Constraining the density dependence
of the symmetry
energy at low density using new observables from neck
fragmentation mechanism, E. De Filippo for the EXOCHIM
collaboration, INFN
Catania, Italy − We present
comparisons between experimental data for the systems 35 A. MeV ^{124}Ni
+
^{64}Ni (neutron rich) and ^{112}Sn + ^{58}Ni
(neutron
poor) studied in inverse (Reverse experiment) and direct
kinematics
(Timescale experiment) and Stochastic Mean Field (SMF) + GEMINI
calculations. We have
correlated the emission timescale at
mid-velocity of intermediate mass fragments (IMF) with their
isotopic
composition: prompt emitted particles show larger value of
asymmetry, stronger
angular anisotropies and reduced odd-even staggering effects in
distributions
respect those produced in sequential emission. By comparison the data
with calculations we
show that these new observables add valuable constraint on the
symmetry energy term
of EOS at subsaturation density and can constitute a robust probe
for dynamical
models (SMF, QMD) predictions.