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R~1-10fm ~10 -21 -10 -15 sec. Femtoscopy and dynamics/ intermediate energies. G. Verde, INFN, Italy. Imaging “ Femtoscopy ” Transport models / Asy-EOS Complex particle correlations Our future. S.E. Koonin , PLB70 (1977) 43 S.Pratt et al ., PRC42 (1990) 2646. r 0. Kernel =.
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R~1-10fm ~10-21-10-15sec Femtoscopy and dynamics/ intermediate energies G. Verde, INFN, Italy • Imaging “Femtoscopy” • Transport models / Asy-EOS • Complex particle correlations • Our future
S.E. Koonin, PLB70 (1977) 43 S.Pratt et al., PRC42 (1990) 2646 r0 Kernel = • = Source function • If (not simultaneous) M. Lisa, PRL70 (1993) p-p correlations
FOPI Directional measurements at GSI energies • FOPI: central collisions @ 400 MeV/u • v ~ 2-3 fm • ALADiN: Target spectators Au+Au @ 1 GeV/u • < 20 fm/c Kotte et al., Eur. Phys. J.A 9 (1999) Schwarz, NPA 681 (2001) …these are short time scales
r0 Long-lived emissions at intermediate energies Secondary decays: enormous elongations (>104 fm/c…) Weak sensitivity to very long (Awes, Phys. Rev. Lett. 61, 1988) Directional correlations cannot tell the full story…
G. Verde et al., PRC65, 054609 (2002) Dynamical fast source (pre-equilibrium) Long-lived sources (evaporation, sec. decays, …) 1+R(q) q (MeV/c) Angle-averaged correlations: information content Ytotal=Dynamical + Sec. Decays Yfast + Yslow
G. Verde et al., PRC65, 054609 (2002) 4 p-p 3 1+R(q) Width (MeV/c) 2 p-p 1 q (MeV/c) Source size (fm) 1 0 20 40 60 80 100 Peak B 1+R(q) Width (MeV/c) Peak B Peak A d- d- Peak A Source size (fm) q (MeV/c) “Femtoscopes”… from the widths Angle-averaged
dynamical source (pre-eq.) 14N+197Au E/A=75 MeV evap. sources (sec. decays) Source size G. Verde et al., PRC65, 069604 (2002) P. Danielewicz, D.A. Brown Imaging at intermediate energies Ytotal=Dynamical + Sec. Decays Yfast + Yslow
What physics from imaging Sizes from width of peaks Relative contributions from long-lived emissions from integral of source (peak height) Handle on secondary decays! Entire source profile: probes of transport models (EOS, Asy-EOS,…)
Central Collisions Early comparisons to BUU failed: Long-lived emitting sources not handled properly D.O. Handzy et al., PRL 75 (1995) 2916 Probing transport properties? USE IMAGED SOURCE TO RENORMALIZE BUU SOURCES
Ar+Sc central G. Verde et al., Phys. Rev. C67, 034606 (2003) Imaged S(r) vs BUU S(r) E/A=120 MeV Imaging Data Models S(r) (fm-3) BUU red sNN BUU free sNN r (fm) Source shape sensitive to NN q e Imaging and transport Handzy, Lisa (1994)
Imaged sources S(r) Size (fm) S(r) Apart • Size increases with nr. of participants • Dynamical features r (fm) pp source systematics in central collisions • No E/A dependence What do transport models say about it?
Kr+Nb bred<0.4 E/A=100 MeV • Imaged sources reproduced by BUU with red NN Imaging data BUU free NN S(r) (a.u.) BUU red NN • E/A independence • Apart dependence Kr+Nb BUU E/A=120 MeV 100 MeV 70 MeV E/A=70 MeV Ar+Sc BUU E/A=150 MeV 100 MeV S(r) (a.u.) Probing dynamical early stages? Back-tracing p emission in BUU r (fm) Central collisions - Imaging vs BUU G. Verde, B. Barker,P. Danielewicz (2008)
112Sn+124Sn E/A=50 MeV bred=0-0.4 dN/dt PT/m > 0.2 PT/m > 0.3 time (fm/c) Protons emission time and transverse momentum Early Late
Early pp emitting source PT > 0.3 PT > 0.2 No PT gate pp sources S(r) (fm-3) r (fm) High PT: shorter emission times and smaller source sizes “Back-tracing” p emission as it is probed by HBT
Emitting source functions Emmission times of neutrons and protons Density dependence of symmetry potential in EOS IBUU: 52Ca+48Ca E/A=80 MeV Asy-Stiff Asy-Soft Asy-stiff Asy-Soft Vsym(MeV) S(r) (fm-3) 0 Asy-Stiff Asy-soft Lie-Wen Chen et al., PRL (2003), PRC(2005) r (fm) Emission times and Asy-EOS
Asy-stiff 1+R(q) Asy-soft q (MeV/c) CsI Si strips X-Y Angular resolution ! Isotopic effects on p-p imaging40,48Ca + 40,48Ca E/A=80 MeV Collaboration: MSU, IU, WU INFN Catania GANIL HiRA High angular resolution required: accessing low q-values…
Em. source more localized in N=Z than in N>Z 40Ca+40Ca N/Z=1 E/A=80 MeV central 40Ca+40Ca N/Z=1 S(r) (a.u.) 1+R(q) 48Ca+48Ca N/Z=1.4 S(r) (a.u.) 48Ca+48Ca N/Z=1.4 r (fm) S(r) (a.u.) prelim r (fm) Sensitivity to Esym(),stopping, NN, asy-transport (IBUU)… in progress q (MeV/c) r (fm) N/Z effects on p-p correlation functions
neutron-proton … in memory of Tano Lanzano’… Neutron-proton correlation functions Ghetti et al,PRC 69 (2004) 031605 Protons Neutrons Accessing emission chronology - high sensitivity to Asy-EOS Verde, Chbihi, Ghetti, Helgesson, EPJA 30, 2006
d-a p-p 1+R(E*) E*(MeV) a-6Li Beyond pp correlations… • Chronology and Hierarchy: different particles emitted at different times • Non-identical particle correlations relevant to pp correlations • IMF emission times: talk by E. De Filippo tomorrow stay tuned!
p-, p + A 8.0, 8.2, 9.2, 10.2 GeV/c Kr + Au Surf Bulk Miniball data, E. Cornell et al., PRL75 (1995) 1475 ISiS data, L. Beaulieu et al., PRL84 (2000) 5971 From surface to bulk emission (Liquid-gas phase transition?) Emission time decreases with velocity Evolutionary fragment emission mechanisms (EES predictions) IMF emission times
d- correl 1+R(q) Distortions due to position/momentum correlations Second peak attenuated q (MeV/c) Light complex particles • Dominated by nuclear short-range interaction
Thermal Position dependent velocity fields: q (MeV/c) r (fm) r-q correlations! (r-P correlations!) • S = S(r,q) • Line-shape of R(q) distorted and depending on T Thermal+Collective q (MeV/c) r (fm) Collective motion and correlations G. Verde et al., Physics Letters B653, 12 (2007)
d- p-p Xe+Au E/A=50 MeV bred<0.3 Ed>40MeV E>45MeV Ep>30 MeV 1+R(q) 1+R(q) r0=5.6 fm r0=2.2 fm fast fast No Teffcorrection 20<Ed<40MeV 25<E<45MeV 15 <Ep<30 MeV 1+R(q) 1+R(q) r0=9.4 fm r0=6 fm medium medium Small Teff correction 0 <Ep<15 MeV 0<Ed<20MeV 0<E<25MeV 1+R(q) 1+R(q) r0=14 fm r0=9 fm slow slow Large Teff correction q (MeV/c) q (MeV/c) dvs pp radii
16 pp 14 14.00 12 d 10 9.40 9.00 Sizes (fm) 8 6 6.00 5.60 4 2.20 2 0 Ecm gates Sizes: pp vs d Xe+Au E/A=50 MeV central d- sources more localized than p-p sources Different particles emitted at different time stages (hierarchy) EES scenario (W. Friedmann)
10C* ---> p+p+ 8B*---> p+7Be F. Grenier, A. Chbihi, R. Roy, G. Verde et al., NPA, in print T. Wanpeng et al., PRC (2004) C+Mg LASSA data Relative heights of peak heights sensitive to spin of 8Be states INDRA Ek(MeV) Probe sequential decays 10C-->9B+p vs 10C-->6Be+ HIC as a spectroscopic tool • Several unbound states are produced in each collision - reconstructed with correlations
Conclusions • Femtoscopy and imaging • Sizes, contributions pre-eq/evap • Probing transport theories and back-tracing particle emissions • Isotopic effects (N/Z) to access Asy-EOS - preliminary results on Ca+Ca data • Extend to several particle species - reveal hierarchy and chronology
Active projects • Chimera and Indra + Silicon strips (INFN, GANIL) improving angular resolution • Fazia (Italy, France, Poland, Romania, Spain, UK, India) - 4 detector with high isotopic resolution, PSA and digitalization, low thresholds - well suited to future Spiral2 experiments • HiRA, LASSA+First (USA) presently exploring isospin and HBT physics
Acknowledgements • NSCL/MSU(P. Danielewicz, W.G. Lynch, M.B. Tsang, Wanpeng Tan, K. Gelbke, B. Barker, REU students) • HiRA groups (IU, MSU, WU) • LLNL (D.A. Brown) • INDRA group (A. Chbihi, J. Frankland et al.) • Laval University(F. Grenier, R. Roy)