isospin dependence of intermediate mass fragments in 124sn, 124xe + 124sn, 112sn d. v. shetty, a....
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Isospin Dependence of Intermediate Mass Fragments in 124Sn, 124Xe + 124Sn, 112SnIsospin Dependence of Intermediate Mass Fragments in 124Sn, 124Xe + 124Sn, 112Sn
D. V. Shetty, A. Keksis, E. Martin, A. Ruangma, G.A. Souliotis, M. Veselsky, E.M. Winchester, S.J. Yennello, K.
Hagel, Y.G. Ma, M. Murray, J.B. Natowitz, L. Qin, P. Smith, R. Wada, J. Wang, M. Cinausero, E. Fioretto, G. Prete, D.
Fabris, M. Lunardon, G. Nebbia, V. Rizzi, G. Viesti, J. Cibor, Z. Majka, P. Staszel, R. Alfarro, A. Martinez-Davalos, A.
Menchaca-Rocha, Y. El Masri and T. Keutgen
D. V. Shetty, A. Keksis, E. Martin, A. Ruangma, G.A. Souliotis, M. Veselsky, E.M. Winchester, S.J. Yennello, K.
Hagel, Y.G. Ma, M. Murray, J.B. Natowitz, L. Qin, P. Smith, R. Wada, J. Wang, M. Cinausero, E. Fioretto, G. Prete, D.
Fabris, M. Lunardon, G. Nebbia, V. Rizzi, G. Viesti, J. Cibor, Z. Majka, P. Staszel, R. Alfarro, A. Martinez-Davalos, A.
Menchaca-Rocha, Y. El Masri and T. Keutgen
Cyclotron Institute, Texas A&M University INFN Laboratori Nazionali di Legnaro, Legnaro, Italy
INFN Dipartimento di Fisica, Padova, Italy Jagellonian University, Krakow, Poland UNAM, Mexico City, Mexico UCL, Louvain-la-
Neuve, Belgium
Cyclotron Institute, Texas A&M University INFN Laboratori Nazionali di Legnaro, Legnaro, Italy
INFN Dipartimento di Fisica, Padova, Italy Jagellonian University, Krakow, Poland UNAM, Mexico City, Mexico UCL, Louvain-la-
Neuve, Belgium
Isospin asymmetric matter behaves differently from
symmetric nuclear matter
Theoretical Predictions Isospin Equilibration
Isospin Fractionation Midrapidity
Emission ….
Expt Observables Fragment yield dist, Isotopic & isobaric yields, energy spectras
……
Reactions Studied :Reactions Studied :
124Xe + 112Sn (N/Z) = 1.27 124Sn + 112Sn (N/Z) = 1.36 124Xe + 124Sn (N/Z) = 1.38 124Sn + 124Sn (N/Z) = 1.48
Beam Energy :Beam Energy :
28 MeV/nucleon
Detectors :Detectors :
NIMROD, 4 charged particle array
Isospin Dependence of the Fractional YieldIsospin Dependence of the Fractional Yield
Nearly symmetric isotopic yield distribution
Nearly symmetric isotopic yield distribution
System with lowest N/Z produce the highest fraction of n-deficient isotopes
System with lowest N/Z produce the highest fraction of n-deficient isotopes
System with highest N/Z produce highest fraction of n-rich isotopes
System with highest N/Z produce highest fraction of n-rich isotopes
Isospin Dependence of Isotopic Yield Ratio and Angular Evolution
Isospin Dependence of Isotopic Yield Ratio and Angular Evolution
Angular evolution of isotopic yields depends on
the N/Z of the system
Angular evolution of isotopic yields depends on
the N/Z of the system
Isospin equilibration
at central angle
Isospin equilibration
at central angle
Isospin Distillation and Fragment < N/Z > Dependence
Isospin Distillation and Fragment < N/Z > Dependence
Excess neutrons become available in the form of light and n-rich
clusters
Excess neutrons become available in the form of light and n-rich
clusters
Decrease in <N/Z> with increasing Z supports the idea of two phase split of
nuclear matter (distillation)
Decrease in <N/Z> with increasing Z supports the idea of two phase split of
nuclear matter (distillation)
Isospin Dependence of Isobaric Yield RatiosIsospin Dependence of Isobaric Yield Ratios
Energy Spectra Dependence of the IsotopesEnergy Spectra Dependence of the Isotopes
3 Source fit for Li fragments3 Source fit for Li fragments
Parallel Velocity Distribution as Function of Centrality
Parallel Velocity Distribution as Function of Centrality
Mid-Rapidity Emission of the Light FragmentsMid-Rapidity Emission of the Light Fragments
Centrality Dependence of
the Relative yield
Centrality Dependence of
the Relative yield
1. Fractional yield of the n-rich isotopes increase and those of n-deficient isotopes decrease with increasing N/Z of the system.
2. Isotopic and isobaric yield ratios increase linearly with N/Z of the composite system indicating near equilibration along central angle.
3. Neutron content of the light cluster increase significantly with decreasing temperature.
4. <N/Z> of the fragments indicate excess neutrons becoming available to light and n-rich clusters.
5. Energy spectras for different isotopes of light fragments are appreciably different.
6. Rapidity dist. as a function of centrality show heavier isotopes being emitted closer to midrapidity region.
Conclusions :