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Accueil > Recherche & Enseignement

M. Marian Pârlog


Chercheur Associé (CDI CNRS)


Groupe : Structure Nucléaire


parlog lpccaen.in2p3.fr


Tél : +33 2 31 45 29 61



PUBLICATIONS

[in2p3-01348951] New semi-automatic method for reaction product charge and mass identification in heavy-ion collisions at Fermi energies

3 février 2017

This article presents a new semi-automatic method for charge and mass identification of charged nuclear fragments using either ∆E − E correlations between measured energy losses in two successive detectors or correlations between charge signal amplitude and rise time in a single silicon detector, (...)

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[in2p3-01345974] Reaction and fusion cross sections for the near-symmetric system $^{129}$Xe+$^{nat}$Sn from $8$ to $35$ $AMeV$

20 octobre 2016

item[Background]Heavy-ion reactions from barrier up to Fermi energy. \item[Purpose]Reaction and fusion cross sections determination. Fusion reactions induced by $^129Xe$ projectiles on $^natSn$ targets for energies ranging from $8$ A.MeV to $35$ A.MeV were measured with the INDRA (...)

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[in2p3-01368398] A New Neutron Time-of-Flight Array for β-Decay Studies

19 septembre 2016

A new time-of-flight array for β-delayed neutron spectroscopy (En 5 MeV) is being developed with the aim of improved performance compared to existing arrays. We report on the status of this development, in particular the study of the n-γ discrimination quality with digital electronics, a (...)

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[in2p3-01341120] FAZIA applications

4 juillet 2016

The present status and the perspectives of the FAZIA project are presented. The main achievements in terms of identification thresholds and isotopic resolution are discussed, together with the adopted technical solutions. The detector is particularly well suited for the investigation of isospin (...)

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[in2p3-01100158] Signals of Bose Einstein condensation and Fermi quenching in the decay of hot nuclear systems

6 juin 2016

We report experimental signals of Bose-Einstein condensation in the decay of hot Ca projectilelike sources produced in mid-peripheral collisions at sub-Fermi energies. The experimental setup, constituted by the coupling of the INDRA 4$\pi$ detector array to the forward angle VAMOS magnetic (...)

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[in2p3-01306171] $\alpha$ clustering in Ti isotopes: $^{40,44,48}$Ca + $\alpha$ resonant scattering

22 avril 2016

Measurements were made of the 4He(40,44,48Ca,α) resonant scattering reactions at 180° and up to Ec.m. ~ 11.5MeV, using the Thick Target Inverse Kinematics technique. These measurements are discussed, with a focus on assessing their usefulness for investigating α-clustering in medium mass (...)

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[in2p3-01300455] Signals of Bose Einstein condensation and Fermi quenching in the decay of hot nuclear systems

11 avril 2016

We report on first experimental observations of nuclear fermionic and bosonic components displaying different behaviours in the decay of hot Ca projectile-like sources produced in mid-peripheral collisions at sub-Fermi energies. The experimental setup, constituted by the coupling of the INDRA (...)

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[in2p3-01265779] Front-end electronics for the FAZIA experiment

2 février 2016

FAZIA is a multidetector specifically designed to optimize A and Z reaction product identification in heavy-ion collision experiments. This multidetector is modular and based on three-layer telescopes made of two silicon detectors followed by a thick (10 cm) CsI(Tl) scintillator read-out by a (...)

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[in2p3-00867220] Coulomb chronometry to probe the decay mechanism of hot nuclei

15 décembre 2015

In 129 Xe+ nat Sn central collisions from 8 to 25 MeV/A, the three-fragment exit channel occurs with a significant cross section. We show that these fragments arise from two successive binary splittings of a heavy composite system. The sequence of fragment production is determined. Strong (...)

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[in2p3-01226430] Isospin transport and reaction mechanism in nuclear reactions in the range 20–40 MeV/n

12 novembre 2015

In recent years, many efforts have been devoted to the investigation of the isospin degree of freedom in nuclear reactions. Comparing systems involving partners with different N/Z, it has been possible to investigate the isospin transport process and its influence on the final products (...)

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[in2p3-00730971] Neutron and charged particle identification by means of various detectors

4 juillet 2015

Identification methods for photons, neutrons and heavy ions by using scintillator and semiconductor detectors are discussed by stressing the advantages of signal digitization.

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[in2p3-00762387] β-delayed neutron emission studies

4 juillet 2015

The study of β-delayed neutron emission plays a major role in different fields such as nuclear technology, nuclear astrophysics and nuclear structure. However the quality of the existing experimental data nowadays is not sufficient for the various technical and scientific applications and new (...)

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[in2p3-00587352] Description of current pulses induced by heavy ions in silicon detectors (II)

4 juillet 2015

Current pulses induced in a silicon detector by 10 different heavy ion species at known energies around 10 AMeV have been sampled in time at high frequency. Their individual average shapes are quite well reproduced by a fit procedure based on our recent charge carrier collection treatment which (...)

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[in2p3-01171365] From Light to Heavy Nuclear Systems, Production and Decay of Fragments Studied with Powerful Arrays

4 juillet 2015

Reactions between heavy-ions at various energy regimes produce many nuclear fragments which can be populated in highly excited states. The study of these fragments, detected at the end of their particle decay, is important to investigate nuclear forces and structure effects. In recent years (...)

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[in2p3-01120218] Low-temperature technique of thin silicon ion implanted epitaxial detectors

4 juillet 2015

A new technique of large-area thin ion implanted silicon detectors has been developed within the R&D performed by the FAZIA Collaboration. The essence of the technique is the application of a lowtemperature baking process instead of high-temperature annealing. This thermal treatment is (...)

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[in2p3-01168776] Isospin transport phenomena and odd-even staggering in $^{84}$Kr+$^{112,124}$Sn collisions at 35 AMeV

3 juillet 2015

Experimental results concerning isospin transport phenomena and odd-even staggering in Z and N distributions are presented. Data refer to 84Kr+112,124Sn collisions at 35AMeV and they were collected with a high resolution FAZIA telescope, able to isotopically resolve ions up to Z ∼ 20. Evidences (...)

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[in2p3-00985888] Recent results from INDRA

3 juillet 2015

Recent results of the INDRA collaboration are presented in this contribution. They concern the evolution of reaction dynamics from the first stage of the collision to the production of fragments. Different probes are used to evidence the stopping/transparency, collective flow and the symmetry (...)

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[in2p3-01168867] Extracting information from partially depleted Si detectors with digital sampling electronics

3 juillet 2015

A study of the identification properties and of the energy response of a Si-Si-CsI(Tl) ΔE-E telescope exploiting a partially depleted second Si stage has been performed. Five different bias voltages have been applied to the second stage of the telescope, one corresponding to full depletion, the (...)

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[hal-00347268] Isospin diffusion in semi-peripheral $^{58}Ni$+$^{197}Au$ collisions at intermediate energies (I): Experimental results

3 juillet 2015

Isospin diffusion in semi-peripheral collisions is probed as a function of the dissipated energy by studying two systems $^58Ni$+$^58Ni$ and $^58Ni$+$^197Au$, over the incident energy range 52-74\AM. A close examination of the multiplicities of light products in the forward part of phase space (...)

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[hal-00720759] The behaviour of constrained caloric curves as ultimate signature of a phase transition for hot nuclei

3 juillet 2015

Simulations based on experimental data obtained from multifragmenting quasifused nuclei produced in central 129Xe + natSn collisions have been used to deduce event by event freeze-out properties on the thermal excitation energy range 4-12 AMeV. From these properties and temperatures deduced (...)

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[in2p3-00987060] Isospin transport phenomena and odd-even staggering in Z and N distributions in 84Kr+112,124Sn collisions at 35AMeV

3 juillet 2015

Experimental results concerning isospin transport phenomena and odd-even staggering in Z and N distributions are presented. Data refer to 84Kr+112,124Sn collisions at 35AMeV and they were collected with a high resolution FAZIA telescope, able to isotopically resolve ions up to Z ∼ 20. Evidences (...)

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[hal-00345772] Bimodal behavior of the heaviest fragment distribution in projectile fragmentation

3 juillet 2015

The charge distribution of the heaviest fragment detected in the decay of quasi-projectiles produced in intermediate energy heavy-ion collisions has been observed to be bimodal. This feature is expected as a generic signal of phase transition in non-extensive systems. In this paper we present (...)

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[in2p3-00494230] Study of Nuclear Stopping in Central Collisions at Intermediate Energies

3 juillet 2015

Nuclear stopping has been investigated in central nuclear collisions at intermediate energies by analyzing kinematically complete events recorded with the help of the 4π multidetector INDRA for a large variety of symmetric systems. It is found that the mean isotropy ratio defined as the ratio of (...)

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[in2p3-00772111] A single-chip telescope for heavy-ion identification

3 juillet 2015

A ΔE-E telescope exploiting a single silicon chip for both ΔE measurement and scintillation light collection has been tested. It is a Si-CsI(Tl) telescope tailored for mass identification of light charged particles and intermediate mass fragments. A procedure based on two different shaping (...)

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[in2p3-00966956] The FAZIA project in Europe: R&D phase

3 juillet 2015

The goal of the FAZIA Collaboration is the design of a new-generation 4π detector array for heavy-ion collisions with radioactive beams. This article summarizes the main results of the R&D phase, devoted to the search for significant improvements of the techniques for charge and mass (...)

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[in2p3-00736381] New isospin effects in central heavy-ion collisions at Fermi energies

3 juillet 2015

Isospin e ffects on multifragmentation properties were studied thanks to nuclear collisions between di fferent isotopes of xenon beams and tin targets. It is shown that, in central collisions leading to multifragmentation, the mean number of fragments and their mean kinetic energy increase with (...)

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[in2p3-00855243] Effects of irradiation of energetic heavy ions on digital pulse shape analysis with silicon detectors

3 juillet 2015

Detected energy, charge rise-time and pulse shape identfication capabilities of nTD silicon detectors under prolonged irradiation by energetic heavy ions have been studied. Sizeable effects on the amplitude and the risetime of the charge signal have been found for detectors irradiated with (...)

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[in2p3-00459378] Multifragmentation and phase transition for hot nuclei: recent progress

3 juillet 2015

Recent important progress on the knowledge of multifragmentation and phase transition for hot nuclei, thanks to the high detection quality of the INDRA array, is reported. It concerns i) the radial collective energies involved in hot fragmenting nuclei/sources produced in central and (...)

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[in2p3-01066044] In-medium effects for nuclear matter in the Fermi energy domain

3 juillet 2015

We study nuclear stopping in central collisions for heavy-ion induced reactions in the Fermi energy domain, between $15$ and $100$ A\,\textrmMeV. Using the large dataset of exclusive measurements provided by the $4\pi$ array \emphINDRA, we determine the relative degree of stopping as a function (...)

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[in2p3-00954513] Isospin transport in 84Kr + 112;124 Sn collisions at Fermi energies with the FAZIA detector

3 juillet 2015

Isotopically resolved fragments up to Z 20 have been studied in a test experiment by the FAZIA Collaboration with a three-stage telescope. The reactions 84Kr+112Sn (n-poor) and 84Kr+124Sn (n-rich) at 35 MeV/nucleon were measured. The telescope was located near the grazing angle, so the detected (...)

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[in2p3-00860105] Isospin transport in 84Kr+112,124Sn reactions at Fermi energies

3 juillet 2015

Isospin transport phenomena in dissipative heavy ion collisions have been investigated at Fermi energies with a beam of 84Kr at 35AMeV. A comparison of the /Z of light and medium products forward-emitted in the centre of mass frame when the beam impinges on a n-poor 112Sn and a n-rich 124Sn (...)

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[in2p3-00660911] X-ray fluorescence from the element with atomic number Z = 120

3 juillet 2015

An atomic clock based on X-ray fluorescence yields has been used to estimate the mean characteristic time for fusion followed by fission in reactions 238U + 64Ni at 6.6 MeV/A. Inner shell vacancies are created during the collisions in the electronic structure of the possibly formed Z=120 (...)

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[in2p3-00625611] Asymmetric fission in 78Kr+40Ca reactions at 5.5 MeV/nucleon

3 juillet 2015

Decay modes of excited nuclei formed in the 78,82Kr+40Ca reactions at 5.5 AMeV are investigated by means of exclusive measurements using the INDRA detector at GANIL. Light‐charged particles in coincidence with fragments show that, in the mechanism of asymmetric fission, the light partner (with (...)

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[in2p3-00462459] Influence Of The Neutron Richness On Binary Decays

3 juillet 2015

The influence of the neutron richness on binary decays is investigated in 78,82Kr+ 40Ca reactions at 5.5 MeV/A incident energy. Kinetic energy distributions and angular distributions of fragments with atomic number 6 ≤ Z ≤ 28 were measured using the 4π-INDRA array. Global features are compatible (...)

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[hal-00335974] Fragment properties of fragmenting heavy nuclei produced in central and semi-peripheral collisions.

3 juillet 2015

Fragment properties of hot fragmenting sources of similar sizes produced in central and semi-peripheral collisions are compared in the excitation energy range 5-10 AMeV. For semi-peripheral collisions a method for selecting compact quasi-projectiles sources in velocity space similar to those of (...)

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[in2p3-00753651] Comparison of charged particle identification using pulse shape discrimination and ΔE−E methods between front and rear side injection in silicon detectors

3 juillet 2015

The response of silicon-silicon-CsI(Tl) telescopes, developed within the FAZIA collaboration, to fragments produced in nuclear reactions 84Kr+120-124Sn at 35 A MeV, has been used to study ion identification methods. Two techniques are considered for the identification of the nuclear products in (...)

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[in2p3-00451188] Description of current pulses induced by heavy ions in silicon detectors

3 juillet 2015

The polarization of the electron-hole pairs induced by 80 MeV View the MathML source ions in a silicon detector was considered and connected to the relative dielectric permittivity. The dissociation of pairs was supposed to take place with a constant probability in a time unit. The exact (...)

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[in2p3-00951103] Energy measurement and fragment identification using digital signals from partially depleted Si detectors

3 juillet 2015

A study of identification properties of a Si-Si DE-E telescope exploiting an underdepleted residual-energy detector has been performed. Five different bias voltages have been used, one corresponding to full depletion, the others associated with a depleted layer ranging from 90% to 60% of the (...)

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[in2p3-00868032] N and Z odd-even staggering in Kr + Sn collisions at Fermi energies

3 juillet 2015

The odd-even staggering of the yield of final reaction products has been studied as a function of proton (Z) and neutron (N) numbers for the collisions 84 Kr+112 Sn and 84 Kr+124 Sn at 35 MeV/nucleon, in a wide range of elements (up to Z ~ 20). The experimental data show that staggering effects (...)

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[in2p3-00782509] Effects of irradiation of energetic heavy ions on digital pulse shape analysis with silicon detectors

3 juillet 2015

The next generation of 4π detector arrays for heavy ion studies will largely use Pulse Shape Analysis to push the performance of silicon detectors with respect to ion identification. Energy resolution and pulse shape identification capabilities of silicon detectors under prolonged irradiation by (...)

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[in2p3-00656422] Particle identification using the (DELTA)E-E technique and pulse shape discrimination with the silicon detectors of the FAZIA project

3 juillet 2015

The response of silicon-silicon-CsI(Tl) and silicon-CsI(Tl) telescopes to fragments produced in nuclear interactions has been studied. The telescopes were developed within the FAZIA collaboration. The capabilities of two methods are compared: (a) the standard ΔE-E technique and (b) the digital (...)

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[hal-00461309] The prominent role of the heaviest fragment in multifragmentation and phase transition for hot nuclei

3 juillet 2015

The role played by the heaviest fragment in partitions of multifragmenting hot nuclei is emphasized. Its size/charge distribution (mean value, fluctuations and shape) gives information on properties of fragmenting nuclei and on the associated phase (...)

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[in2p3-00363510] New digital techniques applied to A and Z identification using pulse shape discrimination of silicon detector current signals

3 juillet 2015

Extending pulse shape discrimination (PSD) to digitized signals is one of the most promising methods to identify particles stopped in a detector. Using the CIME accelerator in the GANIL laboratory, a measurement campaign was done to collect data corresponding to different charges, masses and (...)

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[in2p3-00375772] Influence of the N/Z ratio on Disintegration Modes of Compound Nuclei

3 juillet 2015

Investigations into the role of the N/Z ratio on the decay modes of compound nuclei are presented. Characteristics of fragments with atomic number 6$\leq$Z$\leq$28 and light charged particles emitted in 78,82Kr+40Ca at 5.5 MeV/A reactions were measured at the GANIL facility using the (...)

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[in2p3-00875063] Isospin effects and symmetry energy studies with INDRA

3 juillet 2015

The equation of state of asymmetric nuclear matter is still controversial, as predictions at subsaturation as well as above normal density widely diverge. We discuss several experimental results measured in heavy-ion collisions with the INDRA array in the incident energy range 5-80 MeV/nucleon. (...)

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[in2p3-00691971] First measurements with the BEta deLayEd neutron detector (BELEN-20) at JYFLTRAP

3 juillet 2015

A prototype version of the BEta deLayEd Neutron detector, which is being developed for the FAIR/DESPEC experiment, has been used for the first time in an experiment at JYFL (Finland). This detector is based on 3He counters and its first run was primarily intended to commission the detector and (...)

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[in2p3-00858770] The european FAZIA initiative: a high-performance digital telescope array for heavy-ion studies

3 juillet 2015

The european Fazia collaboration aims at building a new modular array for charged product identification to be employed for heavy-ion studies. The elementary module of the array is a Silicon-Silicon-CsI telescope, optimized for ion identification also via pulse shape analysis. The achievement (...)

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[in2p3-00461302] Isospin diffusion in 58Ni-induced reactions at intermediate energies

3 juillet 2015

Isospin diffusion is probed as a function of the dissipated energy by studying two systems $^58$Ni+$^58$Ni and $^58$Ni+$^197$Au, over the incident energy range 52-74\AM. Experimental data are compared with the results of a microscopic transport model with two different parameterizations of the (...)

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[in2p3-00778551] Isospin transport in 84Kr + 112,124Sn collisions at Fermi energies

3 juillet 2015

Isotopically resolved fragments with Z =20 have been studied with high resolution telescopes in a test run for the FAZIA collaboration. The fragments were produced by the collision of a 84Kr beam at 35 MeV/nucleon with a n-rich (124Sn) and a n-poor (112Sn) target. The fragments, detected close (...)

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[in2p3-01067158] Quasiprojectile and intermediate velocity isotopic ratios for light fragments emitted in the Ar 36 +Ni 58 and Ni 58 +Ni 58 reactions between 32A and 84A MeV

3 juillet 2015

Isotopic ratios for light fragments (Z≤4 ) emitted by the quasiprojectile (QP) and the mid-rapidity (MR) sources are investigated by the use of a slightly asymmetric system (Ar 36 +Ni 58 ) and a symmetric one (Ni 58 +Ni 58 ) for six energies between 32A and 84A MeV and three semiperipheral (...)

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[in2p3-00587476] Decay of excited nuclei produced in $^{78,82}$Kr + $^{40}$Ca reactions at 5.5 MeV/nucleon

3 juillet 2015

Decay modes of excited nuclei are investigated in $^78,82$Kr + $^40$Ca reactions at 5.5 MeV/nucleon. Charged products were measured by means of the $4\pi$ INDRA array. Kinetic-energy spectra and angular distributions of fragments with atomic number 3 $\le Z \le$ 28 indicate a high degree of (...)

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[hal-00821065] Constrained caloric curves and phase transition for hot nuclei

3 juillet 2015

Simulations based on experimental data obtained from multifragmenting quasi-fused nuclei produced in central $^129$Xe + $^nat$Sn collisions have been used to deduce event by event freeze-out properties in the thermal excitation energy range 4-12 AMeV [Nucl. Phys. A809 (2008) 111]. From these (...)

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[in2p3-00812697] Long lifetime components in the decay of excited super-heavy nuclei

3 juillet 2015

For nuclear reactions in which super-heavy nuclei can be formed, the essential difference between the fusion process followed by fission and non-equilibrium processes leading to fissionlike fragments is the reaction time. Quite probable non-equilibrium processes, characterized by very short (...)

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[in2p3-00855210] The Fazia initiative: more powerful detectors for a more detailed investigation on the origin and the decay of charged fragments

3 juillet 2015

The main results of the R&D program of the FAZIA collaboration are described. The objective was to improve particle identication capabilities from solid-state telescopes made of Silicon detectors and CsI(Tl) scintillators in view of a new large acceptance apparatus to be used for heavy-ion (...)

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[hal-00454499] New scalings in nuclear fragmentation

3 juillet 2015

Fragment partitions of fragmenting hot nuclei produced in central and semiperipheral collisions have been compared in the excitation energy region 4-10 MeV per nucleon where radial collective expansion takes place. It is shown that, for a given total excitation energy per nucleon, the amount of (...)

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The Neutrons For Science facility at SPIRAL-2

6 mars 2013

The "Neutrons For Science" (NFS) facility will be a component of SPIRAL-2 laboratory under construction at Caen (France). The SPIRAL-2 facility will be dedicated to the production of high intensity of Radioactive Ions Beams (RIB). The high-power, superconducting driver LINAG (linear accelerator (...)

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The Neutrons for Science Facility at SPIRAL‐2

10 janvier 2012

The "Neutrons for Science" (NFS) facility will be a component of SPIRAL‐2, the future accelerator dedicated to the production of very intense radioactive ion beams, under construction at GANIL in Caen (France). NFS will be composed of a pulsed neutron beam for in‐flight measurements and (...)

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The Neutrons for Science Facility at SPIRAL‐2

10 janvier 2012

The "Neutrons for Science" (NFS) facility will be a component of SPIRAL‐2, the future accelerator dedicated to the production of very intense radioactive ion beams, under construction at GANIL in Caen (France). NFS will be composed of a pulsed neutron beam for in‐flight measurements and (...)

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The GUINEVERE Project for Accelerator Driven System Physics

9 septembre 2009

The GUINEVERE project is part of the EUROTRANS Integrated Project of the 6th EURATOM Framework Programme. It is mainly devoted to ADS on-line reactivity monitoring validation, sub-criticality determination and operational procedures (loading, start-up, shut-down, ...) as a follow-up of the MUSE (...)

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The GUINEVERE Project for Accelerator Driven System Physics

9 septembre 2009

The GUINEVERE project is part of the EUROTRANS Integrated Project of the 6th EURATOM Framework Programme. It is mainly devoted to ADS on-line reactivity monitoring validation, sub-criticality determination and operational procedures (loading, start-up, shut-down, ...) as a follow-up of the MUSE (...)

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GUINEVERE: Construction of a Zero-Power Pb ADS at Mol

7 mai 2009

The GUINEVERE project is running since 2007 and is part of the EUROTRANS Integrated Project of the 6th EURATOM Framework Programme. It consists first in the construction of a lead fast ADS mock-up at SCK-CEN Mol (Belgium) for the purpose of ADS subcriticality monitoring experiments, and beyond (...)

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GUINEVERE: Construction of a Zero-Power Pb ADS at Mol

7 mai 2009

The GUINEVERE project is running since 2007 and is part of the EUROTRANS Integrated Project of the 6th EURATOM Framework Programme. It consists first in the construction of a lead fast ADS mock-up at SCK-CEN Mol (Belgium) for the purpose of ADS subcriticality monitoring experiments, and beyond (...)

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Multifragmentation and spinodal decomposition of finite nuclear systems

28 avril 2009

A bulk effect in multifragmentation of very heavy fused systems has been experimentally evidenced. Such an effect is very well reproduced by a complete dynamical simulation of collisions in which multifragmentation occurs through the growth of density fluctuations in the unstable spinodal (...)

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Multifragmentation and spinodal decomposition of finite nuclear systems

28 avril 2009

A bulk effect in multifragmentation of very heavy fused systems has been experimentally evidenced. Such an effect is very well reproduced by a complete dynamical simulation of collisions in which multifragmentation occurs through the growth of density fluctuations in the unstable spinodal (...)

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Physics with the CHIMERA detector at LNS CATANIA methodology-experimental results - Future development

28 avril 2009

he new Charged Heavy Ion Mass and Energy Resolving Array CHIMERA was designed to significantly contribute to Multifragmentation studies in Heavy Ion collisions at Fermi energy (20A.MeV < E < 100A.MeV). The multi detector is presently being set up at LNS in Catania. On April 2000 the (...)

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Physics with the CHIMERA detector at LNS CATANIA methodology-experimental results - Future development

28 avril 2009

he new Charged Heavy Ion Mass and Energy Resolving Array CHIMERA was designed to significantly contribute to Multifragmentation studies in Heavy Ion collisions at Fermi energy (20A.MeV < E < 100A.MeV). The multi detector is presently being set up at LNS in Catania. On April 2000 the (...)

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Multifragmentation threshold in $^{93}Nb+${nat}Mg collisions at 30 MeV/nucleon

7 mai 2008

We analyzed the $^93Nb$ on $^natMg$ reaction at $30$ MeV/nucleon in the aim of disentangling binary sequential decay and multifragmentation decay close to the energy threshold, i.e. $\simeq 3$ MeV/nucleon. Using the backtracing technique applied to the statistical models GEMINI and SMM we (...)

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Multifragmentation threshold in $^{93}Nb+${nat}Mg collisions at 30 MeV/nucleon

7 mai 2008

We analyzed the $^93Nb$ on $^natMg$ reaction at $30$ MeV/nucleon in the aim of disentangling binary sequential decay and multifragmentation decay close to the energy threshold, i.e. $\simeq 3$ MeV/nucleon. Using the backtracing technique applied to the statistical models GEMINI and SMM we (...)

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A preliminary study on ternary fission in the $^{124}$Sn + $^{64}$Ni reaction at 35 MeV/A

22 août 2007

The projectile-like fragmentation in the $^124$Sn + $^64$Ni reaction at 35 MeV/A is investigated in the frame of ternary emission. With a very selective analysis of our data, we found consistency of our results with the concept of a ternary emission mechanism in heavy ions collisions at (...)

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A preliminary study on ternary fission in the $^{124}$Sn + $^{64}$Ni reaction at 35 MeV/A

22 août 2007

The projectile-like fragmentation in the $^124$Sn + $^64$Ni reaction at 35 MeV/A is investigated in the frame of ternary emission. With a very selective analysis of our data, we found consistency of our results with the concept of a ternary emission mechanism in heavy ions collisions at (...)

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(n,Xn) measurements at 96 MeV

5 juillet 2007

Double differential cross section for neutron production were measured in 96MeV neutrons induced reactions at the TSL laboratory in Uppsala (Sweden). Measurements for Fe and Pb targets were performed using simultaneously two independent setups: DECOI-DEMON and CLODIA-SCANDAL. The double (...)

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(n,Xn) measurements at 96 MeV

5 juillet 2007

Double differential cross section for neutron production were measured in 96MeV neutrons induced reactions at the TSL laboratory in Uppsala (Sweden). Measurements for Fe and Pb targets were performed using simultaneously two independent setups: DECOI-DEMON and CLODIA-SCANDAL. The double (...)

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A telescope for monitoring fast neutron sources

28 février 2007

In the framework of nuclear waste management, highly radiotoxic long-lived fission products and minor actinides are planned to be transmuted in a sub-critical reactor coupled with an intense external neutron source. The latter source would be created by a high-energy proton beam hitting a high (...)

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A telescope for monitoring fast neutron sources

28 février 2007

In the framework of nuclear waste management, highly radiotoxic long-lived fission products and minor actinides are planned to be transmuted in a sub-critical reactor coupled with an intense external neutron source. The latter source would be created by a high-energy proton beam hitting a high (...)

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Evaluation of excitation energy and spin from light charged particles multiplicities in heavy-ion collisions

5 janvier 2007

A simple procedure for evaluating the excitation energy and the spin transfer in heavy-ion dissipative collisions is proposed. It is based on a prediction of the GEMINI evaporation code : for a nucleus with a given excitation energy, the average number of emitted protons decreases with (...)

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Evaluation of excitation energy and spin from light charged particles multiplicities in heavy-ion collisions

5 janvier 2007

A simple procedure for evaluating the excitation energy and the spin transfer in heavy-ion dissipative collisions is proposed. It is based on a prediction of the GEMINI evaporation code : for a nucleus with a given excitation energy, the average number of emitted protons decreases with (...)

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Effect of the intermediate velocity emissions on the quasi-projectile properties for the Ar + Ni system at 95 A.MeV

4 janvier 2007

The quasi-projectile (QP) properties are investigated in the Ar+Ni collisions at 95 A.MeV taking into account the intermediate velocity emission. Indeed, in this reaction, between 52 and 95 A.MeV bombarding energies, the number of particles emitted in the intermediate velocity region is related (...)

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Effect of the intermediate velocity emissions on the quasi-projectile properties for the Ar + Ni system at 95 A.MeV

4 janvier 2007

The quasi-projectile (QP) properties are investigated in the Ar+Ni collisions at 95 A.MeV taking into account the intermediate velocity emission. Indeed, in this reaction, between 52 and 95 A.MeV bombarding energies, the number of particles emitted in the intermediate velocity region is related (...)

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A novel fast neutron detector for nuclear data measurements

24 novembre 2006

Accelerator driven system will use a heavy element target such as lead. Many calculations are available to simulate high-energy spallation neutron induced reactions, but little data are available for comparison with the simulations. In order to constrain the simulation tools we have measured (...)

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A novel fast neutron detector for nuclear data measurements

24 novembre 2006

Accelerator driven system will use a heavy element target such as lead. Many calculations are available to simulate high-energy spallation neutron induced reactions, but little data are available for comparison with the simulations. In order to constrain the simulation tools we have measured (...)

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A novel micromegas detector for in-core nuclear neutron flux measurement

14 novembre 2006

Future fast nuclear reactors designed for energy production and transmutation of nuclear wastes need new neutrons detectors able to measure the neutron flux over a large energy range from thermal energies to several MeV. A novel compact and very small detector, named Piccolo-Micromegas has been (...)

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A novel micromegas detector for in-core nuclear neutron flux measurement

14 novembre 2006

Future fast nuclear reactors designed for energy production and transmutation of nuclear wastes need new neutrons detectors able to measure the neutron flux over a large energy range from thermal energies to several MeV. A novel compact and very small detector, named Piccolo-Micromegas has been (...)

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Neutron flux measurements in the TRADE experiment : Critical configuration

18 septembre 2006

The TRiga Accelerator Driven Experiment (TRADE) to be performed in the existing TRIGA reactor of the ENEA Casaccia centre had the objective of coupling a spallation target, a proton accelerator and a sub-critical reactor core. On the way of the transmutation of minor actinides in dedicated (...)

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Neutron flux measurements in the TRADE experiment : Critical configuration

18 septembre 2006

The TRiga Accelerator Driven Experiment (TRADE) to be performed in the existing TRIGA reactor of the ENEA Casaccia centre had the objective of coupling a spallation target, a proton accelerator and a sub-critical reactor core. On the way of the transmutation of minor actinides in dedicated (...)

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Multifragmentation of a very heavy nuclear system (I): selection of a single-source events

10 juillet 2006

A sample of `single-source' events, compatible with the multifragmentation of very heavy fused systems, are isolated among well-measured $^155$Gd+$^nat$U 36AMeV reactions by examining the evolution of the kinematics of fragments with Z>=5 as a function of the dissipated energy and loss of (...)

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Multifragmentation of a very heavy nuclear system (I): selection of a single-source events

10 juillet 2006

A sample of `single-source' events, compatible with the multifragmentation of very heavy fused systems, are isolated among well-measured $^155$Gd+$^nat$U 36AMeV reactions by examining the evolution of the kinematics of fragments with Z>=5 as a function of the dissipated energy and loss of (...)

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Multifragmentation of a very heavy nuclear system (II) bulk properties and spinodal decomposition

10 juillet 2006

The properties of fragments and light charged particles emitted in multifragmentation of single sources formed in central 36AMeV Gd+U collisions are reviewed. Most of the products are isotropically distributed in the reaction c.m. Fragment kinetic energies reveal the onset of radial collective (...)

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Multifragmentation of a very heavy nuclear system (II) bulk properties and spinodal decomposition

10 juillet 2006

The properties of fragments and light charged particles emitted in multifragmentation of single sources formed in central 36AMeV Gd+U collisions are reviewed. Most of the products are isotropically distributed in the reaction c.m. Fragment kinetic energies reveal the onset of radial collective (...)

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Response of CsI(Tl) scintillators over a large range in energy and atomic number of ions (Part I) : recombination and $\delta$-electrons

7 juillet 2006

A simple formalism describing the light response of CsI(Tl) to heavy ions, which quantifies the luminescence and the quenching in terms of the competition between radiative transitions following the carrier trapping at the Tl activator sites and the electron-hole recombination, is proposed. The (...)

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Response of CsI(Tl) scintillators over a large range in energy and atomic number of ions (Part I) : recombination and $\delta$-electrons

7 juillet 2006

A simple formalism describing the light response of CsI(Tl) to heavy ions, which quantifies the luminescence and the quenching in terms of the competition between radiative transitions following the carrier trapping at the Tl activator sites and the electron-hole recombination, is proposed. The (...)

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New neutron detector based on micromegas technology for ADS projects

27 juin 2006

A new neutron detector based on Micromegas technology has been developed for the measurement of the simulated neutron spectrum in the ADS project. After the presentation of simulated neutron spectra obtained in the interaction of 140MeV protons with the spallation target inside the TRIGA core, (...)

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New neutron detector based on micromegas technology for ADS projects

27 juin 2006

A new neutron detector based on Micromegas technology has been developed for the measurement of the simulated neutron spectrum in the ADS project. After the presentation of simulated neutron spectra obtained in the interaction of 140MeV protons with the spallation target inside the TRIGA core, (...)

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Monitoring of 14 MeV neutrons

6 juin 2006

Long-lived fission products and minor actinides produced in nuclear power plants are the most radiotoxic nuclear wastes. They can be transmuted into stable nuclei or into nuclei with shorter lifetime thanks to the so-called Accelerator Driven Systems (ADS), consisting of the coupling of an (...)

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Monitoring of 14 MeV neutrons

6 juin 2006

Long-lived fission products and minor actinides produced in nuclear power plants are the most radiotoxic nuclear wastes. They can be transmuted into stable nuclei or into nuclei with shorter lifetime thanks to the so-called Accelerator Driven Systems (ADS), consisting of the coupling of an (...)

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Liquid-Gas Coexistence Region in Central Xe+Sn Reactions

18 octobre 2005

Charge partitions and distributions of fragments emitted in multifragmentation of fused systems produced in central collisions are studied over the incident energy range 32-50 MeV per nucleon. Most of the charged products are well identified thanks to the high performances of the INDRA 4pi (...)

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Liquid-Gas Coexistence Region in Central Xe+Sn Reactions

18 octobre 2005

Charge partitions and distributions of fragments emitted in multifragmentation of fused systems produced in central collisions are studied over the incident energy range 32-50 MeV per nucleon. Most of the charged products are well identified thanks to the high performances of the INDRA 4pi (...)

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Evidence for Spinodal Decomposition in Nuclear Multifragmentation

18 octobre 2005

Multifragmentation of a ``fused system\'\' was observed for central collisions between 32 MeV/nucleon 129Xe and natSn. Most of the resulting charged products were well identified thanks to the high performances of the INDRA 4pi array. Experimental higher-order charge correlations for fragments (...)

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Evidence for Spinodal Decomposition in Nuclear Multifragmentation

18 octobre 2005

Multifragmentation of a ``fused system\'\' was observed for central collisions between 32 MeV/nucleon 129Xe and natSn. Most of the resulting charged products were well identified thanks to the high performances of the INDRA 4pi array. Experimental higher-order charge correlations for fragments (...)

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Dynamical fission in $^{124}$Sn+$^{64}$Ni collision at 35A MeV

1er juillet 2005

Some properties of fast, nonequilibrium splitting of projectiles in the $^124$Sn+$^64$Ni reaction at 35A MeV were determined using the 4$\pi$ CHIMERA detector system. In particular the charge distributions, in- and out-of-plane angular distributions, and relative velocities of projectilelike (...)

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Dynamical fission in $^{124}$Sn+$^{64}$Ni collision at 35A MeV

1er juillet 2005

Some properties of fast, nonequilibrium splitting of projectiles in the $^124$Sn+$^64$Ni reaction at 35A MeV were determined using the 4$\pi$ CHIMERA detector system. In particular the charge distributions, in- and out-of-plane angular distributions, and relative velocities of projectilelike (...)

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Evolution of Fragment Distributions and Reaction Mechanisms for the Ar+Ni System from 32 to 95 A.MeV

24 juin 2005

Within the framework of flow and multifragmentation study, the 36Ar+58Ni 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 set-up, the main trends as well as the evolution of fragment (...)

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Evolution of Fragment Distributions and Reaction Mechanisms for the Ar+Ni System from 32 to 95 A.MeV

24 juin 2005

Within the framework of flow and multifragmentation study, the 36Ar+58Ni 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 set-up, the main trends as well as the evolution of fragment (...)

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Neutron to proton ratios of quasiprojectile and midrapidity emission in the ${58}$Ni-${58}$Ni reaction at 52 MeV/Nucleon

16 mars 2005

By combining data from a charged particle $^58$Ni+$^58$Ni experiment at 52 MeV/nucleon with an $^36$Ar+$^58$Ni experiment at 50 MeV/nucleon for which free neutrons have been detected, an increase in the neutron to proton ratio of the whole nuclear material at midrapidity has been experimentally (...)

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Neutron to proton ratios of quasiprojectile and midrapidity emission in the ${58}$Ni-${58}$Ni reaction at 52 MeV/Nucleon

16 mars 2005

By combining data from a charged particle $^58$Ni+$^58$Ni experiment at 52 MeV/nucleon with an $^36$Ar+$^58$Ni experiment at 50 MeV/nucleon for which free neutrons have been detected, an increase in the neutron to proton ratio of the whole nuclear material at midrapidity has been experimentally (...)

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Transverse velocity scaling in $^{197}$Au+$^{197}$Au fragmentation

25 février 2003

Invariant transverse-velocity spectra of intermediate-mass fragments were measured with the 4-pi multi-detector system INDRA for collisions of Au on Au at incident energies between 40 and 150 MeV per nucleon. Their scaling properties as a function of incident energy and atomic number Z are used (...)

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Study of intermediate velocity products in the Ar+Ni collisions between 52 and 95 A.MeV

7 février 2000

Intermediate velocity products in Ar+Ni collisions from 52 to 95 A.MeV are studied in an experiment performed at the GANIL facility with the 4$\pi$ multidetector INDRA. It is shown that these emissions cannot be explained by statistical decays of the quasi-projectile and the quasi-target in (...)

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