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DPG, 11.03.08
Fragment formation in low energy proton-induced reactions Fragment formation in low energy proton-induced reactions within a hybrid BUU+SMM approachwithin a hybrid BUU+SMM approach
Th. Gaitanos, H. Lenske, U. MoselTh. Gaitanos, H. Lenske, U. Mosel
IntroductionIntroduction
Theoretical descriptionTheoretical descriptionNon-equlibrium stage (GiBUU)Asymptotic equilibrium stage (SMM)Hybrid approach (GiBUU+SMM)
ApplicationsBenchmark p+X@SIS/GSI energies
Final remarksFinal remarks
DPG, 11.03.08
Introduction…Introduction…Introduction…Introduction…
Spallation reactions („small“ excitation of residual nucleus resp. to its ground state)
useful tool to theoretically study/test long-time scales of fragmentation process
Spallation reactions („small“ excitation of residual nucleus resp. to its ground state)
useful tool to theoretically study/test long-time scales of fragmentation process
ApplicationsApplications
•Study of hypernuclei (2nd talk): HIC@SIS (HypHI)
•In future: PANDA (pbar+X), J-PARC (p+X@50GeV, X+X@20AGeV)
ApplicationsApplications
•Study of hypernuclei (2nd talk): HIC@SIS (HypHI)
•In future: PANDA (pbar+X), J-PARC (p+X@50GeV, X+X@20AGeV)
Theor. description of Low energy hadron-induced Theor. description of Low energy hadron-induced reactionsreactions
Theor. description of Low energy hadron-induced Theor. description of Low energy hadron-induced reactionsreactions
Non-(pre-)equilibrium first phaseNon-(pre-)equilibrium first phaseNon-(pre-)equilibrium first phaseNon-(pre-)equilibrium first phase Asymptotic final stateAsymptotic final stateAsymptotic final stateAsymptotic final state
Equilibrated source with small excitation
Statistical multifragmentation models
Equilibrated source with small excitation
Statistical multifragmentation models
Highly excited system
Dynamical transport (BUU, QMD, INC)
Highly excited system
Dynamical transport (BUU, QMD, INC)
„„Hybrid“ models Hybrid“ models (BUU+SMM)(BUU+SMM)
DPG, 11.03.08
Theoretical description…Theoretical description…Theoretical description…Theoretical description…
Initial non-equilibrium stageInitial non-equilibrium stage
•Relativistic transport equation of Boltzmann-type
•Giessen-Boltzmann-Uehling-Uhlenbeck (GiBUU)
Initial non-equilibrium stageInitial non-equilibrium stage
•Relativistic transport equation of Boltzmann-type
•Giessen-Boltzmann-Uehling-Uhlenbeck (GiBUU)
Asymptotic equilibrated stageAsymptotic equilibrated stage
•Fission/spallation, evaporation, multifragmentation… (with increasing excitation)
•Statistical determination of partial decay widths Monte-Carlo method
(basic method similar to numerical treatment of collisions in transport approaches)
Asymptotic equilibrated stageAsymptotic equilibrated stage
•Fission/spallation, evaporation, multifragmentation… (with increasing excitation)
•Statistical determination of partial decay widths Monte-Carlo method
(basic method similar to numerical treatment of collisions in transport approaches)
E*
Ai,Zi
E*
Ai,Zi
E*-
Ad,Zd
E*-
Ad,Zd
j,j,
AiAi Ad+nAd+n
(http://theorie.physik.uni-giessen.de/GiBUU)(http://theorie.physik.uni-giessen.de/GiBUU)(http://theorie.physik.uni-giessen.de/GiBUU)(http://theorie.physik.uni-giessen.de/GiBUU)
SMM code: Botvina & Mishustin, PR257(´95) SMM code: Botvina & Mishustin, PR257(´95) 133133SMM code: Botvina & Mishustin, PR257(´95) SMM code: Botvina & Mishustin, PR257(´95) 133133
DPG, 11.03.08
Benchmark: Benchmark: [email protected][email protected] (properties of fragmenting source)… (properties of fragmenting source)…Benchmark: Benchmark: [email protected][email protected] (properties of fragmenting source)… (properties of fragmenting source)…
e-Print: arXiv: 0712.3292 (almost accepted…)e-Print: arXiv: 0712.3292 (almost accepted…)e-Print: arXiv: 0712.3292 (almost accepted…)e-Print: arXiv: 0712.3292 (almost accepted…)
Definition of residual nucleus: <sat/100.Definition of residual nucleus: <sat/100.
Non-Equilibrium dynamics within GiBUU until system(s) approach local equilibrium at t=tf
Determination of A,Z and Eexc at time tf, and then apply SMM
Non-Equilibrium dynamics within GiBUU until system(s) approach local equilibrium at t=tf
Determination of A,Z and Eexc at time tf, and then apply SMM
DPG, 11.03.08
Benchmark: Benchmark: [email protected][email protected] (global characteristics)… (global characteristics)…Benchmark: Benchmark: [email protected][email protected] (global characteristics)… (global characteristics)…
Charge distribution…Charge distribution…
Mass distribution…
Mass distribution…
e-Print: arXiv: 0712.3292 (almost accepted…)e-Print: arXiv: 0712.3292 (almost accepted…)
Data: F. Rejmund et. al., NPA683(´01) 540Data: F. Rejmund et. al., NPA683(´01) 540
J. Benlliure et. al., NPA683(´01) 513J. Benlliure et. al., NPA683(´01) 513
e-Print: arXiv: 0712.3292 (almost accepted…)e-Print: arXiv: 0712.3292 (almost accepted…)
Data: F. Rejmund et. al., NPA683(´01) 540Data: F. Rejmund et. al., NPA683(´01) 540
J. Benlliure et. al., NPA683(´01) 513J. Benlliure et. al., NPA683(´01) 513
DPG, 11.03.08
Benchmark: Benchmark: p+Xp+X reactions (details)… reactions (details)…Benchmark: Benchmark: p+Xp+X reactions (details)… reactions (details)…
e-Print: arXiv: 0712.3292 (almost accepted…)e-Print: arXiv: 0712.3292 (almost accepted…)
Data: F. Rejmund et. al., NPA683(´01) 540Data: F. Rejmund et. al., NPA683(´01) 540
J. Benlliure et. al., NPA683(´01) 513J. Benlliure et. al., NPA683(´01) 513
e-Print: arXiv: 0712.3292 (almost accepted…)e-Print: arXiv: 0712.3292 (almost accepted…)
Data: F. Rejmund et. al., NPA683(´01) 540Data: F. Rejmund et. al., NPA683(´01) 540
J. Benlliure et. al., NPA683(´01) 513J. Benlliure et. al., NPA683(´01) 513
DPG, 11.03.08
Final remarks & Outlook…Final remarks & Outlook…
Low-energy proton-induced reactionsLow-energy proton-induced reactions Residual system under stable conditions no compression/expansion effects, no radial flow effects Wide selection of experimental data Useful tool to study transport models including fragmentation
Hybrid approach (GiBUU+SMM)Hybrid approach (GiBUU+SMM) Initial stage: StableStable ground state pre-equilibrium dynamics: relativistic GiBUU asymptotic equilibrated stage: statistical decay by means of SMM
Comparison with a wide selection of exp. data Comparison with a wide selection of exp. data Global characteristics and details fairly well reproduced
Future/under progress developmentsFuture/under progress developments Gradient terms in meson field equations (A.Larionov) Extended for iso-vector degrees of freedom (-meson) More consistent treatment of ground state (RTF)
DPG, 11.03.08
Ground state in BUU: Stability…Ground state in BUU: Stability…Ground state in BUU: Stability…Ground state in BUU: Stability…
Important in calculating EImportant in calculating Eexcexc
Energy must be conserved!
Important in calculating EImportant in calculating Eexcexc
Energy must be conserved!
Important in determing the Important in determing the sourcesource
No spurious particle emission!
Important in determing the Important in determing the sourcesource
No spurious particle emission!
Improved model for ground state simulations in BUU
B. Steimüller, O. Buss, U. Mosel, poster session, HK34.87
Improved model for ground state simulations in BUU
B. Steimüller, O. Buss, U. Mosel, poster session, HK34.87
DPG, 11.03.08
Dynamical aspects in Dynamical aspects in p+Xp+X reactions… reactions…Dynamical aspects in Dynamical aspects in p+Xp+X reactions… reactions…
Definition of residual nucleus: <sat/100.Definition of residual nucleus: <sat/100.
Combination: BUU+SMM (hybrid model)…Combination: BUU+SMM (hybrid model)…Combination: BUU+SMM (hybrid model)…Combination: BUU+SMM (hybrid model)…
Non-Equilibrium dynamics within BUU until system(s) approach local equilibrium at t=tf
Determination of A,Z and Eexc at time tf, and then apply SMM
Non-Equilibrium dynamics within BUU until system(s) approach local equilibrium at t=tf
Determination of A,Z and Eexc at time tf, and then apply SMM