B. Tamain - Academia.edu (original) (raw)

Papers by B. Tamain

AIP Conference Proceedings, 2007

Bimodality is observed on the size of the heaviest released fragment for semi-peripheral heavy io... more Bimodality is observed on the size of the heaviest released fragment for semi-peripheral heavy ion induced reactions in the intermediate energy domain. From lattice-gas calculations, this signal can sign a phase transition even if the system has not reached a complete equilibrium. It is shown from the data that it is correlated with other possible phase transition signals. The two

AIP Conference Proceedings, 1992

Coïncidences between at least 3 fragments emitted at large angle have been used to study central ... more Coïncidences between at least 3 fragments emitted at large angle have been used to study central collisions in the Ar+Au reactions at 30 and 60 MeV/u incident energies. For both energies, the formation of equilibrated very hot nuclei is evidenced. Excitation energy as high as 1 GeV are reached in the reaction at 60 MeV/u.

Physics Letters B, 1993

Coincident light particles and fragments produced in Kr+Au reactions at 27, 44 and 60 MeV/u have ... more Coincident light particles and fragments produced in Kr+Au reactions at 27, 44 and 60 MeV/u have been measured with a large solid-angle set-up. Energy spectra of Z=1, 2 and 3 particles sequentially emitted by the slowed-down projectile-like nucleus evolve between an evaporation and a fragmentation pattern, suggesting a saturation in the thermalisation process.

Physics Letters B, 1994

Events with fragment multiplicities up to eight have been detected with a large detector array in... more Events with fragment multiplicities up to eight have been detected with a large detector array in Pb + Au reactions at 29 MeV/ u. All collisions show a binary character irrespective of a possible further disassembly of the two highly excited primary partners. For the most violent collisions, dissipative orbiting is observed as well as full energy damping corresponding to excitation energies as high as 6 MeV/u.

Nuclear Physics A, 1972

ABSTRACT

Nuclear Physics A, 2005

Bimodality has been observed on the asymmetry between the charges of the two heaviest products re... more Bimodality has been observed on the asymmetry between the charges of the two heaviest products resulting from the decay of the QP released in peripheral Xe+Sn and Au+Au collisions from 60 to 100 MeV/u. Bimodality is observed for intermediate impact parameters for which the quasi-projectile is clearly identified. The two event families correspond to different excitation energies as it is expected in a first order phase transition picture. It seems that the relevant parameter which governs the phenomenon is the dissipated energy per nucleon. It is also shown that it is possible to correlate the bimodality signal with the negative heat capacity and the Delta scaling. All together, this set of data is coherent with a liquid-gas phase transition of finite pieces of nuclear matter.

Nuclear Instruments and Methods, 1974

Advances in Nuclear Dynamics, 1996

Within the framework of flow and multifragmentation study, the 36 Ar+ 58 Ni experiment has been p... more Within the framework of flow and multifragmentation study, the 36 Ar+ 58 Ni experiment has been performed at seven incident energies from 32 to 95 A • MeV with the INDRA detector at GANIL. After a brief description of the experimental setup , the main trends as well as the evolution of fragment distributions will be presented. Some results about reaction mechanisms for particular classes of events will conclude this report.

Nuclear Physics A, 1990

Charged particles and fragments emitted in reactions between 40Ar at energies ranging from 25 to ... more Charged particles and fragments emitted in reactions between 40Ar at energies ranging from 25 to 85 MeV/u and an 27A1 target have been detected in a geometry close to 4~ in the center of mass with the 4~ array MUR + TONNEAU. A new global variable, the average parallel velocity, has been used to sort the events as a function of the impact parameter value. The multiplicity of particles emitted from the interaction region increases strongly when the impact parameter value decreases, and reaches 7 in head-on reactions. The flow of these particles is attributed to scattering at negative angles. When the energy increases, compression gradually opposes this negative scattering, until the flow fails to zero. This is obtained at a beam energy in the range 70-80 MeV/u for impact parameters below 2 fm and increases with the impact parameter.This study as a function of the impact parameter and the energy should allow information both on the nucleon-nucleon cross section in medium and the EOS of nuclear matter to be obtained. In central reactions, incomplete fusion nuclei are formed at all incident energies. Their excitation energy increases with the incident energy. Above 36 MeV/u no heavy residue is left, the multiplicity of final products increases as well as the emission probability of several heavy fragments.

... Then, we will discuss the nature of the resulting excitation energy, namely the role of compr... more ... Then, we will discuss the nature of the resulting excitation energy, namely the role of compression or dynan-Acal effects in the process. ... DN Delis, K. Hanold, JC Meng, GF Peaslee, QC Sui, CJ Wozniak, LG Moretto, B. Libby, AC Mignerey, G. Guarino, N. Santoruvo, 1. lori ; Phys. ...

Annales de Physique, 1986

The intermediate energy heavy ion induced reactions are extensively studied for several years. In... more The intermediate energy heavy ion induced reactions are extensively studied for several years. In this paper, we try to summarize the present knowledge. The peripheral reactions appear to be intermediate between the fragmentation and the deep inelastic regimes. Many ...

International Journal of Modern Physics E, 2008

Cross sections, kinetic energy and angular distributions of fragments with charge 6 ≤ Z ≤ 28 emit... more Cross sections, kinetic energy and angular distributions of fragments with charge 6 ≤ Z ≤ 28 emitted in 78,82 Kr +40 C at 5.5 MeV/A reactions were measured at the GANIL facility using the INDRA apparatus. This experiment aims to investigate the influence of the neutron enrichment on the decay mechanism of excited nuclei. Data are discussed in comparison with predictions of transition state and Hauser-Feshbach models.

Nuclear Physics A, 2005

Finite systems such as atomic nuclei present at phase transition specific features different from... more Finite systems such as atomic nuclei present at phase transition specific features different from those observed at the thermodynamic limit. Several characteristic signals were found in samples of events resulting from heavy ion collisions at and above the Fermi energy. The concomitant observation of different signatures of a liquid-gas phase transition in nuclei on a given sample strongly supports the occurrence of this transition.

AIP Conference Proceedings, 2007

Bimodality is observed on the size of the heaviest released fragment for semi-peripheral heavy io... more Bimodality is observed on the size of the heaviest released fragment for semi-peripheral heavy ion induced reactions in the intermediate energy domain. From lattice-gas calculations, this signal can sign a phase transition even if the system has not reached a complete equilibrium. It is shown from the data that it is correlated with other possible phase transition signals. The two

AIP Conference Proceedings, 1992

Coïncidences between at least 3 fragments emitted at large angle have been used to study central ... more Coïncidences between at least 3 fragments emitted at large angle have been used to study central collisions in the Ar+Au reactions at 30 and 60 MeV/u incident energies. For both energies, the formation of equilibrated very hot nuclei is evidenced. Excitation energy as high as 1 GeV are reached in the reaction at 60 MeV/u.

Physics Letters B, 1993

Coincident light particles and fragments produced in Kr+Au reactions at 27, 44 and 60 MeV/u have ... more Coincident light particles and fragments produced in Kr+Au reactions at 27, 44 and 60 MeV/u have been measured with a large solid-angle set-up. Energy spectra of Z=1, 2 and 3 particles sequentially emitted by the slowed-down projectile-like nucleus evolve between an evaporation and a fragmentation pattern, suggesting a saturation in the thermalisation process.

Physics Letters B, 1994

Events with fragment multiplicities up to eight have been detected with a large detector array in... more Events with fragment multiplicities up to eight have been detected with a large detector array in Pb + Au reactions at 29 MeV/ u. All collisions show a binary character irrespective of a possible further disassembly of the two highly excited primary partners. For the most violent collisions, dissipative orbiting is observed as well as full energy damping corresponding to excitation energies as high as 6 MeV/u.

Nuclear Physics A, 1972

ABSTRACT

Nuclear Physics A, 2005

Bimodality has been observed on the asymmetry between the charges of the two heaviest products re... more Bimodality has been observed on the asymmetry between the charges of the two heaviest products resulting from the decay of the QP released in peripheral Xe+Sn and Au+Au collisions from 60 to 100 MeV/u. Bimodality is observed for intermediate impact parameters for which the quasi-projectile is clearly identified. The two event families correspond to different excitation energies as it is expected in a first order phase transition picture. It seems that the relevant parameter which governs the phenomenon is the dissipated energy per nucleon. It is also shown that it is possible to correlate the bimodality signal with the negative heat capacity and the Delta scaling. All together, this set of data is coherent with a liquid-gas phase transition of finite pieces of nuclear matter.

Nuclear Instruments and Methods, 1974

Advances in Nuclear Dynamics, 1996

Within the framework of flow and multifragmentation study, the 36 Ar+ 58 Ni experiment has been p... more Within the framework of flow and multifragmentation study, the 36 Ar+ 58 Ni experiment has been performed at seven incident energies from 32 to 95 A • MeV with the INDRA detector at GANIL. After a brief description of the experimental setup , the main trends as well as the evolution of fragment distributions will be presented. Some results about reaction mechanisms for particular classes of events will conclude this report.

Nuclear Physics A, 1990

Charged particles and fragments emitted in reactions between 40Ar at energies ranging from 25 to ... more Charged particles and fragments emitted in reactions between 40Ar at energies ranging from 25 to 85 MeV/u and an 27A1 target have been detected in a geometry close to 4~ in the center of mass with the 4~ array MUR + TONNEAU. A new global variable, the average parallel velocity, has been used to sort the events as a function of the impact parameter value. The multiplicity of particles emitted from the interaction region increases strongly when the impact parameter value decreases, and reaches 7 in head-on reactions. The flow of these particles is attributed to scattering at negative angles. When the energy increases, compression gradually opposes this negative scattering, until the flow fails to zero. This is obtained at a beam energy in the range 70-80 MeV/u for impact parameters below 2 fm and increases with the impact parameter.This study as a function of the impact parameter and the energy should allow information both on the nucleon-nucleon cross section in medium and the EOS of nuclear matter to be obtained. In central reactions, incomplete fusion nuclei are formed at all incident energies. Their excitation energy increases with the incident energy. Above 36 MeV/u no heavy residue is left, the multiplicity of final products increases as well as the emission probability of several heavy fragments.

... Then, we will discuss the nature of the resulting excitation energy, namely the role of compr... more ... Then, we will discuss the nature of the resulting excitation energy, namely the role of compression or dynan-Acal effects in the process. ... DN Delis, K. Hanold, JC Meng, GF Peaslee, QC Sui, CJ Wozniak, LG Moretto, B. Libby, AC Mignerey, G. Guarino, N. Santoruvo, 1. lori ; Phys. ...

Annales de Physique, 1986

The intermediate energy heavy ion induced reactions are extensively studied for several years. In... more The intermediate energy heavy ion induced reactions are extensively studied for several years. In this paper, we try to summarize the present knowledge. The peripheral reactions appear to be intermediate between the fragmentation and the deep inelastic regimes. Many ...

International Journal of Modern Physics E, 2008

Cross sections, kinetic energy and angular distributions of fragments with charge 6 ≤ Z ≤ 28 emit... more Cross sections, kinetic energy and angular distributions of fragments with charge 6 ≤ Z ≤ 28 emitted in 78,82 Kr +40 C at 5.5 MeV/A reactions were measured at the GANIL facility using the INDRA apparatus. This experiment aims to investigate the influence of the neutron enrichment on the decay mechanism of excited nuclei. Data are discussed in comparison with predictions of transition state and Hauser-Feshbach models.

Nuclear Physics A, 2005

Finite systems such as atomic nuclei present at phase transition specific features different from... more Finite systems such as atomic nuclei present at phase transition specific features different from those observed at the thermodynamic limit. Several characteristic signals were found in samples of events resulting from heavy ion collisions at and above the Fermi energy. The concomitant observation of different signatures of a liquid-gas phase transition in nuclei on a given sample strongly supports the occurrence of this transition.