Experimental study of the ${}^{40,48}$Ca+ ${}^{40,48}$Ca reactions at 35 MeV/nucleon

Abstract

In this article we investigate ${}^{40,48}$Ca+${}^{40,48}$Ca peripheral and semi-peripheral reactions at 35 MeV/nucleon. Data were obtained using the unique coupling of the VAMOS high acceptance spectrometer and the INDRA charged particle multidetector.The spectrometer allowed high resolution measurement of charge, mass and velocity of the cold projectile-like fragment (PLF), while the INDRA detector recorded coincident charged particles with nearly $4\pi$ acceptance.The measured isotopic composition of the PLF identified in VAMOS and the average light charged particle (LCP) multiplicities are promising observables to study the isospin diffusion.The detection of the PLF in coincidence with LCP allows the reconstruction of the mass, charge and excitation energy of the associated initial quasi-projectile nuclei (QP), as well as the extraction of apparent temperatures.We investigate the suitability of the isoscaling method with the PLF and the experimental reconstructed QP.The extracted $\alpha$ and $\Delta$ isoscaling parameters present a dependence on the considered system combination that could justify their use as a surrogate for isospin asymmetry in isospin transport studies.The reconstruction of the QP allows to observe an evolution of the $\alpha /\Delta$ with the size of the QP, the latter being consistent with a strong surface contribution to the symmetry energy term in finite nuclei. This leads to the conclusion that the reconstruction of the primary source is mandatory for the study of the symmetry energy term based on the isoscaling method for such reactions.

References in corpus (18)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• Constraining Neutron-Star Matter with Microscopic and Macroscopic Collisions
• Results of the ASY-EOS experiment at GSI: The symmetry energy at suprasaturation density
• Constraints on the Symmetry Energy Using the Mass-Radius Relation of Neutron Stars
• Isospin Diffusion and Equilibration for Sn+Sn collisions at E/A=35 MeV
• Asymmetry dependence of proton correlations
• Liquid-Gas phase transition in nuclei
• Tracing the evolution of the symmetry energy of hot nuclear fragments from the compound nucleus towards multifragmentation
• Thermal and Chemical Freeze-out in Spectator Fragmentation
• Isospin Distillation with Radial Flow: a Test of the Nuclear Symmetry Energy
• Isospin diffusion in semi-peripheral ${}^{58}Ni$ + ${}^{197}Au$ collisions at intermediate energies (II): Dynamical simulations
• Isoscaling as a measure of Symmetry Energy in the Lattice Gas Model
• Systematic Matter and Binding-Energy Distributions from a Dispersive Optical Model Analysis
• Isospin diffusion measurement from the direct detection of a Quasi-Projectile remnant
• Isospin dependent thermodynamics of fragmentation
• Multifragmentation and the symmetry term of the nuclear equation of state
• Effect of secondary decay on isoscaling: Results from the canonical thermodynamical model
• Influence of fast emissions and statistical de-excitation on the isospin transport ratio

Cited by in corpus (5)

• Isoscaling in central Sn+Sn collisions at 270 MeV/u
• Experimental study of the isospin transport with 40,48 Ca+ 40,48 Ca reactions at 35 MeV/nucleon
• Fast trajectory reconstruction techniques for the large acceptance magnetic spectrometer VAMOS++
• Isospin diffusion from ${}^{40,48}$Ca${+}^{40,48}$Ca experimental data at Fermi energies: Direct comparisons with transport model calculations
• Study of quasi-projectile properties at Fermi energies in 48Ca projectile systems