Difference: HIMuons (9 vs. 10)

Revision 102010-09-15 - CameliaMironov

Line: 1 to 1
 
META TOPICPARENT name="Works"

Number of muons in HI generators

Line: 295 to 295
 
    • hydjet: nbcoll nucleon-nucleon on top of each other, in which ncoll_hard parton-parton scatterings take place

  • PYTHIA vs PYTHIA
Changed:
<
<
 
    • official (jets, diffractive,low_pT) vs hydjet_setting (jets, photons, MSTP(81)=0) -->
much more muons when no multiple interactions (initial,final) OFF
>
>
 
    • official (jets, diffractive,low_pT) vs hydjet_setting (jets, photons, MSTP(81)=0) -->
more muons when no multiple interactions (initial,final) OFF
 
 
    • official (jets, diffractive,low_pT) vs hydjet_setting (jets, photons but MSTP(81)=1) -->
slightly more than previous case (0.031 vs 0.028); so main diffrence from the channels
  • HYDJET vsPYTHIA scaled (only with jets and photons in)
    • hydro off, quenching on nhsel = 4 (kQJetsOnly)
    • hydro off, quenching off nhsel = 3 (kJetsOnly)
  • Added:
    >
    >
    • HYDJET and PYTHIA simple deal differently with the hard event generation when a pt_hat is applied
      • HYDJET recalculates the number of hard scattering
      • PYTHIA does NOT recalculate the number of hard scattering
    • What does this mean?
      • if NO pt_hat cut, (0 to infinity), there will be generated:
        • in HYDJET n_hydjet hard scatterings
        • in pythia, n_pythia hard scatterings
      • if YES pt_hat cut, there will be generated
        • in HYDJET, [n_hydjet - n_hydjet_(found in the pt<pt_hat interval)] (so only what is above the cut in the (1), a subset)
        • in PYTHIA, still all n_pythia hard scatterings
    • What is the effect?
      • You get more hard_scattering_probes in PYTHIA case than in HYDJET (just because you have more hard scatterings)
    • How to do comparison properly?
      • when comparing the 2 one has to make a x-section correction: Nbcol*N_PYTHIA(pt>ptcut)* [sigjet/sigin]
        • sigin is the total inelastic NN cross section at given cms energy (=58mb, it is actually input to HYDJET in the hydjet configuration file)
        • sigjet is the hard scattering NN cross section at given pt min and energy (=10.5474mb for pT_hat>6GeV, as taken from printout from hyjpar)
      • These 2 are stored as output from HYDJET in
        COMMON /hyjpar/ ptmin,sigin,sigjet,nhsel,ishad,njet 

     

    Results

     
    This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2019 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
    Ideas, requests, problems regarding TWiki? Send feedback