# Introduction

This lists the filters recommended for use in the HLT and the selections. See DaVinciTutorial4 for a hnads-on tutorial. A longer, but not necessaraly up-to-date list can be found at LoKiParticleFunctions.

# Particle Functors

## ALL: All

Takes all particles. This is required if one wants to apply no cut.
CombineParticles.FILTER0.Code = "(ALL)" ;

## ABSID:

CombineParticles.FILTER2.Code = "" ;

## ADMASS:

CombineParticles.FILTER2.Code = "" ;

## BPVDIRA: Direction angle

Computes the cosine of the angle between the momentum of the particle and the direction fo flight from the best PV to the decay vertex.
CombineParticles.FILTER2.Code = "(BPVDIRA>0.9999)" ;

## BPVIPCHI2(): IP on related PV

Computes the -IP on the related PV.
CombineParticles.FILTER2.Code = "BPVIPCHI2()<25" ;
So far it needs the ().

## BPVVDCHI2: -separation from related PV

Computes the -distance from the related PV.
CombineParticles.FILTER2.Code = "(BPVVDCHI2>100)" ;

## CHILDCUT:

CombineParticles.FILTER2.Code = "" ;

## ID:

CombineParticles.FILTER2.Code = "" ;

## INTREE: In tree

Requires there is a particle in the decay tree satisfying the requirements.
FilterDesktop.Filter.Code = "(INTREE( (ID=='J/psi(1S)') & (BPVVDCHI2>25) ) )" ;
Requires there is a in the tree more than 5\sigma away from the best vertex.

## MAXTREE:

CombineParticles.FILTER2.Code = "" ;

## MINTREE: Minimal value in the decay tree

Takes a functor as agrument and returns its minimal value searching through the decay tree.
CombineParticles.FILTER0.Code = "(MINTREE(ABSID=='K+',PT)>1400)" ;
This would look for all particles kaons in the decay tree and find their and return the minimum. The cut then requires that all kaon descendents ahve a .

## MIPCHI2DV:

CombineParticles.FILTER2.Code = "" ;

## MIPDV:

CombineParticles.FILTER2.Code = "" ;

## M:

CombineParticles.FILTER2.Code = "" ;

## MM:

CombineParticles.FILTER2.Code = "" ;

## NINTREE: Number of particles in tree

Returns the number of particles in a tree satisfying some selection criteria.
CombineParticles.FILTER0.Code = "( 2 == NINTREE( (ABSID=='e-') & (PT>1000)))" ;
Reuqires that there are two electrons in the tree with .

## P:

CombineParticles.FILTER2.Code = "" ;

## PIDe, ==, :

CombineParticles.FILTER2.Code = "" ;

## PT:

CombineParticles.FILTER2.Code = "" ;

## TRCHI2DOF:

CombineParticles.FILTER2.Code = "" ;

## VDMIN:

CombineParticles.FILTER2.Code = "" ;

## VFASPF: Vertex Function as Particle Function.

Allows to apply vertex functors to the particle's endVertex().
CombineParticles.FILTER2.Code = "(VFASPF(VCHI2/VDOF)<10)" ;
Applies a cut to the vertex of the particle.

# Vertex functors

Vertex functors are accessed using VFASPF.

## VCHI2

CombineParticles.FILTER2.Code = "" ;

## VDOF

CombineParticles.FILTER2.Code = "" ;

-- PatrickKoppenburg - 27 Mar 2008

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Topic revision: r1 - 2008-03-27 - unknown

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