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Needs: 1. Centrality control; 2. Radiation load; 3. Cosmic ray studies

Coupling of UrQMD Model with Statistical Multi- Fragmentation Model A.Galoyan, V.Uzhinsky VBLHEP and LIT JINR. Aim - understanding/description of nuclear fragmentation at high energies. Needs: 1. Centrality control; 2. Radiation load; 3. Cosmic ray studies. Contents. Theoretical models:

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Needs: 1. Centrality control; 2. Radiation load; 3. Cosmic ray studies

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  1. Coupling of UrQMD Model with Statistical Multi- Fragmentation ModelA.Galoyan, V.UzhinskyVBLHEP and LIT JINR Aim - understanding/description of nuclear fragmentation at high energies Needs: 1. Centrality control; 2. Radiation load; 3. Cosmic ray studies Contents • Theoretical models: • AA, QMD, Glauber+RTIM • UrQMD and SMM • Calculation results • Conclusion

  2. J. Hufner, K. Schafer, B. Schurmann Phys.Rev.C12:1888-1898,1975 Abrasion-ablation in reactions between relativistic heavy ions. L.F. Oliveira, R. Donangelo, J. O. Rasmussen Phys.Rev.C19:826-33,1979. Abrasion-ablation calculations of large fragment yields from relativistic heavy ion reactions. J.J. Gaimard, K.H. Schmidt Nucl.Phys.A531:709-746,1991. A Reexamination of the abrasion - ablation model for the description of the nuclear fragmentation reaction. Models: Abrasion-ablation The expression for the cross section for abrasion of n nucleons: The excitation energy:

  3. A. Pshenichnov, J. P. Bondorf, I. N. Mishustin, A. Ventura, S. Masetti Phys. Rev. C64, 024903, 2001 Mutual heavy ion dissociation in peripheral collisions at ultrarelativistic energies Models: Abrasion-ablation – RELDIS code The model is a combination of the electromagnetic dissociation, the abrasion-ablation model, the Statictical Multi-Fragmentation model

  4. C. Scheidenberger et al. Phys. Rev. C70, 014902, 2004 Charge-changing interactions of ultrarelativistic Pb nuclei Models: Abrasion-ablation – RELDIS code

  5. Models: Quantum Molecular Dynamics Model J.Aichelin, Phys. Rep. 202 (1991) 233; D.H.Boal and J.N.Glosli, Phys. Rev. C38 (1988) 1870; 2621 K.Niita, S.Chiba et al., Phys. Rev. C52 (1995) 2620; Ch.Hartnack, Rajeev K. Puri, J.Aichelin, J.Konopka, S.A.Bass, H.Stoker and W.Greiner, Eur. Phys. J. A1 (1998) 151. In the QMD model each nucleon (or quasi-particle) is assumed to be aconstant width minimal wave packet (coherent state). V(ri-rj) ?

  6. Models: Quantum Molecular Dynamics Model The N-body ''wavefunction'', ψN, describing the entirenucleus is taken to be a direct product of single particle statesψi. Here r0iandp0i are the mean position andmomentum of the nucleoni and the width of the wave packet is characterized byparameterL.

  7. Models: Quantum Molecular Dynamics Model

  8. Models: Quantum Molecular Dynamics Model

  9. Models: Quantum Molecular Dynamics Model The total energyarising from the "Pauli interaction“: where the Kronecker deltas ensure that the potential acts between quasi-particles only. The Coulomb potential for Gaussian charge distribution can be expressed interms of the erf functions:

  10. Models: Quantum Molecular Dynamics Model Stohastic interactions Clusterization Rij< Rc~ 2-4 fm

  11. ANALYSIS OF THE (N, X N-PRIME) REACTIONS BY QUANTUM MOLECULAR DYNAMICS PLUS STATISTICAL DECAY MODEL.K. Niita, S. Chiba, Toshiki Maruyama, Tomoyuki Maruyama, H. Takada, T. Fukahori, Y. Nakahara, A. Iwamoto (JAERI, Tokai),. • Phys.Rev.C52:2620-2635,1995 Neutron energy spectra for the reaction p(1500 MeV)+Pb. The solid histograms are the results of QMD+SDM, and points are experimental data.

  12. Models: Glauber + RTIM+SMM = New FRITIOF K. Abdel-Waged, V. Uzhinsky Yad.Fiz.60:925-937,1997. Model of nuclear disintegration in high-energy nucleus nucleus interactions Glauber approximation underestimates nuclear destrustion! We have considered enhansed Diagram contributions

  13. Models: Glauber + RTIM+SMM = New FRITIOF K. Abdel-Waged, V. Uzhinsky Phys.Atom.Nucl.60:828-840,1997, Yad.Fiz.60:925-937,1997. Model of nuclear disintegration in high-energy nucleus nucleus interactions Si+Al, Cu, Pb, 14.8 GeV/c/nucleon RTIM CEM (DCM)

  14. Models: Glauber + RTIM+SMM = New FRITIOF K. Abdel-Waged, V. Uzhinsky Phys.Atom.Nucl.60:828-840,1997, Yad.Fiz.60:925-937,1997. Model of nuclear disintegration in high-energy nucleus nucleus interactions O+A, 60 GeV/N

  15. Models: Glauber + RTIM+SMM = New FRITIOF K. Abdel-Waged, V. Uzhinsky Phys.Atom.Nucl.60:828-840,1997, Yad.Fiz.60:925-937,1997. M.I.Adamovich et al. (EMU-01 collab.) Zeit. Fur Phys. A359,277, 1997 Multifragmentation of gold nuclei in the interactions with photoemulsion nuclei at 10.7-GeV/nucleon.

  16. UrQMD Model

  17. Initialization UrQMD Model In configuration space the centroids of the Gaussians are randomly distributed within a sphere with R=r0(0.5*[A+(A1/3-1)3])1/3 (fm) The initial momenta of the nucleons are randomly chosen between 0 and local Thomas-Fermi momentum The initialized nuclei are not in their ground state, and can evaporate single nucleons after 20-30 fm/c. Pauli potential is not included. It can be included optionally. Potentials Skyrme-type, Yukawa, Coulomb and Pauli ones Collisions Cross sections are very good! Pauli blocking included Clusterization does not considered Evaporation does not considered

  18. UrQMD Model Patches to UrQMD Model Code A. Galoyan, J. Ritman, V. Uzhinsky e-Print: nucl-th/0605021 Patches to UrQMD Model Code. Changes in the file URQMD.F c optional decay of all unstable particles before final output c DANGER: pauli-blocked decays are not performed !!! if(CTOption(18).eq.0) then c no do-loop is used because npart changes in loop-structure i=0 nct=0 actcol=0 c disable Pauli-Blocker for final decays old_CTOption10=CTOption(10) ! Aida CTOption(10)=1 c decay loop structure starts here 40 continue i=i+1 c is particle unstable if(dectime(i).lt.1.d30) then 41 continue isstable = .false. do 44 stidx=1,nstable if (ityp(i).eq.stabvec(stidx)) then c write (6,*) 'no decay of particle ',ityp(i) isstable = .true. endif 44 enddo if (.not.isstable) then c perform decay call scatter(i,0,0.d0,fmass(i),xdummy) c backtracing if decay-product is unstable itself if(dectime(i).lt.1.d30) goto 41 endif endif c check next particle if(i.lt.npart) goto 40 endif ! final decay CTOption(10)=old_CTOption10 ! Return to the old value ! c final output Changes in the file STRING.F ! call getmas(m0,w0,mindel,isoit(mindel),mmin,mmax,-1.,amass) !Aida call getmas(m0,w0,mindel,isoit(mindel),mmin,mmax,-1.d0,amass)!Aida ! ^^

  19. UrQMD Model Patches to UrQMD Model Code Changes in the file PROPPOT.F REAL*8 ERF (in Proppot.f) REAL*4 ERF (Erf.f) Original line : Cb = Cb0/rjk(j,k)*erf(sgw*rjk(j,k)) was replaced by: Cb = Cb0/rjk(j,k)*erf(sngl(sgw*rjk(j,k))) ! Aida ! ^^^^^ ^ Original lines : dCb = Cb0*(er0*exp(-(gw*rjk(j,k)*rjk(j,k)))*sgw*rjk(j,k)- + erf(sgw*rjk(j,k)))/rjk(j,k)/rjk(j,k) were replaced by: dCb = Cb0*(er0*exp(-(gw*rjk(j,k)*rjk(j,k)))*sgw*rjk(j,k)- + erf(sngl(sgw*rjk(j,k))))/rjk(j,k)/rjk(j,k) ! Aida ^^^^^ ^ Changes in the file INIT.F Parameter (nnucl=1) ! 10) ! Aida For debugging purposes

  20. UrQMD Model Patches to UrQMD Model Code Changes in the file ANNDEC.F In file "tabinit.f", in "subroutine mkwtab", it is checked that the probability of decay channel of a resonance is not zero ("bran.gt.1d-9"). If it is zero, the spline coefficients are not determined. At the same time, in the file anndec.f, in subroutine anndex, it is not checked that the probability is zero. Due to this the code go out of the allowed region. To improve the situation we have added many lines in the subroutine anndex. C one ingoing particle --> two,three,four outgoing particles C c... decays do 3 i=0,maxbr if((minbar.le.iabs(i1)).and.(iabs(i1).le.maxbar)) then ! Uzhi call b3type (i1,i,bran_uz,i1_uz,i2_uz,i3_uz,i4_uz) ! Uzhi if(bran_uz.le.1.d-9) then ! Uzhi see mkwtab prob(i)=0.d0 ! Uzhi else ! Uzhi if(isoit(btype(1,i))+isoit(btype(2,i))+isoit(btype(3,i))+ ! Uzhi & isoit(btype(4,i)).lt.iabs(iz1).or. ! Uzhi & m1.lt.mminit(btype(1,i))+mminit(btype(2,i)) ! Uzhi & +mminit(btype(3,i))+mminit(btype(4,i)) )then ! Uzhi prob(i)=0.d0 ! Uzhi

  21. UrQMD Model Patches to UrQMD Model Code Changes in the file ANNDEC.F else ! Uzhi prob(i)=fbrancx(i,iabs(i1),iz1,m1,branch(i,iabs(i1)), ! Uzhi & btype(1,i),btype(2,i),btype(3,i),btype(4,i)) ! Uzhi endif ! Uzhi endif ! Uzhi else ! For mesons ! Uzhi if(isoit(btype(1,i))+isoit(btype(2,i))+isoit(btype(3,i))+ & isoit(btype(4,i)).lt.iabs(iz1).or. & m1.lt.mminit(btype(1,i))+mminit(btype(2,i)) & +mminit(btype(3,i))+mminit(btype(4,i)) )then prob(i)=0.d0 else prob(i)=fbrancx(i,iabs(i1),iz1,m1,branch(i,iabs(i1)), & btype(1,i),btype(2,i),btype(3,i),btype(4,i)) endif endif ! Uzhi 3 continue Due to all of these changes the code works quite fast and stable! Simulation of 10000 events of Au+Au interactions at 25 GeV/c/nucleon took only 10 hours in cascade mode.

  22. UrQMD Model: Input-Output Changes Input.f CTOption(5) = 0 -> 1 (random b from bmin to bmax bdb weighted) CTOption(21) = 0 -> 1 (Lund Fragmentation Function) CTOption(27) = 0 -> 1 (target lab frame) Tottime = 100 fm/c (total time to calculate for event) Outtime = 100 fm/c (time interval for output) Random number generator is changed Fortran operators - open file, read, write are closed Output.f ( output to file13, 14, 15, 16, 17, 20 is closed) i_f=i_f+1 !aida id_f(i_f)=id !aida charge_f(i_f)=charge(i) !aida px_f(i_f) = px(i)+ffermpx(i) !aida py_f(i_f) = py(i)+ffermpy(i) !aida pz_f(i_f) = pz(i)+ffermpz(i) !aida p0_f(i_f) = p0(i) !aida fmass_f(i_f)= fmass(i) !aida Current random number - ranseed Output to file 19: ROOT TTree : “data”

  23. Statistical Multi-Fragmentation Model - SMM J.P. Bondorf, A.S. Botvina, A.S. Ilinov, I.N. Mishustin, K. Sneppen Phys.Rept.257:133-221,1995.Statistical multifragmentation of nuclei.

  24. Statistical Multi-Fragmentation Model - SMM Old SMM New SMM by A.S. Botvina

  25. Statistical Multi-Fragmentation Model - SMM Program implementation Root TTree Baryons Mesons Fragments, baryons Potential calculations Eos = 1 UrQMD Excitation energy SMM Fragments?

  26. Calculations: p+A

  27. Calculations: p+A

  28. Calculations: p+A

  29. Calculations: p+A Exp. Data - PS208 Collab.,LEAR SMM or Evaporation With and without SMM

  30. Isotope production in p+16O

  31. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, JINR, Prop. chamber Charged particles multiplicities. Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  32. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, Pion multiplicities as functions of Q – involved protons π--mesonsπ+ -mesons Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  33. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, Proton multiplicities versus Q Proton-participantEvaporated protons Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  34. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, Multiplicities of spectator protons Multiplicities of multi-charged fragments Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  35. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, Average pion momenta as functions of Q π- -mesons π+ -mesons Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  36. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, Average pion momenta as functions of Q π- -mesons π+ -mesons Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  37. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, Average participant proton momenta versus Q Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  38. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, π– meson rapidity distributions in CC-interactions Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  39. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, Rapidity distributions of participant protons in CC interactions Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  40. Calculations: p, d, He-4, C-12 + C, 4.2 GeV/c/N, Laboratory momentum distributions of participant protons in CC-interactions Points – Exp. Data. Red – UrQMD+SMM, green – Fritiof+SMM, blue – Cascade.

  41. Calculations: Au+Au

  42. Calculations: Au+Au ZDC must be tuned!

  43. Problems Too strong destruction!!!

  44. Conclusion • Clusterization and evaporation/fragmentation are implemented into the UrQMD program versions 1.3 and 2.3. • It is checked that results have a weak dependence on evaporation/fragmentation model. • Neutron energy spectra for pA interactions are calculated. Good results are obtained. • The model underestimates yield of neutrons with energy less than 10 MeV. • Good results are obtained for AC-interactions. • Some calculations are done for Au+Au interactions. • Tuning and checking of the combination is needed!

  45. Conclusion • New version of Statistical Multi-fragmentaion Model has been coupled with UrQMD model to further use in CBM and PANDA software. Additional testing of the UrQMD + SMM is needed. • Some drawbacks were located in UrQMD 1.3 and 2.3. Problems: • Calculations using UrQMD+SMM model require too many computer time. Operation of Cascade, New Fritiof and UrQMD 1.3 codes can be checked at WEB-portal – HEPWEB.JINR.RU (LIT JINR)

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