Abstract
Isospin transport phenomena in dissipative heavy ion collisions have been investigated at Fermi energies with a beam of 84Kr at 35AMeV. A comparison of the <N>/Z of light and medium products forward-emitted in the centre of mass frame when the beam impinges on a n-poor 112Sn and a n-rich 124Sn targets is presented. Data were collected by means of a three-layer telescope with very good performances in terms of mass identification (full isotopic resolution up to Z about 20 for ions punching through the first detector layer) built by the FAZIA Collaboration and located just beyond the grazing angle for both reactions. The <N>/Z of the decay products emitted when the n-rich target is used is always higher than that associated to the n-poor one. Since the detector was able to measure only fragments coming from the QuasiProjectile decay and/or neck emission, the observed behaviour can be ascribed to the isospin diffusion, driven by the isospin gradient between QuasiProjectile and QuasiTarget. Moreover, for light fragments the <N>/Z as a function of the lab velocity of the fragment increases when we move from the QuasiProjectile velocity to the centre of mass (neck zone). This effect can be interpreted as an evidence of isospin drift driven by the density gradient between the QuasiProjectile zone (at normal density) and the more diluted neck zone.
Highlights
In this work we present some evidences of isospin diffusion and isospin drift observed by the FAZIA Collaboration for two reactions with the same beam, 84Kr at 35AMeV, and two different targets, the “n-poor” 112Sn and the “n-rich” 124Sn
The identification procedure uses the standard ∆E - E technique for particles punching through the first Si layer, obtaining full isotopic resolution in a region up to now accessible only by means of spectrometers
For particles stopped in the first Si layer, full charge identification can be obtained by means of Pulse Shape Analysis techniques if the ions have a range in Si greater than 30μm
Summary
The FAZIA Collaboration [10] has started to investigate these processes [11], thanks to the good capabilities in terms of isotopic resolution of the developed three-layer telescopes (full isotopic resolution up to Z ∼ 20 − 23 for ions punching through the first detector layer). In this work we present some evidences of isospin diffusion and isospin drift observed by the FAZIA Collaboration for two reactions with the same beam, 84Kr at 35AMeV, and two different targets, the “n-poor” 112Sn and the “n-rich” 124Sn. The experiment was performed at LNS of INFN in Catania (Italy) by means of the beam delivered by the CS Superconducting Cyclotron.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
