The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
Results from simulations of the production of secondary particles at
the pipe walls
M.Baznat1, K.K.Gudima1, E.I.Litvinenko2 , Yu.Murin2
1Institute of Applied Physics, Academy of Science of Moldova, Moldova2JINR Dubna, Russia
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
Outline
• Motivation of this study for CBM• LAQGSM generator• Rapidity• Transport of the spectators – nuclear fragments• Testing configurations of the beam pipe at the
STS region• Secondary particles and the pipe walls• Conclusion
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
LAQGSM high-energy event generator
LAQGSM describes reactions induced by both particles and nuclei at incident energies up to about 1 TeV/nucleon, generally, as a three-stage process: IntraNuclear Cascade (INC), followed by pre-equilibrium emission of particles during the equilibration of the excited residual nuclei formed after theINC, followed by evaporation of particles from and/or fission of the compound nuclei.
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
LAQGSM related publicaitons
• LAQGSM03.03: a) “CEM03.03 and LAQGSM03.03 Event Generators for the MCNP6, MCNPX, and MARS15 Transport Codes” S. G. Mashnik, K. K. Gudima, R. E. Prael, A. J. Sierk, M. I. Baznat, and N. V. Mokhov, LANL Report LA-UR-08-2931 ; E-print: arXiv:0805.0751v2 [nucl-th] 12 May 2008b) S. G. Mashnik et al., LANL Report LA-UR-07-6198; E-print: arXiv:0709.173v1 [nucl-th] 12 Sep 2007.c) K. K. Gudima and S. G. Mashnik, Proc. 11th Internat. Conf. on Nuclear Reaction Mechanisms, Varenna, Italy, June 12–16, 2006, edited by E. Gadioli (2006) pp. 525–534; E-print: nucl-th/0607007.
• LAQGSM03.01: S. G. Mashnik et al., LANL Report LA-UR-05-2686, Los Alamos (2005).
• LAQGSM: K. K. Gudima, S. G. Mashnik, A. J. Sierk, LANL Report LA-UR-01-6804, Los Alamos, 2001.
• Quark-Gluon String Model (QGSM): N. S. Amelin, K. K. Gudima, V. D. Toneev, Sov. J. Nucl. Phys. 51 (1990) 327–333; [Yad. Fiz. 51 (1990) 512–523]. Sov. J. Nucl. Phys. 51 (1990) 1093–1101; [Yad. Fiz. 51 (1990) 1730–1743]. Sov. J. Nucl. Phys. 52 (1990) 1722–178, [Yad. Fiz. 52 (1990) 272–282]
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
LAQGSM Au-Au sqrt(S)=5AGeV rapidity (5000 events)
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
Interface to LAQGSM data
Class constructor:
MpdLAQGSMGenerator (const char* fileName, const Bool_t use_collider_system=kTRUE);
---------------------------------
Class usage in simulation macro:
fRun->SetName("TGeant4");
MpdLAQGSMGenerator* guGen= new MpdLAQGSMGenerator(filename);
primGen->AddGenerator(guGen);
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
Geometry: Muon Magnet + 30 silicon planes:
0.3mm
0.004mm
Event generator: LAQGSMInput: a) “beam”, b) Au-Au, c) Au-p; Sqrt(S)=5 AGeVTransport: Geant4
The special testing configuration A:
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
A:Transport of “the beam” with this configuration
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
A: LAQGSM Au-Au sqrt(S)=5 AGeV 5000 events transported fragments
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
A: LAQGSM p-Au sqrt(S)=5 AGeV 5000 events transported fragments
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
A: Primary protons and fragments at z=50 and z=100 cm
Protons, z=50cm Protons, z=100cm Fragments, z=100cm
AuAu:
pAu:
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
Geometry: Muon Magnet + 8 silicon planes:
0.08mm
Event generator: LAQGSMPipe: conical tube from Be or Al (with wall 2mm, and in B case 1mm Be)STS: 8 plane silicon stations 0.08mm, 10cm around the pipe, standard positionsCollision: Au-Au Sqrt(S)=5 GeV/uTransport: Geant4
The special testing configurations B and C:
B: Be–1mm 1.6º, Al -2mm 2.9º inside pipe: vacuum
C: Be–2mm 2.5º, Al -2mm 2.5º, inside pipe: vacuum, or helium
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
B: Vertexes (r,z) of secondary particles, which came to STS planes(2200 LAQGSM events)
100% 114% [100%]
Be 1mm: Al 2mm:
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
B: Vertexes (r,z) of secondary electrons, which came to STS planes
(2200 LAQGSM events)
76% (100%) 80% [70%] (104%)
Be 1mm: Al 2mm:
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
B: Vertexes (r,z) of the secondary particles, which came to STS planes, that belong to the pipe wall
53% {100%} 70% [61%] {131%}
Be 1mm: Al 2mm:
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
C: Secondary particles born in the pipe wall (1000events)
2mm Be+vacuum:
2mm Al+vacuum:
2mm Be+helium:
2mm Al+helium:
100%
111%
100.5%
114%
B: Be 1mm - 78% ; Al 2mm – 102%
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
Maximal hit densities (per cm2 per event)
Allb allt allp z30 2.7 2.7 2.7 2.7
Allb allt allp z35 2.3 2.3 2.3 2.3
Allb allt allp z40 1.8 1.8 1.8 1.8
Allb allt allp z50 1.2 1.2 1.3 1.3
Allb allt allp z60 0.8 0.8 0.9 0.9
Allb allt allp z75 0.7 0.5 0.5 0.5
Allb allt allp z95 0.5 0.3 0.35 0.35
Allb allt allp z100 0.3 0.3 0.3 0.33
b<10 allt allp z30 2.4 2.4 2.4 2.4
b<10 allt allp z35 2.1 2.1 2.1 2.1
b<10 allt allp z40 1.6 1.6 1.6 1.6
b<10 allt allp z50 1.1 1.1 1.2 1.16
b<10 allt allp z60 0.7 0.8 0.8 0.8
b<10 allt allp z70 0.5 0.4 0.5 0.5
b<10 allt allp z95 0.3 0.3 0.3 0.3
b<10 allt allp z100
0.3 0.3 0.3 0.28
b<10 prim allp z30
2.2 2.2 2.2 2.2
b<10 prim allp z35
1.9 1.9 1.9 1.9
b<10 prim allp z40
1.4 1.4 1.4 1.4
b<10 prim allp z50
0.9 0.9 0.9 0.98
b<10 prim allp z60
0.6 0.6 0.6 0.6
b<10 prim allp z70
0.4 0.4 0.4 0.4
b<10 prim allp z95
0.27 0.27 0.26 0.27
b<10 prim allp z100
0.25 0.26 0.26 0.25
Be+vac Be+helAl+vac Al+hel
all
b<10
b<10prim
2.7 2.7
2.1 2.3
1.7 1.9
1.6 1.4
0.8 1.2
0.5 0.7
0.35 0.57
0.32 0.6
2.4 2.4
1.9 2.1
1.6 1.7
1.0 1.3
0.7 1.0
0.5 0.6
0.3 0.5
0.29 0.52
2.2 2.2
1.7 1.9
1.4 1.6
0.9 1.1
0.6 0.9
0.4 0.5
0.27 0.44
0.25 0.45
Al 2mm Be 1mmC: B:
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
C: Secondary particles – hit density per cm2 per event
Be+vac
Al+vac
z=30cm
z=30cm
z=50cm
z=50cm
Max=0.23
Max=0.18
z=100cm
Max=0.26
Max=0.2
Max=0.07
Max=0.07
Max=0.21
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
C: Secondary electrons – hit density per cm2 per event
Be+vac
Al+vac
z=30cm
z=30cm
z=50cm
z=50cm
Max=0.25 Max=0.18
Max=0.14Max=0.21
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
C: Secondary electrons for different b rangesBe+vac
Al+vac
z=30cmz=50cm z=100cm
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
B: Secondary electrons for different b ranges
Be+vac
Al+vac z=30cm z=50cm z=100cm
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
Conclusion
• The pipe walls made from aluminium and berillium are very similar in respect to the secondary particle production (only 10% difference, but Al is much cheaper).
• The pipe cone angle less than 2.5° has the following disadvantages: -- big part of the spectator particles, which should be measured to define the centrality of the event, can not be registered by PSD; -- these spectator particles create a lot of secondary particles when pass through the pipe walls and when pass through the STS parts made from silicon.
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
BACKUP SLIDES
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
LAQGSM intranuclear cascade model
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
The latest improvements of LAQGSM code
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
B: Vertexes (r,z) of secondary particles, which came to STS planes
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
B: All particles – hit distributions (arb.scale)
Be 1mm:
Al 2mm:
z=30cm
z=30cm
z=50cm
z=50cm
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
Magnetic field behaviour near x=0 z=100cm
The 3rd Work Meeting of the CBM-MPD STS Consortium, 1–4 June 2009, Sortavala, Karelia,
Russia
At large impact parameters the most of spectator nucleons are bound in fragments.
The NA49 collaboration. Eur. Phys. J., A2, 383, (1998)
Experimental data : the deposited energy for different types of spectators in dependence of
the centrality