FCS Simulation Setup 2

Pythia setup for FCS simulation

Previous study on the forward pi0 cross-section found that Pythia ver. 6.4 + either tuneA or Perugia0 and <kT>=0.5GeV results in reasonable agreement with the published result.

Fig. 1. Forward pi0 cross-section in Pythia 6.4 tuneA vs. Perugia0, <kT>=0.5 and 1.0GeV

Fig. 2. Perguia0 vs. published FPD results

Based on this, we are considering the following Pythia setup for the full FCS simulation. 

Version: 6.4
Tune: TuneA 
Gaussian width of primordial <kT> = 0.5 GeV  

Limits on p_perp (transverse momentum of 2->2 hard process)
    ckin3=0.0 GeV (might be too low)
    ckin4=-1.0 (no upper limit)

Additional limit for processes that diverges as p_perp -> 0
    ckin56=1.0 GeV

Included proesses 
    Pythia.SetMSUB(11,1);  //qq->qq
    Pythia.SetMSUB(12,1);  //qqbar->qqbar
    Pythia.SetMSUB(13,1);  //qqbar->gg
    Pythia.SetMSUB(28,1);  //qg->qg
    Pythia.SetMSUB(53,1);  //gg->qqbar
    Pythia.SetMSUB(68,1);  //gg->gg
    //heavy flavour
    Pythia.SetMSUB(81,1);  //qqbar->QQbar
    Pythia.SetMSUB(82,1);  //gg->QQbar
    Pythia.SetMSUB(86,1);  //gg->J/psi+g
    Pythia.SetMSUB(87,1);  //gg->chi0c+g
    Pythia.SetMSUB(88,1);  //gg->chi1c+g
    Pythia.SetMSUB(89,1);  //gg->chi2c+g
    Pythia.SetMSUB(106,1);  //gg -> J/Psi+p
    Pythia.SetMSUB(94,1);  //double diff
    Pythia.SetMSUB(95,1);  //low pt
    //direct photon
    Pythia.SetMSUB(14,1);  //qqbar->gp
    Pythia.SetMSUB(18,1);  //qqbar->pp
    Pythia.SetMSUB(29,1);  //qg->qp
    Pythia.SetMSUB(114,1); //gg->pp
    Pythia.SetMSUB(115,1); //gg->gp