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1. PROBING PRE-FORMED ALPHA PARTICLES IN THE GROUND STATE OF NUCLEI

Author

J. A. Scarpaci, M. Fallot, Denis Lacroix, J.L. Laville, A. Chbihi, D. Beaumel, J.D. Frankland, E. Plagnol, Ph. Chomaz, J.C. Roynette, P. Roussel-Chomaz, M. Assié, P. Désesquelle, Y. Blumenfeld, C. Bhar, T. Zerguerras, H. Idbarkach, Elias Khan, A. Shrivastava, E. C. Pollacco, N. Frascaria, L. Lefebvre, 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), 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), CSNSM SNO, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Département d'Electronique, des Détecteurs et d'Informatique pour la Physique (ex SEDI) (DEDIP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire SUBATECH Nantes (SUBATECH), Mines Nantes (Mines Nantes)-Université de Nantes (UN)-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)-Université Paris-Saclay, APC - Cosmologie, Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-AstroParticule et Cosmologie (APC (UMR_7164)), 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)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), CEA/DSM Centre de Saclay (CEA/DSM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Nantes (UN)-Mines Nantes (Mines Nantes), 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), AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-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)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-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)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Nuclear Theory, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, FOS: Physical sciences, General Physics and Astronomy, Alpha particle, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear Theory (nucl-th), Angular distribution, medicine.anatomical_structure, Helium-4, 0103 physical sciences, medicine, Alpha decay, Nuclear Experiment (nucl-ex), Atomic physics, Nuclear Experiment, 010306 general physics, Ground state, Nucleus
Abstract

In this Letter, we report on alpha particle emission through the nuclear break-up in the reaction 40Ca on a 40Ca target at 50A MeV. It is observed that, similarly to nucleons, alpha particles can be emitted to the continuum with very specific angular distribution during the reaction. The alpha particle properties can be understood as resulting from an alpha cluster in the daughter nucleus that is perturbed by the short range nuclear attraction of the collision partner and emitted. A time-dependent theory that describe the alpha particle wave-function evolution is able to reproduce qualitatively the observed angular distribution. This mechanism offers new possibilities to study alpha particle properties in the nuclear medium., Comment: 4 pages, 3 figures

Published
2011
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2. AnomalousE1andE2strengths in40Caand48Caat low excitation energy: A comparative study

Author

A. Gillibert, W. Mittig, F. Auger, J.A. Scarpaci, B. Castel, J.C. Roynette, N. Alamanos, C. Jouanne, N. Frascaria, V. Chiste, F. Marie, V. Lapoux, S. Ottini-Hustache, and Y. Blumenfeld

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Resonance, Order (ring theory), Coulomb excitation, 01 natural sciences, Spectral line, 0103 physical sciences, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon, Excitation, Energy (signal processing)
Abstract

We present the results of an experimental comparative study of the ${}^{40,48}\mathrm{Ca}$ resonance spectra between 6 and 12 MeV. The power of the heavy ion reaction ${}^{40,48}\mathrm{Ca}{(}^{86}\mathrm{Kr},{ }^{86}{\mathrm{Kr}}^{\ensuremath{'}}{)}^{40,48}{\mathrm{Ca}}^{*}$ at 60 MeV per nucleon was exploited to enhance greatly the low energy part of inclusive spectra in order to look for the possible presence of a low energy dipole mode in ${}^{48}\mathrm{Ca}$ due to a neutron skin. We did not observe any difference in the $l=1$ channel and therefore found no evidence of this mode. In the $l=2$ channel, an important excess of strength was observed in ${}^{40}\mathrm{Ca}$ compared to ${}^{48}\mathrm{Ca}$.

Published
1999
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3. Impact parameter dependence of linear momentum transfer and the role of two-body dissipation mechanisms in heavy ion collisions around the Fermi energy

Author

R. Coniglione, C. Agodi, G. Bellia, Y. Blumenfeld, R. Alba, Paolo Piattelli, T. Suomijärvi, Paolo Finocchiaro, K. Loukachine, N. Frascaria, A. Del Zoppo, J.H. Le Faou, F. Auger, Paolo Sapienza, Domenico Santonocito, N. Alamanos, Maria Colonna, J.A. Scarpaci, Ph. Chomaz, A. Gillibert, J.C. Roynette, E. Migneco, C. Maiolino, 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), 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), Robert, Suzanne, and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear and High Energy Physics, High energy, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], 010308 nuclear & particles physics, Nuclear Theory, Fermi energy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Dissipation, 01 natural sciences, 7. Clean energy, Coincidence, Nuclear physics, 0103 physical sciences, Transfer mechanism, Heavy ion, Impact parameter, Atomic physics, Multiplicity (chemistry), Nuclear Experiment, 010306 general physics
Abstract

High energy γ -rays ( E γ >35 MeV) have been measured in coincidence with heavy residues emitted in reactions induced by a 37 MeV/u 36 Ar beam on a 98 Mo target. The γ -ray yield increases strongly with increasing linear momentum transfer indicating the importance of two-body collisions in the transfer mechanism. The high energy γ -ray multiplicity has been used to correlate the linear momentum transfer to the impact parameter. This correlation is compared to dynamical BNV simulations to show the essential role of two body nucleon-nucleon collisions at these bombarding energies.

Published
1998
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4. A new phenomenon in heavy ion inelastic scattering: the towing mode

Author

J.A. Scarpaci, A. van der Woude, N. Frascaria, T. Suomijärvi, J.C. Roynette, F. Maréchal, D. Beaumel, Ph. Chomaz, V. Pascalon-Rozier, I. Lhenry, J.R. Jongman, Y. Blumenfeld, H. Laurent, Denis Lacroix, P. Roussel-Chomaz, Research unit Nuclear & Hadron Physics, 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), 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), Physique théorique, 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)-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)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Nuclear Theory, Mode (statistics), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Inelastic scattering, Deep inelastic scattering, 01 natural sciences, Inelastic neutron scattering, Spectral line, Coincidence, Nuclear physics, 0103 physical sciences, SPECTRA, Atomic physics, 010306 general physics, Nucleon, DECAY, Excitation
Abstract

The inelastic scattering of Ar-40 on Ni-58 has been studied at 44 MeV per nucleon incident energy in coincidence with light particle emission. Besides the well known mechanisms of inelastic excitation, pick up break up and nucleon knock out, a new phenomenon has been observed, giving rise to fast forward moving particles with specific angular correlations. This newly observed mechanism seems to be a generic phenomenon present for various projectile-target combinations and incident energies. Its contribution to the inelastic spectrum has been extracted and a tentative interpretation is given. (C) 1998 Elsevier Science B.V. All rights reserved.

Published
1998
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5. Proton emission in inelastic scattering of40Ca on40Ca at 50 MeV/nucleon

Author

A. van der Woude, J.C. Roynette, I. Lhenry, D. Beaumel, T. Suomijärvi, M. Lamehi-Rachti, J.A. Scarpaci, J.P. Garron, Ph. Chomaz, A. Gillibert, N. Frascaria, N. Alamanos, and Y. Blumenfeld

Subjects
Physics, Nuclear and High Energy Physics, Decay scheme, 010308 nuclear & particles physics, Nuclear Theory, Inelastic scattering, 01 natural sciences, 7. Clean energy, Resonance (particle physics), Charged particle, Nuclear physics, Giant resonance, 0103 physical sciences, Quadrupole, Proton emission, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon
Abstract

Inelastic scattering of {sup 40}Ca on {sup 40}Ca at 50 MeV/nucleon has been measured in coincidence with light charged particles detected over a large angular domain. The giant resonance region of the inelastic spectrum is shown to be dominated by the isoscalar giant quadrupole resonance. The characteristics of the emitted protons allow us to separate four reaction mechanisms contributing to the high excitation energy region of the inelastic spectrum (E{sup {asterisk}}{gt} 30 MeV): pickup breakup, knockout, inelastic scattering to high-lying target states, and a new mechanism responsible for the emission of fast-moving protons. A sizable direct decay branch towards hole states of {sup 39}K is measured for the giant quadrupole resonance in {sup 40}Ca. Evidence is given for the excitation of the two-phonon giant quadrupole resonance, characterized by its direct decay scheme. The energy and width of this two-phonon state are in agreement with a harmonic picture for collective nuclear excitations. {copyright} {ital 1997} {ital The American Physical Society}

Published
1997
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6. Role of the breakup process in theCa48(20Ne,19Nen) reaction at 48AMeV

Author

T. Suomijärvi, [No Value] Lhenry, J.C. Roynette, J. A. Scarpaci, Sydney Gales, P. Roussel-Chomaz, J.P. Garron, A Vanderwoude, H. Laurent, Didier Beaumel, A. Gillibert, J.M. Maison, Jérôme Guillot, Y. Blumenfeld, S. Fortier, and N. Frascaria

Subjects
Physics, Elastic scattering, Nuclear and High Energy Physics, Nuclear Theory, Neutron multiplicity, Breakup, Spectral line, Nuclear physics, Neutron, Atomic physics, Multiplicity (chemistry), Nuclear Experiment, Ground state, Excitation
Abstract

A study of the reaction {sup 48}Ca({sup 20}Ne,{sup 19}Ne {ital n}) at 48{ital A} MeV has been performed at the GANIL facility. The inclusive excitation spectrum above 12 MeV excitation is dominated by a broad structureless bump. Calculations performed in the framework of the Bonaccorso-Brink model predict that the absorption process (transfer+inelastic breakup) dominates over the elastic breakup process. Comparison of the neutron multiplicity calculated in a statistical model with the measured one confirms a significant contribution of the direct processes (elastic and inelastic breakup). The neutron yield to the ground state of the {sup 48}Ca is maximal in the forward direction. Comparisons with calculated neutron angular distributions show the effect of the final state interaction.

Published
1995
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7. The Giant Dipole Resonance at very high temperatures

Author

J.C. Roynette, Ph. Chomaz, K. Loukachine, T. Suomijärvi, G. V. Russo, Paolo Piattelli, N. Frascaria, J.H. Le Faou, A. Del Zoppo, A. Gillibert, E. Migneco, J.P. Garron, G. Bellia, Paolo Finocchiaro, Domenico Santonocito, C. Agodi, F. Auger, C. Maiolino, J.A. Scarpaci, J. J. Gaardhøje, R. Liguori-Neto, R. Alba, Paolo Sapienza, N. Alamanos, R. Coniglione, S. Montironi, Augusto Smerzi, M. Lamehi-Rachti, Y. Blumenfeld, 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), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Evaporation, Resonance, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Dipole, Yield (chemistry), 0103 physical sciences, Physics::Accelerator Physics, Astrophysics::Solar and Stellar Astrophysics, Atomic physics, Nuclear Experiment, 010306 general physics, ComputingMilieux_MISCELLANEOUS, Excitation
Abstract

Gamma-rays emitted from hot nuclei of mass around 115 and excitation energies above 300 MeV, formed in the 36 Ar + 90 Zr at 27 MeV/u, 36 Ar + 94 Zr at 32 MeV/u and 36 Ar + 98 Mo at 37 MeV/u, have been measured with the MEDEA multidetector in coincidence with evaporation residues. The γ-ray yield from the decay of the Giant Dipole Resonance is independent of excitation energy and of bombarding energy.

Published
1995
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8. Signature of a two-phonon state through its proton decay pattern

Author

M. Lamehi-Rachti, T. Suomijärvi, P. Massolo, Ph. Chomaz, A. Gillibert, A. van der Woude, J.C. Roynette, Didier Beaumel, Y. Blumenfeld, J. A. Scarpaci, I. Lhenry, J.P. Garron, N. Frascaria, N. Alamanos, 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), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Decay scheme, Proton, 010308 nuclear & particles physics, Proton decay, Isoscalar, Nuclear Theory, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Inelastic scattering, 01 natural sciences, 24.30.Cz, 25.70.Bc, 25.70.Ef, Giant resonance, Excited state, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon
Abstract

Inelastic scattering of 50 MeV/nucleon [sup 40]Ca on [sup 40]Ca was measured in coincidence with protons in order to investigate the excitation and decay of highly excited states in [sup 40]Ca. The proton decay pattern corresponding to an excitation region around 34 MeV shows the characteristic behavior expected of the direct decay of a two-phonon state. Thus, by using this novel method, the presence of a double-phonon state built with isoscalar giant resonances in [sup 40]Ca is demonstrated.

Published
1993
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9. Response of MEDEA BaF2 detectors to 20–280 MeV photons

Author

Paolo Piattelli, Paolo Finocchiaro, T. Suomijärvi, G. Bellia, J.C. Roynette, P.R. Silveira Gomes, Piera Sapienza, R. Coniglione, D. Pierroutsakou, I. Lhenry, N. Alamanos, J. L. Sida, E. Migneco, C. Maiolino, N. Frascaria, F. Auger, R. Alba, A. Gillibert, and A. Del Zoppo

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Range (particle radiation), Photon, Positron, Annihilation, Detector, Monte Carlo method, Physics::Accelerator Physics, Monochromatic color, Instrumentation, Energy (signal processing)
Abstract

The response function of MEDEA BaF2 crystals to high energy photons, up to 280 MeV, has been studied using monochromatic γ-rays from the in flight annihilation of positron beams. The experimental response functions are compared to the results of Monte Carlo simulations based on the EGS3 code and parametrized over the whole investigated energy range.

Published
1993
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10. EDEN: a neutron time-of-flight multidetector for decay studies of giant states

Author

J. Guillot, J.C. Roynette, H. Lefort, H. Laurent, P. Volkov, S. Fortier, D. Beaumel, Y. Blumenfeld, Sijtze Brandenburg, S. Gales, KVI - Center for Advanced Radiation Technology, Damage and Repair in Cancer Development and Cancer Treatment (DARE), Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, NUCLEI, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Resolution (electron density), Scintillator, 7. Clean energy, 01 natural sciences, Nuclear physics, Time of flight, 0103 physical sciences, Neutron, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], DETECTION EFFICIENCY, Nuclear Experiment, 010306 general physics, RESONANCES, Instrumentation, Overall efficiency
Abstract

A neutron time-of-flight multidetector has been built to study the decay of giant states. It is made of 40 individual detectors. A liquid scintillator is used for neutron-gamma-ray pulse shape discrimination. The overall efficiency of the multidetector (epsilonOMEGA/4pi) is 1% for 6 MeV neutrons and the energy resolution is about 60 keV and 500 keV for 1 MeV and 6 MeV neutrons respectively.

Published
1993
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11. Publisher’s Note: Probing preformedαparticles in the ground state of nuclei [Phys. Rev. C82, 031301 (2010)]

Author

E. Khan, P. Desesquelles, E. C. Pollacco, A. Chbihi, T. Zerguerras, H. Idbarkach, Didier Beaumel, J. A. Scarpaci, J.C. Roynette, Philippe Chomaz, E. Plagnol, Denis Lacroix, A. Shrivastava, J.D. Frankland, N. Frascaria, Y. Blumenfeld, C. Bhar, Muriel Fallot, J.L. Laville, M. Assié, L. Lefebvre, and P. Roussel-Chomaz

Subjects
Nuclear physics, Physics, Isotopes of calcium, Nuclear and High Energy Physics, Light nucleus, Isotope, Stable isotope ratio, Alpha particle, Atomic physics, Ground state, α particles, Charged particle
Published
2010
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12. Probing preformedαparticles in the ground state of nuclei

Author

P. Desesquelles, J.A. Scarpaci, M. Fallot, J. L. Laville, N. Frascaria, T. Zerguerras, J. Frankland, C. Bhar, E. Plagnol, P. Roussel-Chomaz, L. Lefebvre, A. Shrivastava, J.C. Roynette, H. Idbarkach, M. Assié, D. Beaumel, A. Chbihi, E. C. Pollacco, Ph. Chomaz, D. Lacroix, Elias Khan, and Y. Blumenfeld

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Nuclear Theory, Elementary particle, Alpha particle, 01 natural sciences, Charged particle, Baryon, 0103 physical sciences, Continuum (set theory), Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon, Ground state
Abstract

In this Rapid Communication, we report on $\ensuremath{\alpha}$-particle emission through the nuclear breakup in the reaction $^{40}\mathrm{Ca}$ on a $^{40}\mathrm{Ca}$ target at 50 A MeV. It is observed that, similar to nucleons, $\ensuremath{\alpha}$ particles can be emitted to the continuum with very specific angular distribution during the reaction. The $\ensuremath{\alpha}$-particle properties seem to be compatible with an $\ensuremath{\alpha}$ cluster in the daughter nucleus that is perturbed and is emitted by the short-range nuclear attraction of the collision partner. A time-dependent theory that describes the $\ensuremath{\alpha}$-particle wave-function evolution is able to qualitatively reproduce the observed angular distribution. This mechanism offers new possibilities for studying $\ensuremath{\alpha}$-particle properties in the nuclear medium.

Published
2010
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13. Decay of the giant quadrupole resonance and higher excitation states in 40CA1

Author

I. Lhenry, B. Fernandez, A. van der Woude, J.C. Roynette, J. A. Scarpaci, Y. Blumenfeld, N. Alamanos, N. Frascaria, J.P. Garron, A. Lépine, T. Suomijärvi, A. Gillibert, and Ph. Chomaz

Subjects
World Wide Web, Nuclear physics, Physics, Nuclear and High Energy Physics, Identification (information), business.industry, Mediation, The Internet, Webometrics, Web mapping, business
Abstract

The Web and its tools of orientation: how better to understand the information available on the Internet by the analysis of references? In the incessant and chaotic frenzy of the Internet, suitable tools and techniques are urgently required for use by information professionals. The Internet has become a leading venue for communication among researchers, both scientists and other scholars. The role of mediation for these professionals has never been so important, owing to the actual deficiencies of the search systems on the Internet. This article expounds the tools that are now available for the identification and evaluation of Internet sources. After a discussion of the techniques of discrimination and cartography, a method of constructing a navigation map of the Web by the analysis of citations is explained.

Published
1992
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14. Projectile like fragment production in14N-induced reactions at projectile energies of 60 MeV A

Author

J.P. Garron, J.C. Roynette, J.C. Jacmart, R. Glasow, W. von Oertzen, W. Weller, R. Santo, D. Grzonka, N. Frascaria, H. G. Bohlen, and Y. Blumenfeld

Subjects
Physics, Momentum, Nuclear physics, Nuclear and High Energy Physics, Fragment (computer graphics), Projectile, Nuclear Theory, Atomic physics, Nuclear Experiment, Projectile fragmentation, Ion
Abstract

Projectile fragmentation of 60 MeV A 14N ions has been studied by measuring isotopically separated fragments from A=3-13. The data are analysed within the Goldhaber model. The extracted reduced momentum widths sigma 0 are found to be nearly constant and close to values at relativistic energies.

Published
1990
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15. Excitation of giant resonances in heavy-ion reactions at intermediate energies: Results from the 40Ar + 90Zr and 208Pb experiments at 41 MeVu

Author

N. Frascaria, J.C. Roynette, Didier Beaumel, W. Mittig, J. Gastebois, Ph. Chomaz, J. A. Scarpaci, T. Suomijärvi, B. Fernandez, Y. Blumenfeld, J.P. Garron, J. Barrette, 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), 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 de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Projectile, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Inelastic scattering, 01 natural sciences, Ion, 0103 physical sciences, Coulomb, Heavy ion, Atomic physics, 010306 general physics, Multipole expansion, Excitation
Abstract

Giant resonances in 90 Zr and 208 Pb have been studied by inelastic scattering of 40 Ar at 41 MeV/u. Strength distributions and exhausted sum-rule values of different multipolarities are presented. The peak-to-background ratios and differential cross sections from inelastic scattering of heavy ions are compared to those obtained with light projectiles. The influence of Coulomb interaction on the excitation of giant resonances and the possibility to study high multipole resonances by intermediate-energy heavy ions are discussed.

Published
1990
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16. Decay of 1, 2 and 3-phonon states in $^{40}$Ca

Author

A. Chbihi, J.D. Frankland, J.L. Laville, Philippe Chomaz, J. A. Scarpaci, M. Fallot, T. Zerguerras, N. Frascaria, E. C. Pollacco, Y. Blumenfeld, J.C. Roynette, P. Desesquelles, P. Roussel-Chomaz, A. Shrivastava, E. Plagnol, Elias Khan, 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), 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), Peter von Neumann-Cosel, Thomas Aumann, INDRA, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Decay scheme, Missing energy, Spectrometer, 010308 nuclear & particles physics, Phonon, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, Particle decay, Giant resonance, 0103 physical sciences, High Energy Physics::Experiment, Atomic physics, 010306 general physics, Nuclear Experiment, Excitation
Abstract

International audience; Inelastic scattering of 40Ca on 40Ca at 50 A.MeV has been measured in coincidence with protons at the GANIL facility using a very performant set-up. The SPEG spectrometer was associated with 240 CsI(Tl) scintillators of the INDRA 4π array, allowing for the measurement of complete decay events. The missing energy method was applied to these events to study the particle decay of collective states. For events with excitation energy between 42 and 55 MeV, a direct decay branch by three protons towards the low energy states of 37Cl gives the first evidence for a 3-phonon giant resonance state. A significant direct decay branch by alpha-particles of the GQR is also measured for the first time.

Published
2006
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17. Evidence for a three-phonon giant resonance state in 40Ca nuclei

Author

J. A. Scarpaci, P. Désesquelles, E. Khan, J.D. Frankland, Philippe Chomaz, E. Plagnol, E. C. Pollacco, Y. Blumenfeld, M. Fallot, J.L. Laville, P. Roussel-Chomaz, A. Chbihi, A. Shrivastava, N. Frascaria, J.C. Roynette, T. Zerguerras, 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), 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), INDRA, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Missing energy, 010308 nuclear & particles physics, Phonon, General Physics and Astronomy, Scintillator, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 24.30.Cz, 25.70.Bc, 25.70.Ef, 27.40.+z, Nuclear physics, Giant resonance, 0103 physical sciences, Atomic physics, 010306 general physics, Nuclear Experiment, Energy (signal processing), Radioactive decay, Excitation
Abstract

Expérience GANIL PTH NESTER; Inelastic scattering of $^{40}$Ca on $^{40}$Ca at 50 MeV/A has been measured in coincidence with protons at the GANIL facility. The SPEG spectrometer was associated with 240 CsI(Tl) scintillators of the INDRA 4$\pi$ array, allowing for the measurement of complete decay events. The missing energy method was applied to these events. For events with excitation energy between 42 and 55 MeV, a direct decay branch by three protons towards the low energy states of $^{37}$Cl gives the first evidence for a 3-phonon state built with giant resonances.

Published
2006
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18. Direct decay of the GQR in $^{40}$Ca through alpha-particle emission

Author

Philippe Chomaz, J. A. Scarpaci, A. Chbihi, P. Desesquelles, Y. Blumenfeld, Muriel Fallot, N. Frascaria, T. Zerguerras, A. Shrivastava, J.D. Frankland, E. C. Pollacco, J.C. Roynette, P. Roussel-Chomaz, E. Plagnol, J.L. Laville, Elias Khan, 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 SUBATECH Nantes (SUBATECH), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Nantes (UN)-Mines Nantes (Mines Nantes), 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), Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Bhabha Atomic Research Centre (BARC), Government of India, Department of Atomic Energy, 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), Mines Nantes (Mines Nantes)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Inelastic scattering, Missing energy, Spectrometer, 010308 nuclear & particles physics, 24.30.Cz, 23.60.+e, 24.50.+g, Alpha particle, Giant resonances, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Charged particle, Nuclear physics, Particle decay, 0103 physical sciences, High Energy Physics::Experiment, Alpha decay, Direct decay, Atomic physics, 010306 general physics, Nucleon, Nuclear Experiment
Abstract

NESTER PTH; Inelastic scattering of 40Ca on 40Ca at 50 MeV/A has been measured at the GANIL facility in coincidence with light charged particles. For the first time, the SPEG spectrometer was associated with 240 CsI(Tl) scintillators of the INDRA 4π array. The missing energy method, successfully used in previous experiments to study the nucleon decay of collective states is applied to the study of alpha-particle decay of the GQR. A significant direct decay branch by alpha-particles of the GQR in 40Ca is measured for the first time.

Published
2005
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19. Reaction dynamics and hot nuclei formation in the36Ar+98Moreaction at37AMeVstudied through light charged particle andγ-ray emission

Author

N. Alamanos, Ph. Chomaz, K. Loukachine, Maria Colonna, C. Agodi, J.C. Roynette, P. Piattelli, G. Bellia, J. A. Scarpaci, F. Auger, Domenico Santonocito, Paolo Finocchiaro, T. Suomijärvi, R. Coniglione, R. Alba, A. Gillibert, J.H. Le Faou, C. Maiolino, E. Migneco, Paolo Sapienza, N. Frascaria, A. Del Zoppo, and Y. Blumenfeld

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Reaction dynamics, 0103 physical sciences, Atomic physics, 010306 general physics, Particle beam, Charged particle beam, 01 natural sciences, Charged particle
Published
2002
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20. Disappearence of collective motion in very hot nuclei

Author

A. Gillibert, Paolo Piattelli, J.A. Scarpaci, Domenico Santonocito, Paolo Sapienza, Ph. Chomaz, J.H. Le Faou, R. Coniglione, Paolo Finocchiaro, R. Alba, C. Maiolino, C. Agodi, E. Migneco, G. Bellia, Y. Blumenfeld, K. Loukachine, Maria Colonna, J.C. Roynette, N. Alamanos, F. Auger, T. Suomijärvi, N. Frascaria, A. Del Zoppo, 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), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Nuclear Theory, Collective motion, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Interpretation (model theory), Nuclear physics, 0103 physical sciences, Incident energy, Atomic physics, Nuclear Experiment, 010306 general physics, Excitation
Abstract

Gamma-rays emitted from hot nuclei with mass around 115 and excitation energies above 300 MeV, formed in the 36 Ar + 98 Mo reaction at 37 A MeV, have been measured. A comparison with previous experiments at lower bombarding energies shows a decrease of the γ-yield with increasing incident energy. A tentative interpretation based on dynamical calculations is proposed.

Published
1998

21. Fast Particle Emission in Inelastic Channels of Heavy-Ion Collisions

Author

N. Frascaria, T. Suomijärvi, Y. Blumenfeld, Denis Lacroix, H. Laurent, I. Lhenry, J.R. Jongman, P. Roussel-Chomaz, Didier Beaumel, V. Pascalon-Rozier, A. van der Woude, J.C. Roynette, J. A. Scarpaci, and Ph. Chomaz

Subjects
Nuclear physics, Physics, Projectile, Nuclear Theory, Heavy ion, Inelastic scattering, Proton emission, Nuclear Experiment, Nucleon, Excitation, Communication channel, Ion
Abstract

Inelastic scattering of heavy ions has been extensively used to study the nuclear excitations. In particular the decay of giant resonances has been investigated to infer information on their microscopic structure1. In addition to the target excitation several processes are known to contribute to the inclusive inelastic spectrum. The quasi-elastic knock-out process is a major contribution in the inelastic scattering of protons and α-particle projectiles. For heavier ions this contribution is expected to be smaller but still persists. Proton emission coming from the knock-out process was clearly observed and was detected in the direction of the recoiling target nucleus. Another process contributing to the inclusive inelastic spectrum is the pick-up break-up process2. In this process the projectile picks up a nucleon from the target, leaving it in a 1-hole configuration. The ejectile will then break-up again and feed the inelastic channel. This process gives rise to a plateau spreading over a large energy interval centered slightly above the bombarding energy per nucleon, with a width determined by the specific decay characteristics of the system.

Published
1998
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22. Hard photon and energetic proton emission in heavy ion collisions at intermediate energy

Author

Y. Blumenfeld, N. Frascaria, J.P. Garron, A. Del Zoppo, G. Bellia, N. Alamanos, K. Loukachine, J.H. Le Faou, A. Gillibert, Paolo Sapienza, T. Suomijärvi, F. Auger, J.C. Roynette, Paolo Piattelli, Paolo Finocchiaro, R. Coniglione, C. Agodi, R. Alba, Ph. Chomaz, Domenico Santonocito, J.A. Scarpaci, A. Péghaire, C. Maiolino, E. Migneco, 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), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Photon, 010308 nuclear & particles physics, Nuclear Theory, Detector, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Nuclear physics, Intermediate energy, 0103 physical sciences, Physics::Accelerator Physics, Heavy ion, Proton emission, Atomic physics, Nuclear Experiment, 010306 general physics, Very Energetic, ComputingMilieux_MISCELLANEOUS
Abstract

The emission of hard photons and pre-equilibrium protons has been investigated in exclusive clusive experiments performed with MEDEA detector. The observation of the γ-proton anticorrelation indicate that the dominant production mechanism is the first chance neutron-proton collisions. Very energetic protons, with energy more than twice the kinematical limit for nucleon-nucleon collisions, have been observed in several reactions.

Published
1998
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23. One-nucleon transfer reactions to continuum states induced by heavy ion projectiles

Author

Sydney Gales, J.P. Garron, S. Fortier, J. A. Scarpaci, J.C. Roynette, I. Lhenry, Y. Blumenfeld, J. Barreto, G.H. Yoo, H. Laurent, G. M. Crawley, N. Frascaria, Didier Beaumel, A. Gillibert, Ph. Chomaz, T. Suomijärvi, Joseph E. Finck, 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), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université 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), 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 Blanchet, Marie-Christine

Subjects
Physics, Nuclear and High Energy Physics, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], 010308 nuclear & particles physics, Q value, Semiclassical physics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Spectral line, Giant resonance, 0103 physical sciences, Quasiparticle, Neutron, Atomic physics, 010306 general physics, Nucleon, Excitation
Abstract

High-lying excitations were studied by means of the {sup 207}Pb{r_arrow}{sup 208}Pb, {sup 209}Bi{r_arrow}{sup 210}Bi, and {sup 59}Co{r_arrow}{sup 60}Ni stripping reactions and {sup 209}Bi{r_arrow}{sup 208}Pb and {sup 63}Cu{r_arrow}{sup 62}Ni pickup reactions induced by {sup 20}Ne and {sup 36}Ar projectiles at 48 and 42 MeV/nucleon, respectively. In the stripping spectra, structures a few MeV wide are observed at excitation energies of 10{endash}15 MeV, embedded in a large continuum. The corresponding {ital Q} values suggest that these structures are predominantly due to single-particle excitations rather than to the excitation of collective states such as giant resonances. This interpretation is in agreement with a microscopic calculation showing that in the one-nucleon transfer reactions only a small part of the cross section is due to the collective excitations. The overall shape of the neutron stripping spectra is well reproduced by the semiclassical reaction model of Bonaccorso and Brink, which treats on the same footing both the breakup of the projectile and the transfer to single-particle resonances. {copyright} {ital 1996 The American Physical Society.}

Published
1996

24. The giant dipole resonance in hot Sn nuclei

Author

J.C. Roynette, A. Gillibert, T. Suomijärvi, D. Pierroutsakou, F. Auger, N. Frascaria, J. L. Sida, N. Alamanos, I. Lhenry, P. R. S. Gomes, Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, Angular momentum, 010308 nuclear & particles physics, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Resonance (particle physics), Spectral line, Dipole, Excited state, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Saturation (chemistry), Excitation, Nuclear Physics
Abstract

We have studied the Giant Dipole Resonance (GDR) built on the excited states of 112Sn formed in the fusion of 19F with 93Nb. The excitation energy of the compound nucleus 112Sn was 130 and 152 MeV. High-energy γ-rays were detected in a 7-element BaF2 cluster and 4 NaI(Tl) scintillators. Coincidences with the evaporation residues detected in two parallel-plate avalanchecounters ensured that the γ-rays were associated with fusion events. In order to study the characteristics of the GDR, we have performed analyses of the γ-ray spectra within the statistical model, using a continuous evolution of the GDR centroid energy with the mass and the temperature of the emitting nucleus, and a nuclear temperature dependent level density parameter. The theoretical prescriptions concerning the evolution of the GDR width with excitation energy have been tested. We show that, in order to reproduce the γ-spectra, the increase of the width must be more rapid than the two theoretical predictions. The width has to reach large values, of the order of 15 to 20 MeV above 100 MeV of excitation energy. These values are greater than the saturation value of about 12 MeV which has been published following the analyses using constant parameters. On this condition, the shape of the spectra can be reproduced with or without a saturation of the width. It is therefore not possible to say if the increase of the width is due to angular momentum effects or to collisional effects.

Published
1996

25. The Giant Dipole Resonance Built on Highly Excited States

Author

Paolo Finocchiaro, M. Lamehi-Rachti, C. Agodi, N. Alamanos, N. Frascaria, J.C. Roynette, J.H. Le Faou, A. Del Zoppo, R. Liguori-Neto, Paolo Sapienza, J.P. Garron, G. Bellia, F. Auger, P. Piattelli, J. J. Gaardhøje, Domenico Santonocito, T. Suomijärvi, R. Alba, R. Coniglione, Y. Blumenfeld, E. Migneco, C. Maiolino, Ph. Chomaz, A. Gillibert, and J.A. Scarpaci

Subjects
Physics, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Evaporation, Resonance, Charged particle, Dipole, Excited state, Yield (chemistry), Giant resonance, Physics::Accelerator Physics, Atomic physics, Nuclear Experiment, Excitation
Abstract

Gamma-rays emitted from hot nuclei of mass around 115 and excitation energies above 300 MeV, formed in the 36Ar + 90Zr at 27 MeV/u, 36Ar + 94Zr at 32 MeV/u and 36Ar + 98Mo at 37 MeV/u, have been measured with the MEDEA multidetector in coincidence with light charged particles and evaporation residues. The γ-ray yield from the decay of the Giant Dipole Resonance is independent of excitation energy and of bombarding energy.The best agreement with the data is obtained by assuming a cut-off the resonace γ-emission above an excitation energy of 250 MeV.

Published
1996
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26. Towards limiting temperatures in nuclei: the behavior of collective motion

Author

Philippe Chomaz, R. Alba, A. Gillibert, N. Alamanos, G.V. Russo, Paolo Piattelli, C. Maiolino, N. Frascaria, T. Suomijärvi, R. Coniglione, C. Agodi, G. Bellia, J. A. Scarpaci, R. Liguori-Neto, J.C. Roynette, F. Auger, Le Faou Jh, M. Lamehi-Rachti, Augusto Smerzi, J. J. Gaardhøje, E. Migneco, J.P. Garron, Y. Blumenfeld, Del Zoppo A, Domenico Santonocito, Paolo Sapienza, Paolo Finocchiaro, 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), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear reaction, Physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Gamma ray, General Physics and Astronomy, Resonance, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Electromagnetic radiation, Dipole, Giant resonance, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon, Excitation, 25.70.Ef, 24.30.Cz, 25.70.Gh
Abstract

Gamma rays emitted from hot nuclei with mass around 115 and excitation energies between 350 and 500 MeV, formed in the [sup 36]Ar + [sup 90]Zr reaction at 27 MeV/nucleon have been measured. The [gamma]-ray yield from the decay of the giant dipole resonance in these nuclei remains constant over the excitation energy range studied. This quenching of the [gamma] multiplicity cannot be explained by a continuous increase with temperature of the width of the resonance. Better agreement with the data is obtained by assuming a cutoff of [gamma] emission from the resonance above an excitation energy of 250 MeV. The existing data do not show entrance channel effects.

Published
1994
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27. Neutron decay of the excitation-energy region up to 60 MeV excited by heavy ion scattering. (I)$^{208}$Pb

Author

J.A. Bordewijk, T. Suomijärvi, Nils Olsson, N. Frascaria, A. Gillibert, Lars-Olof Nilsson, P. Roussel-Chomaz, A.M. van den Berg, J.A. Scarpaci, D. Chmielewska, Jan Blomgren, F. Auger, N. Alamanos, Y. Blumenfeld, A. van der Woude, J.C. Roynette, Sijtze Brandenburg, R. Turcotte, 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), and Damage and Repair in Cancer Development and Cancer Treatment (DARE)

Subjects
Nuclear reaction, Nuclear and High Energy Physics, GIANT MONOPOLE RESONANCE, Population, Coulomb excitation, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, INELASTIC-SCATTERING, Nuclear physics, SN-124, COULOMB-EXCITATION, 0103 physical sciences, PB-208(O-17, SPECTRA, Neutron, 010306 general physics, education, PHOTON DECAY, MEV/NUCLEON, Physics, education.field_of_study, Decay scheme, E = 1428 MEV, 010308 nuclear & particles physics, O-17')(208-X)PB, MEASURED NEUTRON DECAY SPECTRUM, PB-208 DEDUCED CONTINUUM NEUTRON DECAY FEATURES, PB-208(O-17, O-17')(208-X)PB, CONTINUUM, STATES, Excited state, ANGULAR CORRELATION OF HOLE-STATE POPULATION VERSUS PB-208 EXCITATION ENERGY, High Energy Physics::Experiment, DIPOLE RESONANCE, Atomic physics, Nucleon
Abstract

The neutron decay of the continuum in Pb-208, excited by small-angle inelastic scattering of 84 MeV/nucleon O-17 ions in the range from 1.5-degrees, to 4.5-degrees, has been measured. Statistical decay was found to dominate the excitation-energy interval studied, up to 60 MeV. In the excitation-energy interval of about 10 to 30 MeV a distinct direct-decay component to the hold states in Pb-207 and a decay pattern resembling pre-equilibrium decay was observed. The angular correlation of the hole-state population suggests that in addition to the direct decay to the hole states in Pb-207, there is another, unidentified process populating the same states.

Published
1994

28. Neutron decay of the excitation-energy region up to 60 MeV excited by heavy-ion scattering.(II) $^{90}$Zr and $^{124}$Sn

Author

A.M. van den Berg, N. Alamanos, T. Suomaijärvi, J.A. Scarpaci, Sijtze Brandenburg, Nils Olsson, R. Turcotte, A. van der Woude, J.C. Roynette, J.A. Bordewijk, Y. Blumenfeld, Jan Blomgren, A. Gillibert, D. Chmielewska, Lars-Olof Nilsson, P. Roussel-Chomaz, F. Auger, N. Frascaria, Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Decay scheme, 010308 nuclear & particles physics, Scattering, Nuclear Theory, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Ion, Nuclear physics, Excited state, 0103 physical sciences, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Excitation
Abstract

The neutron decay of the continuum in Zr-90 and Sn-124, excited by inelastic scattering of 84A MeV O-17 ions in the range from 1.5 to 4.5-degrees, has been measured. Statistical decay was found to dominate the excitation-energy interval studied, up to about 50 MeV. In the excitation-energy interval from the neutron threshold up to about 35 MeV a distinct direct-decay component to the hole states in Zr-89 and Sn-123 was observed. In addition, a decay pattern resembling pre-equilibrium decay was observed for Zr-90. In the excitation energy spectrum of Zr-90 gated by low-energy (

Published
1994

29. The giant dipole resonance built on highly excited states - results of the MEDEA experiment

Author

G. Bellia, R. Liguori-Neto, J.C. Roynette, C. Agodi, M. Lamehi-Rachti, Y. Blumenfeld, R. Alba, Domenico Santonocito, G.V. Russo, Augusto Smerzi, J.H. Le Faou, N. Alamanos, Paolo Piattelli, R. Coniglione, J. J. Gaardhøje, J.P. Garron, Paolo Finocchiaro, E. Migneco, T. Suomijärvi, Paolo Sapienza, C. Maiolino, Ph. Chomaz, J.A. Scarpaci, A. Gillibert, N. Frascaria, A. Del Zoppo, F. Auger, 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), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Barium fluoride, Resonance, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Charged particle, Spectral line, chemistry.chemical_compound, Dipole, chemistry, Excited state, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Excitation, ComputingMilieux_MISCELLANEOUS
Abstract

Gamma-rays, light charged particles and evaporation residues emitted from hot nuclei formed in the 36 Ar + 90 Zr reaction at 27 MeV/u have been measured with a nearly 4π barium fluoride multidetector. It is shown that hot Sn-like nuclei with a range of excitation energies between 300 and 600 MeV are produced. The γ-ray yield from the decay of the Giant Dipole Resonance in these nuclei is shown to remain constant over this excitation energy range. The measured γ-ray spectra are compared with statistical calculations encompassing several recent theoretical models for the quenching of gamma-ray emission from the dipole resonance at very high temperatures.

Published
1993
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30. Some recent results on neutron decay of $^{208}$Pb excited to energies in the 14 to 25 MeV range

Author

T. Suomijärvi, J. A. Scarpaci, N. Alamanos, Lars-Olof Nilsson, A. van der Woude, J.C. Roynette, F. Auger, Nils Olsson, J.A. Bordewijk, Sijtze Brandenburg, Y. Blumenfeld, N. Frascaria, A. Gillibert, D. Chmielewska, P. Roussel-Chomaz, A.M. van den Berg, R. Turcotte, Jan Blomgren, 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), and Damage and Repair in Cancer Development and Cancer Treatment (DARE)

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), 010308 nuclear & particles physics, GIANT MONOPOLE RESONANCE, Nuclear Theory, Resonance, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, DIPOLE, REGION, Nuclear physics, Dipole, Excited state, 0103 physical sciences, Neutron, High Energy Physics::Experiment, Atomic physics, 010306 general physics, Nuclear Experiment, Excitation
Abstract

First results of an 208 Pb( 17 0, 17 0'n) 207 Pb experiment at 84 MeV n , designed to study the neutron decay of the Giant Dipole Resonance and the region above, is presented. Direct decay up to an excitation energy of 25 MeV in 208 Pb has been observed. The direct decay branch in the GDR energy region is about 5%.

Published
1993

31. Excitation of giant resonances in $^{208}$Pb $^{120}$Sn $^{90}$Zr and $^{60}$Ni by 84 MeV/nucleon $^{17}$O ions

Author

A. Gillibert, J. Barrette, B. Fernandez, S. K. Mark, Y. Blumenfeld, A. van der Woude, P. Roussel-Chomaz, J.P. Garron, J. Gastebois, J. A. Scarpaci, J.C. Roynette, R. Liguori Neto, A. Miczaika, T. Suomijärvi, N. Frascaria, N. Alamanos, F. Auger, R. Turcotte, Roy A. Lacey, A.M. van den Berg, L. Rochais, D. Pierroutsakou, Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Isoscalar, Nuclear Theory, Resonance, Coulomb excitation, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, 0103 physical sciences, Quadrupole, Sum rule in quantum mechanics, Atomic physics, 010306 general physics, Excitation
Abstract

Elastic and inelastic scattering of 1435 MeV 17O ions on 208Pb, 120Sn, 90Zr and 60Ni have been measured. Hindrance in the excitation of the first 3− states is observed. Parameters of the isoscalar giant monopole and quadrupole resonances are obtained. The quadrupole resonance exhausts ∼ 55% of the energy-weighted sum rule while the observed monopole resonance corresponds to more than 100% of the sum rule. Strength is also observed at high excitation energy in all targets.

Published
1993
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32. Study of the continuum in heavy ion inelastic spectra by light particle coincidence measurements

Author

A. van der Woude, J.P. Garron, J.C. Roynette, J. A. Scarpaci, Y. Blumenfeld, N. Alamanos, A. Lépine, B. Fernandez, N. Frascaria, T. Suomijärvi, A. Gillibert, Ph. Chomaz, Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Scattering, Continuum (design consultancy), Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Spectral line, Coincidence, Charged particle, ENERGY, Cross section (physics), EXCITATION, 0103 physical sciences, GIANT-RESONANCES, SCATTERING, PB-208, Atomic physics, Nuclear Experiment, 010306 general physics, Excitation, MEV/NUCLEON
Abstract

The continuum in heavy ion inelastic spectra contains, in addition to the excitation of target nucleus states, contributions from pick-up break-up and knock out reactions. In the case of the 40 Ca + 40 Ca collision at 50 MeV/N these contributions are separated and their relative importance assessed by the measurement of light charged particles in coincidence with the inelastically scattered fragments. The pick-up break-up contribution is found to make up less than half of the cross section at high excitation energies, conversely, the knock out process is important.

Published
1991
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33. Transfer and fragmentation reactions of $^{14}$N at 60 MeV/u

Author

W. Lahmer, W. von Oertzen, R. Glasow, J.C. Roynette, N. Frascaria, J.P. Garron, W. Weller, R. Santo, J.C. Jacmart, D. Grzonka, H. G. Bohlen, Y. Blumenfeld, A. Miczaika, Institut de Physique Nucléaire d'Orsay (IPNO), and 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)

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Projectile, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Spectral line, Nuclear physics, Fragmentation (mass spectrometry), Isotopes of carbon, 0103 physical sciences, Dissipative system, Incident energy, Nuclear fusion, Atomic physics, 010306 general physics
Abstract

Inclusive energy spectra and cross sections of reaction products close to the14N projectile (11C,12C,13C,15N and15O) have been measured in the angular rangeθL =1.2°–4.2° at an incident energy of 60 MeV/u for five different target nuclei (12C,27Al,58Ni,90Zr and208Pb). Two components are found to be systematically present in the energy spectra of the carbon isotopes, the first similar to that observed at relativistic energies and the second shifted down in energy characteristic for a very dissipative process. The dependence of the differential and integrated cross sections on the target mass indicates that the two-body final channels (14N,13C), (14N,15N) and (14N,15O) are strongly correlated to the fragmentation channels.

Published
1990

34. Experimental study of theNe20+C12system

Author

J.M. Loiseaux, J.C. Roynette, Ph. A. Martin, P. deSaintignon, H. Doubre, and E. Plagnol

Subjects
Nuclear reaction, Elastic scattering, Physics, Nuclear and High Energy Physics, Scattering, Excited state, Born approximation, Inelastic scattering, Atomic physics, Excitation, Oxygen-16
Abstract

Excitation functions for elastic, inelastic, and four-particle transfer channels of the /sup 12/C + /sup 20/Ne system were measured from 17 to 35 MeV (c.m.). The elastic scattering data (excitation functions and angular distribution at 24.7 MeV) have been analyzed with the optical model. Elastic and inelastic scattering are also studied in the framework of the coupled-channel Born approximation. The results emphasize the importance of the 2/sup +/ state of /sup 20/Ne in the descciption of the absorption. The comparison with the /sup 16/O + /sup 16/O system is discussed.

Published
1978
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35. Investigation of the nuclear continuum byCa40inelastic scattering onCa40at 160 MeV

Author

N. Frascaria, J.P. Garron, J.C. Jacmart, J.C. Roynette, M. Lattuada, D. Ardouin, and Y. Blumenfeld

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Angular range, Angular distribution, Scattering, Giant resonance, Incident energy, Atomic physics, Inelastic scattering, Nuclear Experiment, Excitation
Abstract

The $^{40}\mathrm{Ca}$ + $^{40}\mathrm{Ca}$ reaction has been studied at 160 MeV incident energy. Low lying peaks are observed in the inelastic channel together with a broad bump at 26 MeV total excitation energy. A comparison is made with results obtained in the same reaction at higher bombarding energy.NUCLEAR REACTIONS $^{40}\mathrm{Ca}+^{40}\mathrm{Ca}\ensuremath{-}{E}_{\mathrm{inc}}=160$ MeV; measured $\ensuremath{\sigma}(\ensuremath{\theta},E)$; angular range 6\ifmmode^\circ\else\textdegree\fi{} to 40\ifmmode^\circ\else\textdegree\fi{}; compared to higher energy results.

Published
1982
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36. Elastic scattering ofCa40byCa40

Author

J.C. Roynette, H. Doubre, N. Poffé, M. Riou, E. Plagnol, and J.C. Jacmart

Subjects
Elastic scattering, Nuclear reaction, Physics, Nuclear and High Energy Physics, Range (particle radiation), Distribution (mathematics), Scattering, Atomic physics, Absorption (electromagnetic radiation), Excitation, S-matrix
Abstract

Angular distributions for the elastic scattering of /sup 40/Ca by /sup 40/Ca at E/sub c. m./ = 64.8, 71.8, 88, 93, 112.5, and 120 MeV and excitation functions at 60/sup 0/, 70/sup 0/, and 90/sup 0/ (c.m.) over the c.m. energy range 55--120 MeV have been measured. Strong-absorption-model and optical-model analyses are presented. The predictions of several theoretical interaction potentials are compared with the data. The absence of structure in the excitation functions is studied and explained by the large mass and charge of the colliding nuclei.

Published
1977
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37. HIGH EXCITATION ENERGY STRUCTURES IN HEAVY ION COLLISIONS ON A208Pb TARGET

Author

J.C. Jacmart, A. Gamp, M. Buenerd, J.C. Roynette, Ph. Chomaz, D. Lebrun, W. von Oertzen, Y. Blumenfeld, J.P. Garron, N. Frascaria, W. Bohne, Ph Martin, 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), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)

Subjects
Spectrometer, Chemistry, Nuclear Theory, General Engineering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Spectral line, Time of flight, medicine.anatomical_structure, [PHYS.HIST]Physics [physics]/Physics archives, medicine, Physics::Accelerator Physics, Heavy ion, Atomic physics, Nuclear Experiment, Nucleus, Energy (signal processing), Excitation
Abstract

Energy spectra of fragments from the 36Ar +208Pb reaction at 11 MeV/n and 20Ne + 208Pb reaction at 30 MeV/n were measured using a time of flight spectrometer. Structures ranging up to 130 MeV excitation energy are observed in the inelastic spectra. These structures are shown to be due to an excitation of the208Pb target nucleus.

Published
1984
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38. Correlations between emerging alpha-particles and heavy ions in 32S+197 Au collisions

Author

N. Poffé, A. Gamp, H. Doubre, J.C. Jacmart, J. Wilczynski, J.C. Roynette, Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Field (physics), 010308 nuclear & particles physics, Projectile, Nuclear Theory, Alpha particle, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Ion, Nuclear physics, medicine.anatomical_structure, Coincident, 0103 physical sciences, Coulomb, medicine, Incident energy, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleus
Abstract

In-plane angular correlations between α-particles and projectile residue nuclei ( Z =5−22) emerging from 32 S+ 197 Au collisions have been measured at 373 MeV incident energy. In the combined Coulomb field of the projectile residue and the target nucleus coincident α-particles are strongly focused into a narrow cone. Model calculations indicate that α-emission originates from the region of the projectile which is facing the target nucleus during the collision.

Published
1978
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41. Deep inelastic fragment production in the 40Ca on 40Ca interaction at 278 MeV

Author

J.C. Roynette, N. Poffé, N. Frascaria, P. Colombani, C. Stephan, J.C. Jacmart, H. Doubre, and M. Riou

Subjects
Physics, Nuclear and High Energy Physics, Angular distribution, Fragment (logic), Coulomb barrier, Atomic physics, Nuclear Experiment, Kinetic energy, Specific kinetic energy
Abstract

Deep inelastic fragment production in the symmetrical reaction 40 Ca on 40 Ca has been studied at E lab = 278 MeV, high above the Coulomb barrier. Kinetic energy distributions and angular distributions have been obtained for products in the Z = 8−22 region. The two-body nature of the mechanism is discussed. Sequential decay of primary fragments is shown to be important.

Published
1975
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42. Isotope distribution of transfer products in the 40Ar + 232Th interaction at 295 MeV

Author

N. Poffé, J.C. Jacmart, P. Colombani, H. Doubre, J.C. Roynette, A. Weidinger, M. Riou, C. Stephan, and N. Frascaria

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Reaction mechanism, Isotope, Yield (chemistry), Atomic physics, Nuclear Experiment, Magnetic analysis, Ground state, Kinetic energy, Isotope distribution
Abstract

The light product nuclei from the reaction 40 Ar + 232 Th at 295 MeV and at laboratory angles of 18° and 40°, were identified using combined ΔE  E and magnetic analysis techniques. The yield distributions and the kinetic energies of the reaction products have very distinct properties at these two angles. The data are consistent with the assumption of a predominant “quasi-elastic” reaction mechanism at 40° and a “deep inelastic” one at 18°. The isotopic dependence of the cross sections is not correlated with the ground state Q -values of the reaction. The experimental kinetic energies at 18° favour the interpretation that the observed nuclei are close to primary reaction products.

Published
1975
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43. Excitation of giant resonances in 20Ne + 90Zr and 208Pb inelastic scattering at 40 MeV/u

Author

B. Fernandez, N. Frascaria, B. Berthier, J. Gastebois, J.C. Jacmart, W. Mittig, T. Suomijärvi, I. Linck, L. Kraus, J.C. Roynette, J. Barrette, P. Roussel-Chomaz, J.P. Garron, Didier Beaumel, Ph. Chomaz, Y. Blumenfeld, 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), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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 Recherches Subatomiques (DRS-IPHC), 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)-Université de Strasbourg (UNISTRA)-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), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches Subatomiques (IReS), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Coulomb excitation, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Inelastic scattering, 01 natural sciences, Spectral line, Cross section (physics), Giant resonance, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon, Excitation
Abstract

Spectromètre SPEG; The giant resonance region in the inelastic spectra from the reactions 20Ne + 90Zr and 20Ne + 208Pb at 40 MeV/nucleon has been studied with good energy and angular resolutions. The strength distributions of the different multipolarities contributing to the cross section were obtained without making any hypothesis on the excitation energies and shapes of the resonances. In the case of 208Pb the GDR strength was found to be strongly shifted towards lower excitation energies which can be explained by the exponentially decreasing Coulomb excitation probability. Furthermore, indications for a high multipolarity component in the resonance structure were found in both reactions.

Published
1989
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44. Contribution of decay products of transfer reactions to heavy-ion inelastic and transfer spectra

Author

Y. Blumenfeld, J.C. Roynette, J.C. Jacmart, J.P. Garron, Ph. Chomaz, N. Frascaria, Robert, Suzanne, Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], 010308 nuclear & particles physics, Monte Carlo method, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Kinetic energy, 01 natural sciences, Spectral line, Cross section (physics), Excited state, 0103 physical sciences, Atomic physics, Decay product, 010306 general physics, Anisotropy
Abstract

A study of decay product contributions to inclusive ejectile kinetic energy spectra is presented. Analytical formulae for the positions and widths of these contributions are derived from kinematical considerations. A formal integral expression for the double-differential cross section d 2 σ/ d Ω d E is given in the case of one-particle emission from an excited state of the ejectile. The effects of anisotropic angular distributions are studied. The differential cross sections are then computed by a Monte Carlo method and compared to experimental spectra over a large range of measured systems. The transfer-evaporation mechanism is shown to contribute strongly to the background of the spectra but not to be responsible for the narrow structure observed in some reactions.

Published
1985
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45. Investigation of one-nucleon transfer reactions between complex nuclei at incident energies between 3 MeV/nucleon and 8 MeV/nucleon

Author

J.C. Roynette, F. Pougheon, W. von Oertzen, J.C. Jacmart, C. Stephan, Miaoyuan Liu, and M. Riou

Subjects
Elastic scattering, Nuclear physics, Physics, Nuclear reaction, Nuclear and High Energy Physics, Angular momentum, Recoil, Carbon-13, Phase (waves), Atomic physics, Nucleon, Ground state
Abstract

Angular distributions of the ground state transitions in the reactions 11 B( 14 N, 15 O) 10 Be, 11 B( 14 N, 13 C) 12 C, 12 C( 11 B, 12 C) 11 B and 13 C( 12 C, 13 C) 12 C have been measured with a magnetic spectrometer as an identification system. The first two reactions (angular momentum transfer l = 2) measured at 41, 77 and 113 MeV show a clear damping of the oscillatory structures in the angular distributions. This effect was qualitatively reproduced by DWBA calculations which take into account a recoil phase, thus showing that the damping of the structures is due to the recoil of the transferred particle on the system. The reaction 11 B( 12 C, 11 B) 12 C ( l = 2) at 87 MeV with Q = 0 is well reproduced by the calculations, whereas the 13 C( 12 C, 13 C) 12 C reaction as the only l = 0 transition is in complete disagreement with theoretical expectations.

Published
1971
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47. Two-nucleon stripping reactions induced by 16O in 54Fe and 58Ni at 80 MeV

Author

P. Colombani, P. Roussel, F. Pougheon, H. Doubre, and J.C. Roynette

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Incident energy, Atomic physics, Nucleon, Stripping (fiber)
Abstract

Both the ( 16 O, 14 N) and ( 16 O, 14 C) reactions have been investigated on 54 Fe and 58 Ni target nuclei at 80 MeV incident energy. Both reactions are selective. The kinematical conditions have been found to act in two ways: (i) the high-spin states are enhanced and (ii) the states involving nucleons in the f- or p-shells are favoured. Three groups of T = 1 analog states have been located in 56 Ni and 60 Zn from a comparison of the two transfer reactions on the same target, and configuration assignments are attempted.

Published
1972
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48. Réactions (p, 2p) À 156 MeV

Author

M. Riou, M. Arditi, J.C. Jacmart, J.C. Roynette, F. Mazloum, and C. Ruhla

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Scintillation, Spectrometer, Physics::Instrumentation and Detectors, Scattering, Nuclear Theory, Resolution (electron density), Spectral line, Nuclear physics, Physics::Accelerator Physics, Atomic physics, Nuclear Experiment
Abstract

Quasi-free proton-proton scattering at 6 Li, 7 Li and 9 Be has been studied at 156 MeV with an overall energy resolution of 2.1 MeV for 6 Li and 1.7 MeV for 7 Li and 9 Be. Two magnetic spectrometers, multi-channel scintillation detectors or spark chambers and an on-line computer were used. Summed energy spectra and angular correlations of the components of these spectra are given. The results suggests 1p + 2s configuration mixing for external protons in 6 Li and 7 Li. The (1s) −1 splitting is observed for both nuclei.

Published
1967
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49. Réactions de transfert de plusieurs nucléons entre ions lourds

Author

J.C. Roynette

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, education.field_of_study, Stripping (chemistry), Population, Ion, medicine.anatomical_structure, medicine, Atomic physics, Nuclear Experiment, Nucleon, education, Nucleus, Excitation
Abstract

Population of n -particles- n -hole states is studied in three, four and five nucleon stripping reactions by heavy ions, leading to the 16 O residual nucleus. High-energy excitation levels of 16 O are obtained up to 26 MeV. All of these reactions are very selective, especially alpha transfer reactions. Several 2p-2h and 4p-4h states are populated by three and five nucleons transfer reactions. Angular distributions measured at forward angles (≧ 1.5° lab ) exhibit a typically diffractional pattern suggesting that a direct interaction mechanism is predominant.

Published
1970
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