5th International Symposium on Nuclear Symmetry Energy NuSYM15, June 29 - July 2, 2015 Kraków, POLAND

Enrico De Filippo

Sensitivity of N/Z ratio in projectile break-up of isobaric systems: a new probe for symmetry energy?

E. De Filippo$^1$, L. Acosta$^{3,10}$, L. Auditore$^{4}$, V. Baran$^{5}$, T. Cap$^{9}$, G. Cardella$^{1}$, M. Colonna$^{3}$, L. Francalanza$^{2,3}$, B. Gnoffo$^{1,2}$, G. Lanzalone$^{3,6}$, I. Lombardo$^{7}$, G. Marquínez-Durán$^{3,10}$, C. Maiolino$^{3}$, T. Minniti${3}$, S. Norella$^{4}$, A. Pagano$^{1}$, E.V. Pagano$^{2,3}$, M. Papa$^{1}$, E. Piasecki$^{8,10}$, S. Pirrone$^{1}$, G. Politi$^{2,1}$, F. Porto$^{2,3}$, L. Quattrocchi$^{4}$, F. Rizzo$^{2,3}$, E. Rosato$^{7}$, P. Russotto$^{1}$, A. Trifirò$^{4}$, M. Trimarchi$^{4}$, G. Verde$^{1}$, M. Vigilante$^{7}$, K. Siwek-Wilczynska$^{8}$, J. Wilczynski$^{9}$

$^{1}$INFN, Sezione di Catania, Italy
$^{2}$Dipartimento di Fisica e Astronomia, Università di Catania, Italy
$^{3}$INFN, Laboratori Nazionali del Sud, Catania, Italy
$^{4}$INFN, Gruppo collegato di Messina and Dip. Fisica, Univ. Messina, Italy
$^{5}$Physics Faculty, University of Bucharest, Romania
$^{6}$Università Kore, Enna, Italy
$^{7}$INFN, Sezione di Napoli and Dip. Fisica, Università di Napoli, Italy
$^{8}$Heavy Ion Laboratory, University of Warsaw, Poland
$^{9}$National Centre for Nuclear Research, Otwock-Swierk, Poland
$^{10}$Departamento de Fisica Aplicada, Huelva, Spain

The time scale of fragment production in nuclear reactions at medium energies is a key concept to pin down the role of the isospin degree of freedom and symmetry energy in finite matter. Recently, in the reactions $^{124}$Sn+$^{64}$Ni and $^{112}$Sn+$^{58}$Ni at 35 A.MeV [1] it has been shown that while the statistical (sequential decay) emission of Intermediate Mass Fragment (IMF) assumes the same cross section for the two systems as a function of the IMF charge Z of the emitted projectile-like fragments, the dynamical (prompt decay) IMF emission cross section is enhanced for the neutron rich system, pointing to an isospin effects related to the N/Z of the entrance channel. Indeed neutron richness enhances the probability of multiple cluster formation. In order to progress in this investigation, the reactions $^{124}$Xe+$^{64}$Zn and $^{124}$Xe+$^{64}$Ni at 35 A.MeV (InKiIsSy experiment, Inverse Kinematic Isobaric Systems), have been investigated at LNS, using the 4π detector CHIMERA. These new systems are “isobaric” with respect to the previous $^{124}$Sn + $^{64}$Ni reaction studied in both direct and inverse kinematics. Preliminary results of the InkiIsSy experiment show similar effects when comparing the reactions induced by the Xe beam on the two different targets. In the InKiIsSy experiment, for the first time, a block of four telescopes, DSSSD ΔE-E and CsI(Tl) - prototype of the new FARCOS femtoscope high resolution array - has been used in coincidence with CHIMERA. Exploring the physics of fast break-up or dynamical fission as a function of the isospin of the entrance channel is an attractive topic of heavy ions physics with radioactive beams that are expected to be available in the next future at SPES and SPIRAL2 facilities [2].

[1] P. Russotto et al., Phys. Rev. C 91, 014610 (2015).
[2] EXOCHIM collaboration, SPES LoI (2014)