Parameters of Sim08 Monte Carlo productions

Pythia6 Parameters

Pythia6 version 6.427 is used. The documentation of Pythia 6.4 can be found here.

Non default values of Pythia parameters are:

Parameter Value
ckin(41) 3.0
mstp(2) 2
mstp(33) 3
mstp(128) 2
mstp(81) 21
mstp(82) 3
mstp(52) 2
mstp(51) 10042 (ie CTEQ6 LO fit, with LOrder alpha_S PDF from LHAPDF)
mstp(142) 2
parp(67) 1.0
parp(82) 4.28
parp(89) 14000
parp(90) 0.238
parp(85) 0.33
parp(86) 0.66
parp(91) 1.0
parp(149) 0.02
parp(150) 0.085
parj(11) 0.4
parj(12) 0.4
parj(13) 0.769
parj(14) 0.09
parj(15) 0.018
parj(16) 0.0815
parj(17) 0.0815
mstj(26) 0
parj(33) 0.4

Minimum Bias Definition

The following Pythia processes are included in the minimum bias definition:

Process Number in Pythia Description
11 f + f' -> f + f' (QCD)
12 f + fbar -> f' + fbar'
13 f + fbar -> g + g
28 f + g -> f + g
53 g + g -> f + fbar
68 g + g -> g + g
91 Elastic scattering
92 Single diffractive (AB -> XB)
93 Single diffractive (AB -> AX)
94 Double diffractive
95 Low-pT scattering
421 g + g -> cc~[3S1(1)] + g
422 g + g -> cc~[3S1(8)] + g
423 g + g -> cc~[1S0(8)] + g
424 g + g -> cc~[3PJ(8)] + g
425 g + q -> q + cc~[3S1(8)]
426 g + q -> q + cc~[1S0(8)]
427 g + q -> q + cc~[3PJ(8)]
428 q + q~ -> g + cc~[3S1(8)]
429 q + q~ -> g + cc~[1S0(8)]
430 q + q~ -> g + cc~[3PJ(8)]
431 g + g -> cc~[3P0(1)] + g
432 g + g -> cc~[3P1(1)] + g
433 g + g -> cc~[3P2(1)] + g
434 q + g -> q + cc~[3P0(1)]
435 q + g -> q + cc~[3P1(1)]
436 q + g -> q + cc~[3P2(1)]
437 q + q~ -> g + cc~[3P0(1)]
438 q + q~ -> g + cc~[3P1(1)]
439 q + q~ -> g + cc~[3P2(1)]
461 g + g -> bb~[3S1(1)] + g
462 g + g -> bb~[3S1(8)] + g
463 g + g -> bb~[1S0(8)] + g
464 g + g -> bb~[3PJ(8)] + g
465 g + q -> q + bb~[3S1(8)]
466 g + q -> q + bb~[1S0(8)]
467 g + q -> q + bb~[3PJ(8)]
468 q + q~ -> g + bb~[3S1(8)]
469 q + q~ -> g + bb~[1S0(8)]
470 q + q~ -> g + bb~[3PJ(8)]
471 g + g -> bb~[3P0(1)] + g
472 g + g -> bb~[3P1(1)] + g
473 g + g -> bb~[3P2(1)] + g
474 q + g -> q + bb~[3P0(1)]
475 q + g -> q + bb~[3P1(1)]
476 q + g -> q + bb~[3P2(1)]
477 q + q~ -> g + bb~[3P0(1)]
478 q + q~ -> g + bb~[3P1(1)]
479 q + q~ -> g + bb~[3P2(1)]
480 g + g -> Psi(2S) + g
481 g + g -> Upsilon(2S) + g
482 g + g -> Upsilon(3S) + g
483 g + g -> Upsilon(4S) + g

Cross sections

Process Cross-sections in 4pi
  7 TeV, Pythia6 7 TeV, Pythia8 8 TeV, Pythia6 8 TeV, Pythia8
Total
Inclusive b/bbar
Inclusive c/cbar
Prompt Charmonium
Inclusive J/psi
Prompt J/psi
J/psi from B
Inclusive psi(2S)
Inclusive D0
D0 from B
Higgs
W
W + jets
Z
Z + jets
Drell-Yan (m>2 GeV)
Drell-Yan (m>10 GeV)

B Fractions

Hadron type Fractions in Monte Carlo
  7 TeV, Pythia6 7 TeV, Pythia8 8 TeV, Pythia6 8 TeV, Pythia8
B+, B-     41.0 +/- 0.6 %  
B0, B0bar     40.0 +/- 0.6 %  
Bs0, Bs0bar     10.1 +/- 0.4 %  
b Baryons     8.9 +/- 0.4 %  
D+, D-     20.7 +/- 0.1 %  
D0, D0bar     58.7 +/- 0.1 %  
Ds0, Ds0bar     11.4 +/- 0.1 %  
c Baryons     9.2 +/- 0.1 %  

Excited States Fractions

State Fractions in Monte Carlo
  7 TeV, Pythia6 7 TeV, Pythia8 8 TeV, Pythia6 8 TeV, Pythia8
B     21.2 +/- 0.1 %  
B*     63.0 +/- 0.1 %  
B**     15.8 +/- 0.1 %  
D     23.0 +/- 0.1 %  
D*     62.1 +/- 0.1 %  
D**     14.9 +/- 0.1 %  

Branching Fractions

The EvtGen main decay file contains all branching fractions used in the Monte Carlo generation.

Particle properties

The particles' properties (masses, widths and lifetimes) used in Sim08 generation are available in the DDDB at conddb:///param/ParticleTable.txt and can be quickly printed using the dump_particle_properties script.

B mixing

B0
  • τ(B0) = 1.519 x 10−12 s

B0s
  • τ(B0s_H) = 1.614 ps
  • τ(B0s_L) = 1.406 ps
  • τ(B0s) = 1.503 ps
  • ΔΓs = 0.0917 ps−1
  • τ(B0s → flavour specific) = (1/Γs) x [1 + (ΔΓs/2Γs)2] / [1 − (ΔΓs/2Γs)2] = 1.517 ps

-- AngeloDiCanto - 2014-11-05

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Topic revision: r5 - 2014-11-05 - AngeloDiCanto
 
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