Changes between Version 1 and Version 2 of MadOniaDescription


Ignore:
Timestamp:
04/06/12 16:33:03 (7 years ago)
Author:
trac
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • MadOniaDescription

    v1 v2  
    44== Short description of the tool ==
    55
    6 The aim is to build an event generator for quarkonium physics. Production rates are computed within the NRQCD theory (Non-Relativistic QCD, Bodwin, Braaten and Lepage, see hep-ph/9407339), where cross sections are expanded in %$\alpha_s$% and %$\normalsize v$%, the relative velocity in the heavy quarkonium state. As a result, cross sections read
     6The aim is to build an event generator for quarkonium physics. Production rates are computed within the NRQCD theory (Non-Relativistic QCD, Bodwin, Braaten and Lepage, see hep-ph/9407339), where cross sections are expanded in $\alpha_s$ and $\normalsize v$, the relative velocity in the heavy quarkonium state. As a result, cross sections read
    77
    88
    99
    10 where  the creation of a heavy-quark pair is described by the short-distance coefficients %$\hat \sigma(Q\bar Q(n))$%, whereas the non-perturbative evolution of this heavy-quark pair into a quarkonium state is encoded into the long-distance matrix elements  %$<O^{\mathcal Q}(n)>$%. The label %$\normalsize n $% stands for the intermediate state of the heavy quark pair, which is usually expressed in the spectroscopic notation:
     10where  the creation of a heavy-quark pair is described by the short-distance coefficients $\hat \sigma(Q\bar Q(n))$, whereas the non-perturbative evolution of this heavy-quark pair into a quarkonium state is encoded into the long-distance matrix elements  $<O^{\mathcal Q}(n)>$. The label $\normalsize n $ stands for the intermediate state of the heavy quark pair, which is usually expressed in the spectroscopic notation:
    1111
    1212
    1313
    14 with %$\normalsize S $% the spin of the heavy quark pair, %$ \normalsize L $% its orbital angular momentum, %$ \normalsize J $% its total angular momentum, and %$ \normalsize c $% its color state.
     14with $\normalsize S $ the spin of the heavy quark pair, $ \normalsize L $ its orbital angular momentum, $ \normalsize J $ its total angular momentum, and $ \normalsize c $ its color state.
    1515 
    16 MadOnia automatically generates any tree-level amplitude for an arbitrary transition %$\normalsize n$% (up to P-wave state) required for the computation of the short-distance coefficients. The amplitude generator is interfaced with MadEvent to produce unweighted events. These events are written in the same format in the  lhe format and can be passed through Pythia for the showering and hadronization.
     16MadOnia automatically generates any tree-level amplitude for an arbitrary transition $\normalsize n$ (up to P-wave state) required for the computation of the short-distance coefficients. The amplitude generator is interfaced with MadEvent to produce unweighted events. These events are written in the same format in the  lhe format and can be passed through Pythia for the showering and hadronization.
    1717
    1818
     
    3333
    3434
     35