PYTHIA  8.303
Public Member Functions | List of all members
Resolution Class Reference

A simple class for containing evolution variable definitions. More...

#include <VinciaCommon.h>

Public Member Functions

 Resolution ()=default
 Constructor.
 
virtual ~Resolution ()
 Destructor.
 
void initPtr (Settings *settingsPtrIn)
 Initialize pointers (must be done before init).
 
bool init ()
 Initialize. More...
 
double q2sector2to3 (const Particle *a, const Particle *b, const Particle *j, bool=false)
 Sector resolution functions. More...
 
double q2sector3to4 (const Particle *, const Particle *, const Particle *j1, const Particle *j2)
 
double q2sector2to4 (const Particle *a, const Particle *b, const Particle *j1, const Particle *j2)
 
double q2sector3to5 (Particle *a, Particle *b, Particle *j1, Particle *j2, Particle *j3)
 
double findSector (vector< int > &iSec, vector< Particle > state, int nFmin=1)
 
void setVerbose (int verboseIn)
 Set verbosity level.
 

Detailed Description

A simple class for containing evolution variable definitions.

Member Function Documentation

double findSector ( vector< int > &  iSec,
vector< Particle state,
int  nFmin = 1 
)

Sector accept function. Optionally prevent g->qq clusterings if that would reduce the number of fermion lines below some minimum (cheap way to indicate that Z->qq/ll always has at least one fermion pair).

Initialise.

Do all possible 2->3 clusterings. Note, needs modification for 3->4 and 2->4 showers.

There are no sectors for emission into the initial state.

If a gluon, compute LC pT from colour partners.

If fermion, check if we are allowed to look at this clustering.

Skip if this clustering would reduce below number requested.

Cluster quark: recoiler is the anticolour partner. Cluster antiquark: recoiler is colour partner.

Loop over all same-flavour (anti)quarks (must in principle also require opposite helicities).

Other sectors (QED, EW, ...) to be implemented here.

End loop over ir.

Return smallest scale found.

bool init ( )

Initialize.

The Resolution class.

Initialize.

Check that pointers initialized.

Set members.

double q2sector2to3 ( const Particle a,
const Particle b,
const Particle j,
bool  = false 
)

Sector resolution functions.

Construct basic 4-products.

Gluon emission.

FF emission.

IF emission.

IF emission (a <-> b).

II emission.

FF Gluon splitting.

Assume b is recoiler.

Find colour-connected invariant.

Normalisation.

Return the g->qq sector variable defined in arXiv:1109.3608.

double q2sector2to4 ( const Particle a,
const Particle b,
const Particle j1,
const Particle j2 
)

Sector resolution function for 2->4 branchings (double emission). Assume j1 and j2 are colour connected, with a and b hard recoilers.

double q2sector3to4 ( const Particle ,
const Particle ,
const Particle j1,
const Particle j2 
)

Sector resolution function for 3->4 branchings (currently only used for gluon splitting, with m2qq as the measure).

double q2sector3to5 ( Particle a,
Particle b,
Particle j1,
Particle j2,
Particle j3 
)

Sector resolution function for 3->5 branchings (emission + splitting).

j3 is gluon.


The documentation for this class was generated from the following files: