twaróg
Subjects: Nuclear reaction, Physics, Density gradient, QC1-999, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nuclear reaction, Ion, isotopic identification, Diffusion process, Isospin, Nuclear reactions, Nuclear Experiment (nucl-ex), Atomic physics, Nuclear Experiment, Transport phenomena, Beam (structure), Nuclear Physics, Fermi Gamma-ray Space Telescope
Abstract: Isospin transport phenomena in dissipative heavy ion collisions have been investigated at Fermi energies with a beam of 84Kr at 35AMeV. A comparison of the /Z of light and medium products forward-emitted in the centre of mass frame when the beam impinges on a n-poor 112Sn and a n-rich 124Sn targets is presented. Data were collected by means of a three-layer telescope with very good performances in terms of mass identification (full isotopic resolution up to Z about 20 for ions punching through the first detector layer) built by the FAZIA Collaboration and located just beyond the grazing angle for both reactions. The /Z of the decay products emitted when the n-rich target is used is always higher than that associated to the n-poor one. Since the detector was able to measure only fragments coming from the QuasiProjectile decay and/or neck emission, the observed behaviour can be ascribed to the isospin diffusion, driven by the isospin gradient between QuasiProjectile and QuasiTarget. Moreover, for light fragments the /Z as a function of the lab velocity of the fragment increases when we move from the QuasiProjectile velocity to the centre of mass (neck zone). This effect can be interpreted as an evidence of isospin drift driven by the density gradient between the QuasiProjectile zone (at normal density) and the more diluted neck zone., Comment: 4 pages, 3 figures, Contribution to conference proceedings of the 25th International Nuclear Physics Conference (INPC 2013) Journal-ref: 25th International Nuclear Physics Conference (INPC 2013), Firenze : Italy (2013)
Published: 2013
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262. Decay competition for IMF produced in the collisions 78Kr+40Ca and 86Kr+48Ca at 10 A*MeV

Author: G. Cardella, Maria Colonna, D. Loria, Giuseppe Verde, S. Pirrone, F. Porto, M. La Commara, W. U. Schroeder, G. Ademard, Jan Toke, Elio Rosato, E. Geraci, J.P. Wieleczko, E. La Guidara, I. Berceanu, C. Beck, G. Spadaccini, E. De Filippo, E. Henry, F. Amorini, Eric Bonnet, A. Chbihi, Michele Papa, A. Pagano, Mariano Vigilante, M.F. Rivet, M. Quinlann, Antonio Trifiro, G. Lanzalone, Ivano Lombardo, P. Lautesse, M. Trimarchi, K. Mazurek, N. Le Neindre, Lucrezia Auditore, J.D. Frankland, D. Lebhertz, G. Politi, P. Russotto, F. Rizzo, E. Piasecki, B. Borderie, 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), 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 Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), S. Lunardi, P.G. Bizzeti, C. Bucci, M. Chiari, A. Dainese, P. Di Nezza, R. Menegazzo, A. Nannini, C. Signorini, J.J. Valiente-Dobon, LA COMMARA, Marco, S., Pirrone, G., Politi, J. P., Wieleczko, G., Ademard, E., De Filippo, Vigilante, Mariano, F., Amorini, L., Auditore, C., Beck, I., Berceanu, E., Bonnet, B., Borderie, G., Cardella, A., Chbihi, M., Colonna, J. D., Frankland, E., Geraci, E., Henry, E., La Guidara, G., Lanzalone, P., Lautesse, D., Lebhertz, N., Le Neindre, Lombardo, Ivano, D., Loria, K., Mazurek, A., Pagano, M., Papa, E., Piasecki, F., Porto, M., Quinlann, F., Rizzo, Rosato, Elio, P., Russotto, W. U., Schroeder, Spadaccini, Giulio, A., Trifirò, J., Tõke, M., Trimarchi, G., Verde, and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear reaction, Physics, Fusion, 010308 nuclear & particles physics, QC1-999, compound nucleu, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, Excited state, Isospin, 0103 physical sciences, fragments, Nuclear reactions, Atomic physics, 010306 general physics
Abstract: Expérience GANIL; International audience; Decay modes of excited compound systems 118Ba and 134Ba, produced respectively in the 78Kr+40Ca and 86Kr+48Ca collisions at 10 A*MeV, are investigated. In particular, the competition between the various disintegration path of medium mass compound nuclei, formed by fusion processes, the production of the so referred Intermediate Mass Fragments (IMF), and the isospin dependence of the decay process are studied. Data were taken at the INFN-Laboratori Nazionali del Sud (LNS) by using the CHIMERA array. Data analysis is in progress; a first indication on the average-energy angular distributions suggests pre-equilibrium effects affecting the data and the presence of isotopical effects.
Published: 2013
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263. Impact of a revised $^{25}$Mg(p,$\gamma$)$^{26}$Al reaction rate on the operation of the Mg-Al cycle

Author: Daniel Bemmerer, H. P. Trautvetter, Michele Marta, Gianluca Imbriani, Carlo Broggini, A. Lemut, Luciano Piersanti, H. Costantini, Oscar Straniero, Filippo Terrasi, Vincenzo Roca, Gyuri Gyürky, Frank Strieder, Paolo Prati, C. Mazzocchi, A. Guglielmetti, B. Limata, C. Gustavino, M. Junker, A. Formicola, Roberto Menegazzo, G. Gervino, C. Rolfs, C. Rossi Alvarez, Sergio Cristallo, Antonio Caciolli, E. Somorjai, Z. Elekes, P. Corvisiero, Zsolt Fülöp, A. DiLeva, O., Straniero, Imbriani, Gianluca, F., Strieder, D., Bemmerer, C., Broggini, A., Caciolli, P., Corvisiero, H., Costantini, S., Cristallo, DI LEVA, Antonino, A., Formicola, Z., Eleke, Fülöp, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gyürky, G. y., M., Junker, A., Lemut, B., Limata, M., Marta, C., Mazzocchi, R., Menegazzo, L., Piersanti, P., Prati, Roca, Vincenzo, C., Rolf, C., Rossi Alvarez, E., Somorjai, F., Terrasi, and H. P., Trautvetter
Subjects: Nuclear reaction, Proton, globular clusters: general, nuclear reactions, nucleosynthesis, abundances, stars: AGB and post-AGB, stars: WolfRayet, Astronomy and Astrophysics, Space and Planetary Science, astrofisica nucleare, Astrophysics, Evoluzione stellare, Chemical kinetics, Reaction rate, Nucleosynthesis, Nuclear astrophysics, Asymptotic giant branch, Nuclear Experiment, Physics, abundances, Presolar grains, Nuclear reactions, nucleosynthesis, abundances — Stars: AGB and post-AGB — Stars: Wolf-Rayet — globular clusters: general, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: Proton captures on Mg isotopes play an important role in the Mg-Al cycle active in stellar H-burning regions. In particular, low-energy nuclear resonances in the $^{25}$Mg(p,$\gamma$)$^{26}$Al reaction affect the production of radioactive $^{26}$Al$^{gs}$ as well as the resulting Mg/Al abundance ratio. Reliable estimations of these quantities require precise measurements of the strengths of low-energy resonances. Based on a new experimental study performed at LUNA, we provide revised rates of the $^{25}$Mg(p,$\gamma$)$^{26}$Al$^{gs}$ and the $^{25}$Mg(p,$\gamma$)$^{26}$Al$^{m}$ reactions with corresponding uncertainties. In the temperature range 50 to 150 MK, the new recommended rate of the $^{26}$Al$^{m}$ production is up to 5 times higher than previously assumed. In addition, at T$=100$ MK, the revised total reaction rate is a factor of 2 higher. Note that this is the range of temperature at which the Mg-Al cycle operates in an H-burning zone. The effects of this revision are discussed. Due to the significantly larger $^{25}$Mg(p,$\gamma$)$^{26}$Al$^{m}$ rate, the estimated production of $^{26}$Al$^{gs}$ in H-burning regions is less efficient than previously obtained. As a result, the new rates should imply a smaller contribution from Wolf-Rayet stars to the galactic $^{26}$Al budget. Similarly, we show that the AGB extra-mixing scenario does not appear able to explain the most extreme values of $^{26}$Al/$^{27}$Al, i.e. $>10^{-2}$, found in some O-rich presolar grains. Finally, the substantial increase of the total reaction rate makes the hypothesis of a self-pollution by massive AGBs a more robust explanation for the Mg-Al anticorrelation observed in Globular-Cluster stars.
Published: 2012

264. The25Mg(p, Î³)26Al reaction at low astrophysical energies

Author: A. Best, M. Junker, Antonio Caciolli, E. Somorjai, C. Rolfs, A. Lemut, Z. Elekes, P. Corvisiero, C. Gustavino, Oscar Straniero, Frank Strieder, Gianluca Imbriani, Michele Marta, Filippo Terrasi, A. Formicola, C. Rossi Alvarez, Daniel Bemmerer, H. P. Trautvetter, Vincenzo Roca, A. DiLeva, Paolo Prati, Zsolt Fülöp, B. Limata, Roberto Menegazzo, Gyuri Gyürky, G. Gervino, A. Guglielmetti, H. Costantini, Carlo Broggini, C. Mazzocchi, F., Strieder, Limata, BENEDICTA NORMANNA, A., Formicola, Imbriani, Gianluca, M., Junker, D., Bemmerer, Best, Andrea, C., Broggini, A., Caciolli, P., Corvisiero, H., Costantini, DI LEVA, Antonino, Z., Eleke, Fülöp, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gyürky, G. y., A., Lemut, M., Marta, C., Mazzocchi, R., Menegazzo, P., Prati, Roca, Vincenzo, C., Rolf, C., Rossi Alvarez, E., Somorjai, O., Straniero, F., Terrasi, and H. P., Trautvetter
Subjects: Physics, Nuclear and High Energy Physics, Nuclear astrophysic, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Resolution (electron density), Resonance, Mg-Al cycle, Nuclear astrophysics, Proton-capture reaction, Reaction rate, Resonance strength, Crystal, Nuclear physics, Underground laboratory, High Energy Physics::Experiment, Atomic physics, Hpge detector, Nuclear Experiment
Abstract: In the present work we report on a new measurement of resonance strengths in the reaction 25Mg(p,gamma)26Al at E_cm= 92 and 189 keV. This study was performed at the LUNA facility in the Gran Sasso underground laboratory using a 4pi BGO summing crystal. For the first time the 92 keV resonance was directly observed and a resonance strength omega-gamma=(2.9+/-0.6)x10E-10 eV was determined. Additionally, the gamma-ray branchings and strength of the 189 keV resonance were studied with a high resolution HPGe detector yielding an omega-gamma value in agreement with the BGO measurement, but 20% larger compared to previous works.
Published: 2012

265. An actively vetoed Clover γ-detector for nuclear astrophysicsat LUNA

Author: Luna, Collaboration, Szucs, T., Bemmerer, D., Broggini, C., Caciolli, A., Confortola, F., Corvisiero, P., Elekes, Z., Formicola, A., Fulop, Zs, Gervino, G., Guglielmetti, A., Gustavino, C., Gyurky, Gy, Imbriani, G., Junker, M., Lemut, A., Marta, M., Mazzocchi, C., Menegazzo, R., Prati, P., Roca, V., Rolfs, C., Rossi Alvarez, C., Somorjai, E., Oscar Straniero, Strieder, F., Terrasi, F., Trautvetter, H. P., T., Szuc, D., Bemmerer, C., Broggini, A., Caciolli, F., Confortola, P., Corvisiero, Z., Eleke, A., Formicola, F¨ul¨op, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gy¨urky, G. y., Imbriani, Gianluca, M., Junker, A., Lemut, M., Marta, C., Mazzocchi, R., Menegazzo, P., Prati, Roca, Vincenzo, C., Rolf, C., Rossi Alvarez, E., Somorjai, O., Straniero, F., Strieder, F., Terrasi, and H. P., Trautvetter
Subjects: Physics, Nuclear and High Energy Physics, Clover type HP Germaniun detector, Physics::Instrumentation and Detectors, Detector, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Underground Laboratories, Semiconductor detector, Nuclear physics, Nuclear astrophysics, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment, Nuclear Astrophysic
Abstract: An escape-suppressed, composite high-purity germanium detector of the Clover type has been installed at the Laboratory for Underground Nuclear Astrophysics (LUNA) facility, deep underground in the Gran Sasso Laboratory, Italy. The laboratory gamma-ray background of the Clover detector has been studied underground at LUNA and, for comparison, also in an overground laboratory. Spectra have been recorded both for the single segments and for the virtual detector formed by online addition of all four segments. The effect of the escape-suppression shield has been studied as well. Despite their generally higher intrinsic background, escape-suppressed detectors are found to be well suited for underground nuclear astrophysics studies. As an example for the advantage of using a composite detector deep underground, the weak ground state branching of the Ep = 223 keV resonance in the 24Mg(p,gamma)25Al reaction is determined with improved precision., 8 pages, 6 figures, 3 tables; as accepted by Eur. Phys. J. A
Published: 2010

266. Direct measurement of the 15N(p,gamma)16O total cross section at novae energies

Author: C. Rossi Alvarez, Z. Elekes, Roberto Menegazzo, Daniel Bemmerer, G. Gervino, Carlo Broggini, Vincenzo Roca, A. Formicola, Paolo Prati, P. Corvisiero, Zs. Fülöp, Antonio Caciolli, C. Gustavino, M. Junker, E. Somorjai, Oscar Straniero, R. Bonetti, H. Costantini, F. Confortola, A. Guglielmetti, C. Rolfs, Gy. Gyürky, M. Marta, B. Limata, D., Bemmerer, A., Caciolli, R., Bonetti, C., Broggini, F., Confortola, P., Corvisiero, H., Costantini, Z., Eleke, A., Formicola, Zs F¨, Ul¨op, G., Gervino, A., Guglielmetti, C., Gustavino, Gy, Gy¨urky, M., Junker, Limata, BENEDICTA NORMANNA, M., Marta, R., Menegazzo, P., Prati, Roca, Vincenzo, C., Rolf, C., Rossi Alvarez, E., Somorjai, and O., Straniero
Subjects: Nuclear and High Energy Physics, CNO cycle, Hydrogen, chemistry.chemical_element, FOS: Physical sciences, Nova burning, CNO cycle, Bismuth germanate, chemistry.chemical_compound, Cross section (physics), Nuclear Experiment (nucl-ex), Nuclear Experiment, Solar and Stellar Astrophysics (astro-ph.SR), Physics, gas target, novae astrophysics, Nova (laser), Nitrogen, Isotopic composition, LUNA, Astrophysics - Solar and Stellar Astrophysics, chemistry, nuclear astrophisic, Nuclear astrophysics, BGO detector, Center of mass, Atomic physics
Abstract: The 15N(p,gamma)16O reaction controls the passage of nucleosynthetic material from the first to the second carbon-nitrogen-oxygen (CNO) cycle. A direct measurement of the total 15N(p,gamma)16O cross section at energies corresponding to hydrogen burning in novae is presented here. Data have been taken at 90-230 keV center-of-mass energy using a windowless gas target filled with nitrogen of natural isotopic composition and a bismuth germanate summing detector. The cross section is found to be a factor two lower than previously believed., Comment: LUNA collaboration; accepted by J. Phys. G
Published: 2009
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267. Measurement of 25Mg(p,γ)26Al resonance strengths via gamma spectrometry

Author: Formicola, A., Best, A., Imbriani, G., Junker, M., Bemmerer, D., Bonetti, R., Broggini, C., Caciolli, A., Confortola, F., Corvisiero, P., Costantini, H., Elekes, Z., Fülöp, Z., Gervino, G., Guglielmetti, A., Gyürky, G., Gustavino, C., Lemut, A., Limata, B., Marta, M., Mazzocchi, C., Menegazzo, R., Prati, P., Roca, V., Rolfs, C., Rossi Alvarez, C., Somorjai, E., Straniero, O., Strieder, F., Terrasi, F., Trautvetter, H. P., A., Formicola, A., Best, G., Imbriani, M., Junker, D., Bemmerer, R., Bonetti, C., Broggini, A., Caciolli, F., Confortola, P., Corvisiero, H., Costantini, Z., Eleke, Fulop, Z. S., G., Gervino, A., Guglielmetti, G., Gyurky, C., Gustavino, A., Lemut, B., Limata, M., Marta, C., Mazzocchi, R., Menegazzo, P., Prati, V., Roca, C., Rolf, C., ROSSI ALVAREZ, E., Somorjai, O., Straniero, F., Strieder, Terrasi, Filippo, and H. P., Trautvetter
Subjects: LUNA, Experiment, Nuclear Astrophysics, Resonance strengths
Abstract: The COMPTEL instrument performed the first mapping of the 1.809 MeV photons in the Galaxy, triggering considerable interest in determing the sources of interstellar 26Al. The predicted 26Al is too low compared to the observation, for a better understanding more accurate rates for the 25Mg(p,gamma)26Al reaction are required. The 25Mg(p,gamma)26Al reaction has been investigated at the resonances at Er= 745; 418; 374; 304 keV at Ruhr-Universität Bochum using a Tandem accelerator and a 4pi NaI detector. In addition the resonance at Er = 189 keV has been measured deep underground laboratory at Laboratori Nazionali del Gran Sasso, exploiting the strong suppression of cosmic background. This low resonance has been studied with the 400 kV LUNA accelerator and a HPGe detector. The preliminary results of the resonance strengths will be reported.
Published: 2008

268. Search for tensor couplings in the weak interaction: a study of the $^{6}$He beta-decay in a Paul trap

Author: Méry, A., Ban, G., Blieck, J., Durand, D., Duval, F., Fléchard, X., Herbane, M., Labalme, M., Lemière, Y., Liénard, E., Mauger, F., Naviliat-Cuncic, O., Rodriguez, D., Thomas, J.C., Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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), G. Cuttone, A. Gadea, M. Lattuada, S. Lunardi, R. Menegazzo, D. Pierroutsakou, C. Signorini, F. Soramel, L. Tecchio, A. Vitturi, Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Guesnon, Sandrine
Subjects: [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Published: 2006

269. Shape coexistence in neutron-deficient Krypton isotopes studied by low-energy Coulomb excitation of radioactive ion beams

Author: Görgen, A., Clément, E., Korten, W., Bouchez, E., Chatillon, A., Hürstel, A., Le Coz, Y., Theisen, Ch., Wilson, J.N., Andreoiu, C., Becker, F., Butler, P., Casandjian, J.M., Catford, W.N., Czosnyka, T., de France, G., Gerl, J., Herzberg, R.-D., Iwanicki, J., Jenkins, D.G., Jones, G.D., Napiorkowski, P.J., Sletten, G., Timis, C., Zielinska, M., Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Helmholtz zentrum für Schwerionenforschung GmbH (GSI), European Organization for Nuclear Research (CERN), 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), G. Cuttone, A. Gadea, M. Lattuada, S. Lunardi, R. Menegazzo, D. Pierroutsakou, C. Signorini, F. Soramel, L. Tecchio, A. Vitturi, Lion, Michel, 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: [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Published: 2006

270. Experimental observation of $^{7}$H

Author: Caamano, M., Cortina-Gil, D., Mittig, W., Savajols, H., Caballero, L., Chartier, M., Demonchy, C.E., Fernandez, B., Gillibert, A., Gomez Hornillos, B., Jurado, B., Kiselev, O., Lemmon, R., Obertelli, A., Rejmund, F., Rejmund, M., Roussel-Chomaz, P., Wolski, R., 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), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), G. Cuttone, A. Gadea, M. Lattuada, S. Lunardi, R. Menegazzo, D. Pierroutsakou, C. Signorini, F. Soramel, L. Tecchio, A. Vitturi, 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 Lion, Michel
Subjects: [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2006

271. Radioactive beams at GANIL: present and future

Author: Lewitowicz, M., Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), G. Cuttone, A. Gadea, M. Lattuada, S. Lunardi, R. Menegazzo, D. Pierroutsakou, C. Signorini, F. Soramel, L. Tecchio, A. Vitturi, and Lion, Michel
Subjects: [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Published: 2006

272. Low energy measurement of the 14N(p,γ)15O total cross section at the LUNA underground facility

Author: Bemmerer, D., Confortola, F., Lemut, A., Bonetti, R., Broggini, C., Corvisiero, P., Costantini, H., Cruz, J., Formicola, A., Fülöp, Z. s., Gervino, Gianpiero, Guglielmetti, A., Gustavino, C., Gyürky, G. y., Imbriani, G., Jesus, A., Junker, M., Limata, B., Menegazzo, R., Prati, P, Roca, V., Rolfs, C., Rogalla, D., Romano, M., Rossi Alvarez, C., Schümann, F., Somorjai, E., Straniero, O., Strieder, F., Terrasi, F., Trautvetter, H. P., D., Bemmerer, F., Confortola, A., Lemut, R., Bonetti, C., Broggini, P., Corvisiero, H., Costantini, J., Cruz, A., Formicola, Fülöp, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gyürky, G. y., Imbriani, Gianluca, A., Jesu, M., Junker, B., Limata, R., Menegazzo, P., Prati, Roca, Vincenzo, C., Rolf, D., Rogalla, Romano, Mario, C., Rossi Alvarez, F., Schümann, E., Somorjai, O., Straniero, F., Strieder, F., Terrasi, and H. P., Trautvetter
Subjects: Physics, Experimental Nuclear Physic, Nuclear and High Energy Physics, CNO cycle, S-factor, Underground accelerator, 14N(p, γ)15O, Direct measurement, underground laboratory, γ)15O, Nuclear physics, Cross section (physics), Low energy, 14N(p, National laboratory, Nuclear Astrophysic
Abstract: Deep underground in Gran Sasso National Laboratory (Italy), at the LUNA facility, the cross section of the 14N(p, γ)15O, the slowest process of the CNO cycle, has been measured at energies much lower than achieved before. Using a 400 kV accelerator, a windowless gas target and a 4π BGO summing detector, direct cross section data has been obtained down to 70 keV, reaching a value of 0.24 picobarn, corresponding to an S-factor of 1.74±0.14(stat)±0.14(syst) keV barn. The Gamow peak has been covered by direct experimental data for several scenarios of stable and explosive hydrogen burning. The ωγ strength of the 259 keV resonance has been re-measured obtaining 12.8±0.3(stat)±0.4(syst) meV. The stellar reaction rate has been calculated for temperatures 0.09×109−0.3×109 K. A complete description of the experiment is here presented, including the impact of the present data on nucleosynthesis in AGB stars.
Published: 2006

273. First measurement of the 14N(p,gamma)15O cross section down to 70 keV

Author: Carlo Broggini, Gianluca Imbriani, R. Bonetti, C. Rossi Alvarez, F. Confortola, Oscar Straniero, A. Guglielmetti, Filippo Terrasi, Daniel Bemmerer, Vincenzo Roca, João Cruz, B. Limata, Frank Strieder, Paolo Prati, G. Gervino, H. Costantini, P. Corvisiero, A. Formicola, A. P. Jesus, Zs. Fülöp, E. Somorjai, Gy. Gyürky, C. Rolfs, Detlef Rogalla, F. Schümann, C. Gustavino, Roberto Menegazzo, H. P. Trautvetter, M. Junker, Mario R. Romano, A. Lemut, A., Lemut, D., Bemmerer, F., Confortola, R., Bonetti, C., Broggini, Corvisiero, _. P., H., Costantini, J., Cruz, A., Formicola, Fulop, Z. s., G., Gervino, A., Guglielmetti, C., Gustavino, Gyurky, G. y., Imbriani, Gianluca, A. P., Jesu, M., Junker, B., Limata, R., Menegazzo, P., Prati, Roca, Vincenzo, D., Rogalla, C., Rolf, Romano, Mario, C., Rossi Alvarez, F., Shumann, E., Somorjai, O., Straniero, F., Strieder, and F., Terrasi
Subjects: Nuclear and High Energy Physics, CNO cycle, Explosive material, Hydrogen, Cross section measurement, 14N(p, γ)15O, AGB stars, Hydrogen shell burning, Radiative capture, Underground nuclear astrophysics, Thermonuclear reaction, chemistry.chemical_element, FOS: Physical sciences, Astrophysics, Resonance (particle physics), γ)15O, Nuclear physics, Cross section (physics), 14N(p, Nuclear Experiment (nucl-ex), Nuclear Experiment, Physics, Detector, Astrophysics (astro-ph), Stars, chemistry, Atomic physics
Abstract: In stars with temperatures above 20 × 10 6 K , hydrogen burning is dominated by the CNO cycle. Its rate is determined by the slowest process, the 14N(p, γ)15O reaction. Deep underground in Italy's Gran Sasso laboratory, at the LUNA 400 kV accelerator, the cross section of this reaction has been measured at energies much lower than ever achieved before. Using a windowless gas target and a 4π BGO summing detector, direct cross section data has been obtained down to 70 keV, reaching a value of 0.24 picobarn. The Gamow peak has been covered by experimental data for several scenarios of stable and explosive hydrogen burning. In addition, the strength of the 259 keV resonance has been remeasured. The thermonuclear reaction rate has been calculated for temperatures 90 – 300 × 10 6 K , for the first time with negligible impact from extrapolations.
Published: 2006
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274. Production of new neutron-rich nuclei in projectile fragmentation reactions

Author: Benlliure, J., Casarejos, E., Fernandez, M., Kurtukian Nieto, T., Audouin, L., Becker, F., Giovinazzo, J., Henzlova, D., Henzl, V., Jurado, B., Kelic, A., Napolitani, P., Pereira, J., Rejmund, F., Ricciardi, M.V., Schmidt, K.-H., Yordanov, O., G. Cuttone, A. Gadea, M. Lattuada, S. Lunardi, R. Menegazzo, D. Pierroutsakou, C. Signorini, F. Soramel, L. Tecchio, A. Vitturi, 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), Helmholtz zentrum für Schwerionenforschung GmbH (GSI), 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), 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 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: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Abstract: Communication avec l'équipe de recherche NEX du CENBG; International audience
Published: 2006

275. Feasibility of low energy radiative capture experiments at the LUNA underground accelerator facility

Author: Gianluca Imbriani, Mario R. Romano, Daniel Bemmerer, Matthias Junker, Gy. Gyürky, Roberto Menegazzo, F. Confortola, A. P. Jesus, C. Rossi Alvarez, E. Somorjai, Oscar Straniero, C. Gustavino, C. Rolfs, H. P. Trautvetter, Filippo Terrasi, P. Corvisiero, João Cruz, F. Schümann, A. Guglielmetti, Paolo Prati, A. Lemut, G. Gervino, Detlef Rogalla, A. Formicola, B. Limata, Zs. Fülöp, R. Bonetti, Alberto Vomiero, H. Costantini, C. Broggini, Vincenzo Roca, F. Strieder, D., Bemmerer, F., Confortola, A., Lemut, R., Bonetti, C., Broggini, P., Corvisiero, H., Costantini, J., Cruz, A., Formicola, Flp, Z. S., G., Gervino, A., Guglielmetti, C., Gustavino, Gyrky, G. Y., G., Imbriani, A. P., Jesu, M., Junker, B., Limata, R., Menegazzo, P., Prati, V., Roca, D., Rogalla, C., Rolf, M., Romano, C., ROSSI ALVAREZ, F., Schmann, E., Somorjai, O., Straniero, F., Strieder, Terrasi, Filippo, H. P., Trautvetter, A., Vomiero, Fülöp, Z. s., Gyürky, G. y., Imbriani, Gianluca, Roca, Vincenzo, Romano, Mario, C., Rossi Alvarez, F., Schümann, F., Terrasi, Fulop, Z. S., Gyurky, G. Y., F., Schumann, and AND A., Vomiero
Subjects: Nuclear reaction, Physics, Experimental Nuclear Physic, Nuclear and High Energy Physics, Proton, Gamma ray, chemistry.chemical_element, FOS: Physical sciences, Germanium, Bismuth germanate, underground laboratory, Nuclear physics, symbols.namesake, chemistry.chemical_compound, chemistry, symbols, Nuclear astrophysics, Nuclear Experiment (nucl-ex), Nuclear Astrophysic, Doppler effect, Nuclear Experiment, Beam (structure)
Abstract: The LUNA (Laboratory Underground for Nuclear Astrophysics) facility has been designed to study nuclear reactions of astrophysical interest. It is located deep underground in the Gran Sasso National Laboratory, Italy. Two electrostatic accelerators, with 50 and 400 kV maximum voltage, in combination with solid and gas target setups allowed to measure the total cross sections of the radiative capture reactions $^2$H(p,$\gamma$)3He and $^{14}$N(p,$\gamma$)$^{15}$O within their relevant Gamow peaks. We report on the gamma background in the Gran Sasso laboratory measured by germanium and bismuth germanate detectors, with and without an incident proton beam. A method to localize the sources of beam induced background using the Doppler shift of emitted gamma rays is presented. The feasibility of radiative capture studies at energies of astrophysical interest is discussed for several experimental scenarios., Comment: Submitted to Eur. Phys. J. A
Published: 2005

276. First Direct Measurement of the 64.5 keV Resonance Strength in the ^{17}O(p,γ)^{18}F Reaction.

Author: Gesuè RM, Ciani GF, Piatti D, Boeltzig A, Rapagnani D, Aliotta M, Ananna C, Barbieri L, Barile F, Bemmerer D, Best A, Broggini C, Bruno CG, Caciolli A, Campostrini M, Casaburo F, Cavanna F, Colombetti P, Compagnucci A, Corvisiero P, Csedreki L, Davinson T, De Gregorio GM, Dell'Aquila D, Depalo R, Di Leva A, Elekes Z, Ferraro F, Formicola A, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Lugaro M, Marigo P, Marsh J, Masha E, Menegazzo R, Mercogliano D, Paticchio V, Perrino R, Prati P, Rigato V, Robb D, Schiavulli L, Sidhu RS, Skowronski J, Straniero O, Szücs T, and Zavatarelli S
Abstract: The CNO cycle is one of the most important nuclear energy sources in stars. At temperatures of hydrostatic H-burning (20 MK
Published: 2024
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277. High-Precision Spectroscopy of ^{20}O Benchmarking Ab Initio Calculations in Light Nuclei.

Author: Zanon I, Clément E, Goasduff A, Menéndez J, Miyagi T, Assié M, Ciemała M, Flavigny F, Lemasson A, Matta A, Ramos D, Rejmund M, Achouri L, Ackermann D, Barrientos D, Beaumel D, Benzoni G, Boston AJ, Boston HC, Bottoni S, Bracco A, Brugnara D, de France G, de Sereville N, Delaunay F, Desesquelles P, Didierjean F, Domingo-Prato C, Dudouet J, Eberth J, Fernández D, Fougères C, Gadea A, Galtarossa F, Girard-Alcindor V, Gonzales V, Gottardo A, Hammache F, Harkness-Brennan LJ, Hess H, Judson DS, Jungclaus A, Kaşkaş A, Kim YH, Kuşoğlu A, Labiche M, Leblond S, Lenain C, Lenzi SM, Leoni S, Li H, Ljungvall J, Lois-Fuentes J, Lopez-Martens A, Maj A, Menegazzo R, Mengoni D, Michelagnoli C, Million B, Napoli DR, Nyberg J, Pasqualato G, Podolyak Z, Pullia A, Quintana B, Recchia F, Regueira-Castro D, Reiter P, Rezynkina K, Rojo JS, Salsac MD, Sanchis E, Şenyiğit M, Siciliano M, Sohler D, Stezowski O, Theisen C, Utepov A, Valiente-Dobón JJ, Verney D, and Zielinska M
Abstract: The excited states of unstable ^{20}O were investigated via γ-ray spectroscopy following the ^{19}O(d,p)^{20}O reaction at 8 AMeV. By exploiting the Doppler shift attenuation method, the lifetimes of the 2_{2}^{+} and 3_{1}^{+} states were firmly established. From the γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+} and 3_{1}^{+} states, the B(E2) and B(M1) were determined. Various chiral effective field theory Hamiltonians, describing the nuclear properties beyond ground states, along with a standard USDB interaction, were compared with the experimentally obtained data. Such a comparison for a large set of γ-ray transition probabilities with the valence space in medium similarity renormalization group ab initio calculations was performed for the first time in a nucleus far from stability. It was shown that the ab initio approaches using chiral effective field theory forces are challenged by detailed high-precision spectroscopic properties of nuclei. The reduced transition probabilities were found to be a very constraining test of the performance of the ab initio models.
Published: 2023
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278. Proton-Capture Rates on Carbon Isotopes and Their Impact on the Astrophysical ^{12}C/^{13}C Ratio.

Author: Skowronski J, Boeltzig A, Ciani GF, Csedreki L, Piatti D, Aliotta M, Ananna C, Barile F, Bemmerer D, Best A, Broggini C, Bruno CG, Caciolli A, Campostrini M, Cavanna F, Colombetti P, Compagnucci A, Corvisiero P, Davinson T, Depalo R, Di Leva A, Elekes Z, Ferraro F, Formicola A, Fülöp Z, Gervino G, Gesuè RM, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Lugaro M, Marigo P, Masha E, Menegazzo R, Paticchio V, Perrino R, Prati P, Rapagnani D, Rigato V, Schiavulli L, Sidhu RS, Straniero O, Szücs T, and Zavatarelli S
Abstract: The ^{12}C/^{13}C ratio is a significant indicator of nucleosynthesis and mixing processes during hydrogen burning in stars. Its value mainly depends on the relative rates of the ^{12}C(p,γ)^{13}N and ^{13}C(p,γ)^{14}N reactions. Both reactions have been studied at the Laboratory for Underground Nuclear Astrophysics (LUNA) in Italy down to the lowest energies to date (E_{c.m.}=60 keV) reaching for the first time the high energy tail of hydrogen burning in the shell of giant stars. Our cross sections, obtained with both prompt γ-ray detection and activation measurements, are the most precise to date with overall systematic uncertainties of 7%-8%. Compared with most of the literature, our results are systematically lower, by 25% for the ^{12}C(p,γ)^{13}N reaction and by 30% for ^{13}C(p,γ)^{14}N. We provide the most precise value up to now of 3.6±0.4 in the 20-140 MK range for the lowest possible ^{12}C/^{13}C ratio that can be produced during H burning in giant stars.
Published: 2023
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279. Search for 22 Na in novae supported by a novel method for measuring femtosecond nuclear lifetimes.

Author: Fougères C, de Oliveira Santos F, José J, Michelagnoli C, Clément E, Kim YH, Lemasson A, Guimarães V, Barrientos D, Bemmerer D, Benzoni G, Boston AJ, Böttger R, Boulay F, Bracco A, Čeliković I, Cederwall B, Ciemala M, Delafosse C, Domingo-Pardo C, Dudouet J, Eberth J, Fülöp Z, González V, Gottardo A, Goupil J, Hess H, Jungclaus A, Kaşkaş A, Korichi A, Lenzi SM, Leoni S, Li H, Ljungvall J, Lopez-Martens A, Menegazzo R, Mengoni D, Million B, Mrázek J, Napoli DR, Navin A, Nyberg J, Podolyák Z, Pullia A, Quintana B, Ralet D, Redon N, Reiter P, Rezynkina K, Saillant F, Salsac MD, Sánchez-Benítez AM, Sanchis E, Şenyiğit M, Siciliano M, Smirnova NA, Sohler D, Stanoiu M, Theisen C, Valiente-Dobón JJ, Ujić P, and Zielińska M
Abstract: Classical novae are thermonuclear explosions in stellar binary systems, and important sources of 26 Al and 22 Na. While γ rays from the decay of the former radioisotope have been observed throughout the Galaxy, 22 Na remains untraceable. Its half-life (2.6 yr) would allow the observation of its 1.275 MeV γ-ray line from a cosmic source. However, the prediction of such an observation requires good knowledge of its nucleosynthesis. The 22 Na(p, γ) 23 Mg reaction remains the only source of large uncertainty about the amount of 22 Na ejected. Its rate is dominated by a single resonance on the short-lived state at 7785.0(7) keV in 23 Mg. Here, we propose a combined analysis of particle-particle correlations and velocity-difference profiles to measure femtosecond nuclear lifetimes. The application of this method to the study of the 23 Mg states, places strong limits on the amount of 22 Na produced in novae and constrains its detectability with future space-borne observatories., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)
Published: 2023
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280. Evidence of Partial Seniority Conservation in the πg_{9/2} Shell for the N=50 Isotones.

Author: Pérez-Vidal RM, Gadea A, Domingo-Pardo C, Gargano A, Valiente-Dobón JJ, Clément E, Lemasson A, Coraggio L, Siciliano M, Szilner S, Bast M, Braunroth T, Collado J, Corina A, Dewald A, Doncel M, Dudouet J, de France G, Fransen C, González V, Hüyük T, Jacquot B, John PR, Jungclaus A, Kim YH, Korichi A, Labiche M, Lenzi S, Li H, Ljungvall J, López-Martens A, Mengoni D, Michelagnoli C, Müller-Gatermann C, Napoli DR, Navin A, Quintana B, Ramos D, Rejmund M, Sanchis E, Simpson J, Stezowski O, Wilmsen D, Zielińska M, Boston AJ, Barrientos D, Bednarczyk P, Benzoni G, Birkenbach B, Boston HC, Bracco A, Cederwall B, Cullen DM, Didierjean F, Eberth J, Gottardo A, Goupil J, Harkness-Brennan LJ, Hess H, Judson DS, Kaşkaş A, Korten W, Leoni S, Menegazzo R, Million B, Nyberg J, Podolyak Z, Pullia A, Ralet D, Recchia F, Reiter P, Rezynkina K, Salsac MD, Şenyiğit M, Sohler D, Theisen C, and Verney D
Abstract: The reduced transition probabilities for the 4_{1}^{+}→2_{1}^{+} and 2_{1}^{+}→0_{1}^{+} transitions in ^{92}Mo and ^{94}Ru and for the 4_{1}^{+}→2_{1}^{+} and 6_{1}^{+}→4_{1}^{+} transitions in ^{90}Zr have been determined in this experiment making use of a multinucleon transfer reaction. These results have been interpreted on the basis of realistic shell-model calculations in the f_{5/2}, p_{3/2}, p_{1/2}, and g_{9/2} proton valence space. Only the combination of extensive lifetime information and large scale shell-model calculations allowed the extent of the seniority conservation in the N=50 g_{9/2} orbital to be understood. The conclusion is that seniority is largely conserved in the first πg_{9/2} orbital.
Published: 2022
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281. Direct Measurement of the ^{13}C(α,n)^{16}O Cross Section into the s-Process Gamow Peak.

Author: Ciani GF, Csedreki L, Rapagnani D, Aliotta M, Balibrea-Correa J, Barile F, Bemmerer D, Best A, Boeltzig A, Broggini C, Bruno CG, Caciolli A, Cavanna F, Chillery T, Colombetti P, Corvisiero P, Cristallo S, Davinson T, Depalo R, Di Leva A, Elekes Z, Ferraro F, Fiore E, Formicola A, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Lugaro M, Marigo P, Masha E, Menegazzo R, Mossa V, Pantaleo FR, Paticchio V, Perrino R, Piatti D, Prati P, Schiavulli L, Stöckel K, Straniero O, Szücs T, Takács MP, Terrasi F, Vescovi D, and Zavatarelli S
Abstract: One of the main neutron sources for the astrophysical s process is the reaction ^{13}C(α,n)^{16}O, taking place in thermally pulsing asymptotic giant branch stars at temperatures around 90 MK. To model the nucleosynthesis during this process the reaction cross section needs to be known in the 150-230 keV energy window (Gamow peak). At these sub-Coulomb energies, cross section direct measurements are severely affected by the low event rate, making us rely on input from indirect methods and extrapolations from higher-energy direct data. This leads to an uncertainty in the cross section at the relevant energies too high to reliably constrain the nuclear physics input to s-process calculations. We present the results from a new deep-underground measurement of ^{13}C(α,n)^{16}O, covering the energy range 230-300 keV, with drastically reduced uncertainties over previous measurements and for the first time providing data directly inside the s-process Gamow peak. Selected stellar models have been computed to estimate the impact of our revised reaction rate. For stars of nearly solar composition, we find sizeable variations of some isotopes, whose production is influenced by the activation of close-by branching points that are sensitive to the neutron density, in particular, the two radioactive nuclei ^{60}Fe and ^{205}Pb, as well as ^{152}Gd.
Published: 2021
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282. The baryon density of the Universe from an improved rate of deuterium burning.

Author: Mossa V, Stöckel K, Cavanna F, Ferraro F, Aliotta M, Barile F, Bemmerer D, Best A, Boeltzig A, Broggini C, Bruno CG, Caciolli A, Chillery T, Ciani GF, Corvisiero P, Csedreki L, Davinson T, Depalo R, Di Leva A, Elekes Z, Fiore EM, Formicola A, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Kievsky A, Kochanek I, Lugaro M, Marcucci LE, Mangano G, Marigo P, Masha E, Menegazzo R, Pantaleo FR, Paticchio V, Perrino R, Piatti D, Pisanti O, Prati P, Schiavulli L, Straniero O, Szücs T, Takács MP, Trezzi D, Viviani M, and Zavatarelli S
Abstract: Light elements were produced in the first few minutes of the Universe through a sequence of nuclear reactions known as Big Bang nucleosynthesis (BBN) 1,2 . Among the light elements produced during BBN 1,2 , deuterium is an excellent indicator of cosmological parameters because its abundance is highly sensitive to the primordial baryon density and also depends on the number of neutrino species permeating the early Universe. Although astronomical observations of primordial deuterium abundance have reached percent accuracy 3 , theoretical predictions 4-6 based on BBN are hampered by large uncertainties on the cross-section of the deuterium burning D(p,γ) 3 He reaction. Here we show that our improved cross-sections of this reaction lead to BBN estimates of the baryon density at the 1.6 percent level, in excellent agreement with a recent analysis of the cosmic microwave background 7 . Improved cross-section data were obtained by exploiting the negligible cosmic-ray background deep underground at the Laboratory for Underground Nuclear Astrophysics (LUNA) of the Laboratori Nazionali del Gran Sasso (Italy) 8,9 . We bombarded a high-purity deuterium gas target 10 with an intense proton beam from the LUNA 400-kilovolt accelerator 11 and detected the γ-rays from the nuclear reaction under study with a high-purity germanium detector. Our experimental results settle the most uncertain nuclear physics input to BBN calculations and substantially improve the reliability of using primordial abundances to probe the physics of the early Universe.
Published: 2020
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283. Isospin Properties of Nuclear Pair Correlations from the Level Structure of the Self-Conjugate Nucleus ^{88}Ru.

Author: Cederwall B, Liu X, Aktas Ö, Ertoprak A, Zhang W, Qi C, Clément E, de France G, Ralet D, Gadea A, Goasduff A, Jaworski G, Kuti I, Nyakó BM, Nyberg J, Palacz M, Wadsworth R, Valiente-Dobón JJ, Al-Azri H, Ataç Nyberg A, Bäck T, de Angelis G, Doncel M, Dudouet J, Gottardo A, Jurado M, Ljungvall J, Mengoni D, Napoli DR, Petrache CM, Sohler D, Timár J, Barrientos D, Bednarczyk P, Benzoni G, Birkenbach B, Boston AJ, Boston HC, Burrows I, Charles L, Ciemala M, Crespi FCL, Cullen DM, Désesquelles P, Domingo-Pardo C, Eberth J, Erduran N, Ertürk S, González V, Goupil J, Hess H, Huyuk T, Jungclaus A, Korten W, Lemasson A, Leoni S, Maj A, Menegazzo R, Million B, Perez-Vidal RM, Podolyak Z, Pullia A, Recchia F, Reiter P, Saillant F, Salsac MD, Sanchis E, Simpson J, Stezowski O, Theisen C, and Zielińska M
Abstract: The low-lying energy spectrum of the extremely neutron-deficient self-conjugate (N=Z) nuclide _{44}^{88}Ru_{44} has been measured using the combination of the Advanced Gamma Tracking Array (AGATA) spectrometer, the NEDA and Neutron Wall neutron detector arrays, and the DIAMANT charged particle detector array. Excited states in ^{88}Ru were populated via the ^{54}Fe(^{36}Ar,2nγ)^{88}Ru^{*} fusion-evaporation reaction at the Grand Accélérateur National d'Ions Lourds (GANIL) accelerator complex. The observed γ-ray cascade is assigned to ^{88}Ru using clean prompt γ-γ-2-neutron coincidences in anticoincidence with the detection of charged particles, confirming and extending the previously assigned sequence of low-lying excited states. It is consistent with a moderately deformed rotating system exhibiting a band crossing at a rotational frequency that is significantly higher than standard theoretical predictions with isovector pairing, as well as observations in neighboring N>Z nuclides. The direct observation of such a "delayed" rotational alignment in a deformed N=Z nucleus is in agreement with theoretical predictions related to the presence of strong isoscalar neutron-proton pair correlations.
Published: 2020
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284. Pseudospin Symmetry and Microscopic Origin of Shape Coexistence in the ^{78}Ni Region: A Hint from Lifetime Measurements.

Author: Delafosse C, Verney D, Marević P, Gottardo A, Michelagnoli C, Lemasson A, Goasduff A, Ljungvall J, Clément E, Korichi A, De Angelis G, Andreoiu C, Babo M, Boso A, Didierjean F, Dudouet J, Franchoo S, Gadea A, Georgiev G, Ibrahim F, Jacquot B, Konstantinopoulos T, Lenzi SM, Maquart G, Matea I, Mengoni D, Napoli DR, Nikšić T, Olivier L, Pérez-Vidal RM, Portail C, Recchia F, Redon N, Siciliano M, Stefan I, Stezowski O, Vretenar D, Zielinska M, Barrientos D, Benzoni G, Birkenbach B, Boston AJ, Boston HC, Cederwall B, Charles L, Ciemala M, Collado J, Cullen DM, Désesquelles P, de France G, Domingo-Pardo C, Eberth J, González V, Harkness-Brennan LJ, Hess H, Judson DS, Jungclaus A, Korten W, Lefevre A, Legruel F, Menegazzo R, Million B, Nyberg J, Quintana B, Ralet D, Reiter P, Saillant F, Sanchis E, Theisen C, and Valiente Dobon JJ
Abstract: Lifetime measurements of excited states of the light N=52 isotones ^{88}Kr, ^{86}Se, and ^{84}Ge have been performed, using the recoil distance Doppler shift method and VAMOS and AGATA spectrometers for particle identification and gamma spectroscopy, respectively. The reduced electric quadrupole transition probabilities B(E2;2^{+}→0^{+}) and B(E2;4^{+}→2^{+}) were obtained for the first time for the hard-to-reach ^{84}Ge. While the B(E2;2^{+}→0^{+}) values of ^{88}Kr, ^{86}Se saturate the maximum quadrupole collectivity offered by the natural valence (3s, 2d, 1g_{7/2}, 1h_{11/2}) space of an inert ^{78}Ni core, the value obtained for ^{84}Ge largely exceeds it, suggesting that shape coexistence phenomena, previously reported at N≲49, extend beyond N=50. The onset of collectivity at Z=32 is understood as due to a pseudo-SU(3) organization of the proton single-particle sequence reflecting a clear manifestation of pseudospin symmetry. It is realized that the latter provides actually reliable guidance for understanding the observed proton and neutron single particle structure in the whole medium-mass region, from Ni to Sn, pointing towards the important role of the isovector-vector ρ field in shell-structure evolution.
Published: 2018
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285. Direct Capture Cross Section and the E_{p}=71 and 105 keV Resonances in the ^{22}Ne(p,γ)^{23}Na Reaction.

Author: Ferraro F, Takács MP, Piatti D, Cavanna F, Depalo R, Aliotta M, Bemmerer D, Best A, Boeltzig A, Broggini C, Bruno CG, Caciolli A, Chillery T, Ciani GF, Corvisiero P, Davinson T, D'Erasmo G, Di Leva A, Elekes Z, Fiore EM, Formicola A, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Karakas A, Kochanek I, Lugaro M, Marigo P, Menegazzo R, Mossa V, Pantaleo FR, Paticchio V, Perrino R, Prati P, Schiavulli L, Stöckel K, Straniero O, Szücs T, Trezzi D, and Zavatarelli S
Abstract: The ^{22}Ne(p,γ)^{23}Na reaction, part of the neon-sodium cycle of hydrogen burning, may explain the observed anticorrelation between sodium and oxygen abundances in globular cluster stars. Its rate is controlled by a number of low-energy resonances and a slowly varying nonresonant component. Three new resonances at E_{p}=156.2, 189.5, and 259.7 keV have recently been observed and confirmed. However, significant uncertainty on the reaction rate remains due to the nonresonant process and to two suggested resonances at E_{p}=71 and 105 keV. Here, new ^{22}Ne(p,γ)^{23}Na data with high statistics and low background are reported. Stringent upper limits of 6×10^{-11} and 7×10^{-11} eV (90% confidence level), respectively, are placed on the two suggested resonances. In addition, the off-resonant S factor has been measured at unprecedented low energy, constraining the contributions from a subthreshold resonance and the direct capture process. As a result, at a temperature of 0.1 GK the error bar of the ^{22}Ne(p,γ)^{23}Na rate is now reduced by 3 orders of magnitude.
Published: 2018
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286. Erratum: Three New Low-Energy Resonances in the ^{22}Ne(p,γ)^{23}Na Reaction [Phys. Rev. Lett. 115, 252501 (2015)].

Author: Cavanna F, Depalo R, Aliotta M, Anders M, Bemmerer D, Best A, Boeltzig A, Broggini C, Bruno CG, Caciolli A, Corvisiero P, Davinson T, di Leva A, Elekes Z, Ferraro F, Formicola A, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Menegazzo R, Mossa V, Pantaleo FR, Prati P, Scott DA, Somorjai E, Straniero O, Strieder F, Szücs T, Takács MP, and Trezzi D
Abstract: This corrects the article DOI: 10.1103/PhysRevLett.115.252501.
Published: 2018
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287. _{36}^{96}Kr_{60}-Low-Z Boundary of the Island of Deformation at N=60.

Author: Dudouet J, Lemasson A, Duchêne G, Rejmund M, Clément E, Michelagnoli C, Didierjean F, Korichi A, Maquart G, Stezowski O, Lizarazo C, Pérez-Vidal RM, Andreoiu C, de Angelis G, Astier A, Delafosse C, Deloncle I, Dombradi Z, de France G, Gadea A, Gottardo A, Jacquot B, Jones P, Konstantinopoulos T, Kuti I, Le Blanc F, Lenzi SM, Li G, Lozeva R, Million B, Napoli DR, Navin A, Petrache CM, Pietralla N, Ralet D, Ramdhane M, Redon N, Schmitt C, Sohler D, Verney D, Barrientos D, Birkenbach B, Burrows I, Charles L, Collado J, Cullen DM, Désesquelles P, Domingo Pardo C, González V, Harkness-Brennan L, Hess H, Judson DS, Karolak M, Korten W, Labiche M, Ljungvall J, Menegazzo R, Mengoni D, Pullia A, Recchia F, Reiter P, Salsac MD, Sanchis E, Theisen C, Valiente-Dobón JJ, and Zielińska M
Abstract: Prompt γ-ray spectroscopy of the neutron-rich ^{96}Kr, produced in transfer- and fusion-induced fission reactions, has been performed using the combination of the Advanced Gamma Tracking Array and the VAMOS++ spectrometer. A second excited state, assigned to J^{π}=4^{+}, is observed for the first time, and a previously reported level energy of the first 2^{+} excited state is confirmed. The measured energy ratio R_{4/2}=E(4^{+})/E(2^{+})=2.12(1) indicates that this nucleus does not show a well-developed collectivity contrary to that seen in heavier N=60 isotones. This new measurement highlights an abrupt transition of the degree of collectivity as a function of the proton number at Z=36, of similar amplitude to that observed at N=60 at higher Z values. A possible reason for this abrupt transition could be related to the insufficient proton excitations in the g_{9/2}, d_{5/2}, and s_{1/2} orbitals to generate strong quadrupole correlations or to the coexistence of competing different shapes. An unexpected continuous decrease of R_{4/2} as a function of the neutron number up to N=60 is also evidenced. This measurement establishes the Kr isotopic chain as the low-Z boundary of the island of deformation for N=60 isotones. A comparison with available theoretical predictions using different beyond mean-field approaches shows that these models fail to reproduce the abrupt transitions at N=60 and Z=36.
Published: 2017
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288. Improved Direct Measurement of the 64.5 keV Resonance Strength in the ^{17}O(p,α)^{14}N Reaction at LUNA.

Author: Bruno CG, Scott DA, Aliotta M, Formicola A, Best A, Boeltzig A, Bemmerer D, Broggini C, Caciolli A, Cavanna F, Ciani GF, Corvisiero P, Davinson T, Depalo R, Di Leva A, Elekes Z, Ferraro F, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Menegazzo R, Mossa V, Pantaleo FR, Piatti D, Prati P, Somorjai E, Straniero O, Strieder F, Szücs T, Takács MP, and Trezzi D
Abstract: The ^{17}O(p,α)^{14}N reaction plays a key role in various astrophysical scenarios, from asymptotic giant branch stars to classical novae. It affects the synthesis of rare isotopes such as ^{17}O and ^{18}F, which can provide constraints on astrophysical models. A new direct determination of the E_{R}=64.5 keV resonance strength performed at the Laboratory for Underground Nuclear Astrophysics (LUNA) accelerator has led to the most accurate value to date ωγ=10.0±1.4_{stat}±0.7_{syst} neV, thanks to a significant background reduction underground and generally improved experimental conditions. The (bare) proton partial width of the corresponding state at E_{x}=5672 keV in ^{18}F is Γ_{p}=35±5_{stat}±3_{syst} neV. This width is about a factor of 2 higher than previously estimated, thus leading to a factor of 2 increase in the ^{17}O(p, α)^{14}N reaction rate at astrophysical temperatures relevant to shell hydrogen burning in red giant and asymptotic giant branch stars. The new rate implies lower ^{17}O/^{16}O ratios, with important implications on the interpretation of astrophysical observables from these stars.
Published: 2016
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289. Superdeformed and Triaxial States in ^{42}Ca.

Author: Hadyńska-Klȩk K, Napiorkowski PJ, Zielińska M, Srebrny J, Maj A, Azaiez F, Valiente Dobón JJ, Kicińska-Habior M, Nowacki F, Naïdja H, Bounthong B, Rodríguez TR, de Angelis G, Abraham T, Anil Kumar G, Bazzacco D, Bellato M, Bortolato D, Bednarczyk P, Benzoni G, Berti L, Birkenbach B, Bruyneel B, Brambilla S, Camera F, Chavas J, Cederwall B, Charles L, Ciemała M, Cocconi P, Coleman-Smith P, Colombo A, Corsi A, Crespi FC, Cullen DM, Czermak A, Désesquelles P, Doherty DT, Dulny B, Eberth J, Farnea E, Fornal B, Franchoo S, Gadea A, Giaz A, Gottardo A, Grave X, Grȩbosz J, Görgen A, Gulmini M, Habermann T, Hess H, Isocrate R, Iwanicki J, Jaworski G, Judson DS, Jungclaus A, Karkour N, Kmiecik M, Karpiński D, Kisieliński M, Kondratyev N, Korichi A, Komorowska M, Kowalczyk M, Korten W, Krzysiek M, Lehaut G, Leoni S, Ljungvall J, Lopez-Martens A, Lunardi S, Maron G, Mazurek K, Menegazzo R, Mengoni D, Merchán E, Mȩczyński W, Michelagnoli C, Mierzejewski J, Million B, Myalski S, Napoli DR, Nicolini R, Niikura M, Obertelli A, Özmen SF, Palacz M, Próchniak L, Pullia A, Quintana B, Rampazzo G, Recchia F, Redon N, Reiter P, Rosso D, Rusek K, Sahin E, Salsac MD, Söderström PA, Stefan I, Stézowski O, Styczeń J, Theisen Ch, Toniolo N, Ur CA, Vandone V, Wadsworth R, Wasilewska B, Wiens A, Wood JL, Wrzosek-Lipska K, and Ziȩbliński M
Abstract: Shape parameters of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in ^{42}Ca were determined from E2 matrix elements measured in the first low-energy Coulomb excitation experiment performed with AGATA. The picture of two coexisting structures is well reproduced by new state-of-the-art large-scale shell model and beyond-mean-field calculations. Experimental evidence for superdeformation of the band built on 0_{2}^{+} has been obtained and the role of triaxiality in the A∼40 mass region is discussed. Furthermore, the potential of Coulomb excitation as a tool to study superdeformation has been demonstrated for the first time.
Published: 2016
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290. Three New Low-Energy Resonances in the ^{22}Ne(p,γ)^{23}Na Reaction.

Author: Cavanna F, Depalo R, Aliotta M, Anders M, Bemmerer D, Best A, Boeltzig A, Broggini C, Bruno CG, Caciolli A, Corvisiero P, Davinson T, di Leva A, Elekes Z, Ferraro F, Formicola A, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Menegazzo R, Mossa V, Pantaleo FR, Prati P, Scott DA, Somorjai E, Straniero O, Strieder F, Szücs T, Takács MP, and Trezzi D
Abstract: The ^{22}Ne(p,γ)^{23}Na reaction takes part in the neon-sodium cycle of hydrogen burning. This cycle affects the synthesis of the elements between ^{20}Ne and ^{27}Al in asymptotic giant branch stars and novae. The ^{22}Ne(p,γ)^{23}Na reaction rate is very uncertain because of a large number of unobserved resonances lying in the Gamow window. At proton energies below 400 keV, only upper limits exist in the literature for the resonance strengths. Previous reaction rate evaluations differ by large factors. In the present work, the first direct observations of the ^{22}Ne(p,γ)^{23}Na resonances at 156.2, 189.5, and 259.7 keV are reported. Their resonance strengths are derived with 2%-7% uncertainty. In addition, upper limits for three other resonances are greatly reduced. Data are taken using a windowless ^{22}Ne gas target and high-purity germanium detectors at the Laboratory for Underground Nuclear Astrophysics in the Gran Sasso laboratory of the National Institute for Nuclear Physics, Italy, taking advantage of the ultralow background observed deep underground. The new reaction rate is a factor of 20 higher than the recent evaluation at a temperature of 0.1 GK, relevant to nucleosynthesis in asymptotic giant branch stars.
Published: 2015
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291. Isospin Mixing in ^{80}Zr: From Finite to Zero Temperature.

Author: Ceruti S, Camera F, Bracco A, Avigo R, Benzoni G, Blasi N, Bocchi G, Bottoni S, Brambilla S, Crespi FC, Giaz A, Leoni S, Mentana A, Million B, Morales AI, Nicolini R, Pellegri L, Pullia A, Riboldi S, Wieland O, Birkenbach B, Bazzacco D, Ciemala M, Désesquelles P, Eberth J, Farnea E, Görgen A, Gottardo A, Hess H, Judson DS, Jungclaus A, Kmiecik M, Korten W, Maj A, Menegazzo R, Mengoni D, Michelagnoli C, Modamio V, Montanari D, Myalski S, Napoli D, Quintana B, Reiter P, Recchia F, Rosso D, Sahin E, Salsac MD, Söderström PA, Stezowski O, Theisen C, Ur C, Valiente-Dobón JJ, and Zieblinski M
Abstract: The isospin mixing was deduced in the compound nucleus ^{80}Zr at an excitation energy of E^{*}=54 MeV from the γ decay of the giant dipole resonance. The reaction ^{40}Ca+^{40}Ca at E_{beam}=136 MeV was used to form the compound nucleus in the isospin I=0 channel, while the reaction ^{37}Cl+^{44}Ca at E_{beam}=95 MeV was used as the reference reaction. The γ rays were detected with the AGATA demonstrator array coupled with LaBr_{3}:Ce detectors. The temperature dependence of the isospin mixing was obtained and the zero-temperature value deduced. The isospin-symmetry-breaking correction δ_{C} used for the Fermi superallowed transitions was extracted and found to be consistent with β-decay data.
Published: 2015
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292. First direct measurement of the 2H(α,γ)6Li cross section at big bang energies and the primordial lithium problem.

Author: Anders M, Trezzi D, Menegazzo R, Aliotta M, Bellini A, Bemmerer D, Broggini C, Caciolli A, Corvisiero P, Costantini H, Davinson T, Elekes Z, Erhard M, Formicola A, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Junker M, Lemut A, Marta M, Mazzocchi C, Prati P, Rossi Alvarez C, Scott DA, Somorjai E, Straniero O, and Szücs T
Abstract: Recent observations of (6)Li in metal poor stars suggest a large production of this isotope during big bang nucleosynthesis (BBN). In standard BBN calculations, the (2)H(α,γ)(6)Li reaction dominates (6)Li production. This reaction has never been measured inside the BBN energy region because its cross section drops exponentially at low energy and because the electric dipole transition is strongly suppressed for the isoscalar particles (2)H and α at energies below the Coulomb barrier. Indirect measurements using the Coulomb dissociation of (6)Li only give upper limits owing to the dominance of nuclear breakup processes. Here, we report on the results of the first measurement of the (2)H(α,γ)(6)Li cross section at big bang energies. The experiment was performed deep underground at the LUNA 400 kV accelerator in Gran Sasso, Italy. The primordial (6)Li/(7)Li isotopic abundance ratio has been determined to be (1.5 ± 0.3) × 10(-5), from our experimental data and standard BBN theory. The much higher (6)Li/(7)Li values reported for halo stars will likely require a nonstandard physics explanation, as discussed in the literature.
Published: 2014
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293. Isospin character of low-lying pygmy dipole states in 208Pb via inelastic scattering of 17O ions.

Author: Crespi FC, Bracco A, Nicolini R, Mengoni D, Pellegri L, Lanza EG, Leoni S, Maj A, Kmiecik M, Avigo R, Benzoni G, Blasi N, Boiano C, Bottoni S, Brambilla S, Camera F, Ceruti S, Giaz A, Million B, Morales AI, Vandone V, Wieland O, Bednarczyk P, Ciemała M, Grebosz J, Krzysiek M, Mazurek K, Zieblinski M, Bazzacco D, Bellato M, Birkenbach B, Bortolato D, Calore E, Cederwall B, Charles L, de Angelis G, Désesquelles P, Eberth J, Farnea E, Gadea A, Görgen A, Gottardo A, Isocrate R, Jolie J, Jungclaus A, Karkour N, Korten W, Menegazzo R, Michelagnoli C, Molini P, Napoli DR, Pullia A, Recchia F, Reiter P, Rosso D, Sahin E, Salsac MD, Siebeck B, Siem S, Simpson J, Söderström PA, Stezowski O, Theisen Ch, Ur C, and Valiente-Dobón JJ
Abstract: The properties of pygmy dipole states in 208Pb were investigated using the 208Pb(17O, 17O'γ) reaction at 340 MeV and measuring the γ decay with high resolution with the AGATA demonstrator array. Cross sections and angular distributions of the emitted γ rays and of the scattered particles were measured. The results are compared with (γ, γ') and (p, p') data. The data analysis with the distorted wave Born approximation approach gives a good description of the elastic scattering and of the inelastic excitation of the 2+ and 3- states. For the dipole transitions a form factor obtained by folding a microscopically calculated transition density was used for the first time. This has allowed us to extract the isoscalar component of the 1- excited states from 4 to 8 MeV.
Published: 2014
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294. First characterisation of natural radioactivity in building materials manufactured in Albania.

Author: Xhixha G, Ahmeti A, Bezzon GP, Bitri M, Broggini C, Buso GP, Caciolli A, Callegari I, Cfarku F, Colonna T, Fiorentini G, Guastaldi E, Mantovani F, Massa G, Menegazzo R, Mou L, Prifti D, Rossi Alvarez C, Sadiraj Kuqi D, Shyti M, Tushe L, Xhixha Kaçeli M, and Zyfi A
Subjects: Albania, Radiation Monitoring, Spectrometry, Gamma, Background Radiation, Construction Materials analysis, Potassium Radioisotopes analysis, Radium analysis, Thorium analysis
Abstract: This study focuses on the radiological characterisation of building materials manufactured in Albania by using a high-resolution gamma-ray spectrometer. The average activity concentrations of (40)K, (226)Ra and (232)Th were, respectively, 644.1±64.2, 33.4 ± 6.4 and 42.2 ± 7.6 Bq kg(-1) in the clay brick samples and 179.7 ± 48.9, 55.0 ± 5.8 and 17.0 ± 3.3 Bq kg(-1) in the cement samples. The calculated activity concentration index (ACI), varied from 0.48±0.02 to 0.63±0.04 in the clay brick samples and from 0.29±0.03 to 0.37±0.02 in the cement samples. Based on the ACI, all of the clay brick and cement samples were categorised as A1 materials. The authors can exclude (at 3σ level) any restriction of their use as bulk materials.
Published: 2013
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295. First direct measurement of the 17O(p,γ)18F reaction cross section at Gamow energies for classical novae.

Author: Scott DA, Caciolli A, Di Leva A, Formicola A, Aliotta M, Anders M, Bemmerer D, Broggini C, Campeggio M, Corvisiero P, Elekes Z, Fülöp Z, Gervino G, Guglielmetti A, Gustavino C, Gyürky G, Imbriani G, Junker M, Laubenstein M, Menegazzo R, Marta M, Napolitani E, Prati P, Rigato V, Roca V, Somorjai E, Salvo C, Straniero O, Strieder F, Szücs T, Terrasi F, and Trezzi D
Abstract: Classical novae are important contributors to the abundances of key isotopes, such as the radioactive (18)F, whose observation by satellite missions could provide constraints on nucleosynthesis models in novae. The (17)O(p,γ)(18)F reaction plays a critical role in the synthesis of both oxygen and fluorine isotopes, but its reaction rate is not well determined because of the lack of experimental data at energies relevant to novae explosions. In this study, the reaction cross section has been measured directly for the first time in a wide energy range E(c.m.)~/= 200-370 keV appropriate to hydrogen burning in classical novae. In addition, the E(c.m.)=183 keV resonance strength, ωγ=1.67±0.12 μeV, has been measured with the highest precision to date. The uncertainty on the (17)O(p,γ)(18)F reaction rate has been reduced by a factor of 4, thus leading to firmer constraints on accurate models of novae nucleosynthesis.
Published: 2012
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296. New isomers in the full seniority scheme of neutron-rich lead isotopes: the role of effective three-body forces.

Author: Gottardo A, Valiente-Dobón JJ, Benzoni G, Nicolini R, Gadea A, Lunardi S, Boutachkov P, Bruce AM, Górska M, Grebosz J, Pietri S, Podolyák Z, Pfützner M, Regan PH, Weick H, Alcántara Núñez J, Algora A, Al-Dahan N, de Angelis G, Ayyad Y, Alkhomashi N, Allegro PR, Bazzacco D, Benlliure J, Bowry M, Bracco A, Bunce M, Camera F, Casarejos E, Cortes ML, Crespi FC, Corsi A, Denis Bacelar AM, Deo AY, Domingo-Pardo C, Doncel M, Dombradi Z, Engert T, Eppinger K, Farrelly GF, Farinon F, Farnea E, Geissel H, Gerl J, Goel N, Gregor E, Habermann T, Hoischen R, Janik R, Klupp S, Kojouharov I, Kurz N, Lenzi SM, Leoni S, Mandal S, Menegazzo R, Mengoni D, Million B, Morales AI, Napoli DR, Naqvi F, Nociforo C, Prochazka A, Prokopowicz W, Recchia F, Ribas RV, Reed MW, Rudolph D, Sahin E, Schaffner H, Sharma A, Sitar B, Siwal D, Steiger K, Strmen P, Swan TP, Szarka I, Ur CA, Walker PM, Wieland O, Wollersheim HJ, Nowacki F, Maglione E, and Zuker AP
Abstract: The neutron-rich lead isotopes, up to (216)Pb, have been studied for the first time, exploiting the fragmentation of a primary uranium beam at the FRS-RISING setup at GSI. The observed isomeric states exhibit electromagnetic transition strengths which deviate from state-of-the-art shell-model calculations. It is shown that their complete description demands the introduction of effective three-body interactions and two-body transition operators in the conventional neutron valence space beyond (208)Pb.
Published: 2012
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297. A new FSA approach for in situ γ ray spectroscopy.

Author: Caciolli A, Baldoncini M, Bezzon GP, Broggini C, Buso GP, Callegari I, Colonna T, Fiorentini G, Guastaldi E, Mantovani F, Massa G, Menegazzo R, Mou L, Alvarez CR, Shyti M, Zanon A, and Xhixha G
Subjects: Algorithms, Calibration, Italy, Least-Squares Analysis, Scintillation Counting, Sodium Iodide, Gamma Rays, Radioisotopes analysis, Spectrum Analysis instrumentation, Spectrum Analysis methods
Abstract: An increasing demand of environmental radioactivity monitoring comes both from the scientific community and from the society. This requires accurate, reliable and fast response preferably from portable radiation detectors. Thanks to recent improvements in the technology, γ spectroscopy with sodium iodide scintillators has been proved to be an excellent tool for in-situ measurements for the identification and quantitative determination of γ ray emitting radioisotopes, reducing time and costs. Both for geological and civil purposes not only (40)K, (238)U, and (232)Th have to be measured, but there is also a growing interest to determine the abundances of anthropic elements, like (137)Cs and (131)I, which are used to monitor the effect of nuclear accidents or other human activities. The Full Spectrum Analysis (FSA) approach has been chosen to analyze the γ spectra. The Non Negative Least Square (NNLS) and the energy calibration adjustment have been implemented in this method for the first time in order to correct the intrinsic problem related with the χ(2) minimization which could lead to artifacts and non physical results in the analysis. A new calibration procedure has been developed for the FSA method by using in situ γ spectra instead of calibration pad spectra. Finally, the new method has been validated by acquiring γ spectra with a 10.16 cm × 10.16 cm sodium iodide detector in 80 different sites in the Ombrone basin, in Tuscany. The results from the FSA method have been compared with the laboratory measurements by using HPGe detectors on soil samples collected particular, the (137)Cs isotopes has been implemented in the analysis since it has been found not negligible during the in-situ measurements., (Copyright © 2011 Elsevier B.V. All rights reserved.)
Published: 2012
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298. Lifetime measurements of the neutron-rich N = 30 isotones 50Ca and 51Sc: orbital dependence of effective charges in the fp shell.

Author: Valiente-Dobón JJ, Mengoni D, Gadea A, Farnea E, Lenzi SM, Lunardi S, Dewald A, Pissulla T, Szilner S, Broda R, Recchia F, Algora A, Angus L, Bazzacco D, Benzoni G, Bizzeti PG, Bizzeti-Sona AM, Boutachkov P, Corradi L, Crespi F, de Angelis G, Fioretto E, Görgen A, Gorska M, Gottardo A, Grodner E, Guiot B, Howard A, Królas W, Leoni S, Mason P, Menegazzo R, Montanari D, Montagnoli G, Napoli DR, Obertelli A, Pawłat T, Pollarolo G, Rubio B, Sahin E, Scarlassara F, Silvestri R, Stefanini AM, Smith JF, Steppenbeck D, Ur CA, Wady PT, Wrzesiński J, Maglione E, and Hamamoto I
Abstract: The lifetimes of the first excited states of the N = 30 isotones (50)Ca and (51)Sc have been determined using the Recoil Distance Doppler Shift method in combination with the CLARA-PRISMA spectrometers. This is the first time such a method is applied to measure lifetimes of neutron-rich nuclei populated via a multinucleon transfer reaction. This extends the lifetime knowledge beyond the f_{7/2} shell closure and allows us to derive the effective proton and neutron charges in the fp shell near the doubly magic nucleus (48)Ca, using large-scale, shell-model calculations. These results indicate an orbital dependence of the core polarization along the fp shell.
Published: 2009
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299. Shape coexistence in light se isotopes: evidence for oblate shapes.

Author: Ljungvall J, Görgen A, Girod M, Delaroche JP, Dewald A, Dossat C, Farnea E, Korten W, Melon B, Menegazzo R, Obertelli A, Orlandi R, Petkov P, Pissulla T, Siem S, Singh RP, Srebrny J, Theisen CH, Ur CA, Valiente-Dobón JJ, Zell KO, and Zielińska M
Abstract: Lifetimes of states in the ground-state bands of (70)Se and (72)Se were measured using the recoil-distance Doppler shift method. The results deviate significantly from earlier measurements, requiring a revision of the conclusions drawn from a recent Coulomb excitation experiment concerning the shape of (70)Se. The new results lead to a coherent picture of shape coexistence in the neutron-deficient selenium and krypton isotopes. The coexistence and evolution of oblate and prolate shapes in this mass region is for the first time consistently described by new Hartree-Fock-Bogolyubov-based configuration-mixing calculations which were performed using the Gogny D1S interaction.
Published: 2008
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300. Observation of 54Ni: cross-conjugate symmetry in f7/2 mirror energy differences.

Author: Gadea A, Lenzi SM, Lunardi S, Mărginean N, Zuker AP, de Angelis G, Axiotis M, Martínez T, Napoli DR, Farnea E, Menegazzo R, Pavan P, Ur CA, Bazzacco D, Venturelli R, Kleinheinz P, Bednarczyk P, Curien D, Dorvaux O, Nyberg J, Grawe H, Górska M, Palacz M, Lagergren K, Milechina L, Ekman J, Rudolph D, Andreoiu C, Bentley MA, Gelletly W, Rubio B, Algora A, Nacher E, Caballero L, Trotta M, and Moszyński M
Abstract: Gamma decays from excited states up to Jpi=6+ in the N=Z-2 nucleus 54Ni have been identified for the first time. Level energies are compared with those of the isobars 54Co and 54Fe and of the cross-conjugate nuclei of mass A=42. The good but puzzling f7/ cross-conjugate symmetry in mirror and triplet energy differences is analyzed. Shell model calculations reproduce the new data but the necessary nuclear charge-dependent phenomenology is not fully explained by modern nucleon-nucleon potentials.
Published: 2006
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