Post on 18-Jan-2016
High-resolution experiments on High-resolution experiments on
projectile fragments – A new projectile fragments – A new
approach to the properties of approach to the properties of
nuclear matternuclear matter
A. Kelić1, J. Benlliure2, T. Enqvist1, V. Henzl1,
D. Henzlova1, J. Pereira1, M. V. Ricciardi1,
K.-H. Schmidt1, Ch. Schmitt1, O. Yordanov1
1GSI – Darmstadt2Univ. Santiago de Compostela, Spain
Why studying nuclear-matter Why studying nuclear-matter properties?properties?
Fundamental questions:
- How does the nuclear matter „look like“?
- How does it behave under extreme conditions:
high densities and temperatures, extreme N/Z ratio...?
Static properties of NM: Incompressibility, phase transitions, excitation of nucleons ...
Dynamic properties of NM: Viscosity, momentum dependence of nuclear mean field ...
Problem: Most of the observables are sensitive to different and often competing effects!
New observables:
- Spectator response to the participant blast (MV. Ricciardi et al, PRL90 (03) 212302) Momentum dependence of the nuclear mean field.
- Isospin thermometer (K.H. Schmidt et al., NPA 710 (02) 157) Thermal instabilities in NM.
- Partial fission cross sections and width of charge distributions (B. Jurado et al. subm. to PRL) Viscosity of NM.
-TOF (F2F4): TOF ~ 100 ps
- x(F2), x(F4): x ~ 3 mm
- B1, B2: B/B ~ 10-4
(B)/(B) ~ 5 · 10-4,
(· )/(· ) ~ 2.5 · 10-3,
A/A ~ 2.5 · 10-3.e
cmo
Z
AB
After identification of Z and A (Z and A are integer numbers) B provides velocity with high precision resolution of 510-4 in · !
ExperimentExperiment
But: No correlation to other products, low acceptance for fission fragments and very light fragmentation residues.
238U+Pb 1AGeV
T. Enqvist et al., NPA658(99)47.
Experimental results – Experimental results – general viewgeneral view
Data analysed by: M. Bernas (NPA725(03)215), M.V. Ricciardi (PhD), J. Taïeb (NPA724(03)413).
238U + protons 1AGeV
Systematic information on nuclide distributions and velocities.
Uncertainties:
- Cross sections: 3% statistical, 9-15 % systematical.
- Momentum: p/p ~ 510-4.
- N/Z ratio: 1 %.
Experimental results – Experimental results – specificspecific
Investigation of the momentum-dependent mean
field (PRL 90 (2003) 212302).
PRL 90 (2003) 212302
Projectile-spectator
Target-spectator
Participants
Present statusPresent status and and outlookoutlook
Isospin thermometer : 136Xe(1 A GeV ) + Pb analysis in progress, 124Xe(1 A GeV ) + Pb measurements at this moment. PhD D. Henzlova.
EOS : Au + Au and Sn + Sn experiments in preparation. PhD V. Henzl.
Viscosity of nuclear matter : Fission data of 60 radioactive nuclei ranging from U to Ac analysed, model calculations in progress. Ch. Schmitt