JAANET::JLorentzBoost Struct Reference

Auxiliary class for performing Lorentz boosts. More...

#include <JLorentzBoost.hh>

Inheritance diagram for JAANET::JLorentzBoost:

Public Member Functions
	JLorentzBoost ()
	Default constructor. More...
	JLorentzBoost (const Boost &boost)
	Copy constructor. More...
double	getGamma () const
	Retrieve gamma factor. More...
template<class CoordSystem >
LorentzVector< CoordSystem >	operator() (const LorentzVector< CoordSystem > &x4) const
	Lorentz boost operator. More...
void	operator() (JVertex3D &vertex) const
	Lorentz boost operator. More...
void	operator() (JTrack3E &track, const double mass) const
	Lorentz boost operator. More...
void	operator() (Trk &track) const
	Lorentz boost operator. More...
void	operator() (Hit &hit) const
	Lorentz boost operator. More...
template<class T >
void	operator() (T __begin, T __end) const
	Lorentz boost operator. More...
void	operator() (Evt &event) const
	Lorentz boost operator. More...

Detailed Description

Auxiliary class for performing Lorentz boosts.

Definition at line 46 of file JLorentzBoost.hh.

Constructor & Destructor Documentation

JAANET::JLorentzBoost::JLorentzBoost ( )

inline

Default constructor.

Definition at line 52 of file JLorentzBoost.hh.

    {}

JAANET::JLorentzBoost::JLorentzBoost ( const Boost &  boost )

inline

Copy constructor.

Parameters

boost

Lorentz boost

Definition at line 61 of file JLorentzBoost.hh.

                                      :
      Boost(boost)
    {}

Member Function Documentation

double JAANET::JLorentzBoost::getGamma ( ) const

inline

Retrieve gamma factor.

Returns

gamma factor

Definition at line 71 of file JLorentzBoost.hh.

    {
      const double beta2 = this->BetaVector().Mag2();
      
      return 1.0 / sqrt(1.0 - beta2);
    }

template<class CoordSystem >

LorentzVector<CoordSystem> JAANET::JLorentzBoost::operator() ( const LorentzVector< CoordSystem > &  x4 ) const

inline

Lorentz boost operator.

Parameters

x4

4-vector

Returns

boosted 4-vector

Definition at line 86 of file JLorentzBoost.hh.

    {
      return static_cast<const Boost&>(*this)(x4);
    }

void JAANET::JLorentzBoost::operator() ( JVertex3D &  vertex ) const

inline

Lorentz boost operator.

Parameters

vertex

event vertex

Definition at line 97 of file JLorentzBoost.hh.

    {
      using namespace JPP;
      using namespace ROOT::Math;
      
      const XYZTVector x0(vertex.getX(), vertex.getY(), vertex.getZ(), vertex.getT() * getSpeedOfLight());
      const XYZTVector x1 = (*this)(x0);

      const JPosition3D pos1(x1.X(), x1.Y(), x1.Z());

      vertex.setPosition(pos1);
      vertex.setT(x1.T() / getSpeedOfLight());
    }

void JAANET::JLorentzBoost::operator() ( JTrack3E &  track, const double  mass  ) const

inline

Lorentz boost operator.

Parameters

track	track
mass	track particle mass

Definition at line 118 of file JLorentzBoost.hh.

    {
      using namespace JPP;
      using namespace ROOT::Math;
      
      const double Ekin = getKineticEnergy(track.getE(), mass);
      
      const XYZTVector x0(track.getX(), track.getY(), track.getZ(), track.getT() * getSpeedOfLight());
      const XYZTVector x1 = (*this)(x0);

      const PxPyPzEVector p0(Ekin * track.getDX(), Ekin * track.getDY(), Ekin * track.getDZ(), track.getE());
      const PxPyPzEVector p1 = (*this)(p0);

      const JVector3D pos1(x1.X(), x1.Y(), x1.Z());
      const JVersor3D dir1(p1.X(), p1.Y(), p1.Z());

      track.setPosition (pos1);
      track.setDirection(dir1);
      track.setT(x1.T());
      track.setE(p1.E());
    }

void JAANET::JLorentzBoost::operator() ( Trk &  track ) const

inline

Lorentz boost operator.

N.B.: Only initial and final state tracks are boosted.

Parameters

track

track

Definition at line 148 of file JLorentzBoost.hh.

    {
      using namespace std;
      using namespace JPP;
      using namespace ROOT::Math;

      // Boost momentum 4-vector

      if (is_finalstate(track) || is_initialstate(track)) {
      
        const Vec Ekin = (track.status != TRK_ST_ININUCLEI ?
                          getKineticEnergy(track) * track.dir : Vec(0.0, 0.0, 0.0));

        const PxPyPzEVector p0(Ekin.x, Ekin.y, Ekin.z, track.E);
        const PxPyPzEVector p1 = (*this)(p0);
      
        track.E   = p1.E();
        track.dir = Vec(p1.Px(), p1.Py(), p1.Pz());
        if (track.dir.len() > 0) { track.dir.normalize(); }

        // Boost track vertex and compute new track length,
        // assuming a relativistic particle traveling at the speed of light

        JVertex3D x0(getPosition(track.pos), track.t);         // Vertex 
        JVertex3D x1(getPosition(track.pos + track.len * track.dir),
                     track.t + track.len / getSpeedOfLight()); // Vertex + travel distance
      
        (*this)(x0); // Boost vertices
        (*this)(x1);

        track.t   = x0.getT() / getSpeedOfLight();
        track.pos = Vec(x0.getX(), x0.getY(), x0.getZ());

        track.len = x0.getDistance(x1);
      }
    }

void JAANET::JLorentzBoost::operator() ( Hit &  hit ) const

inline

Lorentz boost operator.

N.B.: The time-over-threshold is not boosted.

Parameters

hit

hit

Definition at line 192 of file JLorentzBoost.hh.

    {
      using namespace std;
      using namespace JPP;

      const double dt = hit.t - hit.tdc;
      
      JVertex3D vertex(getPosition(hit.pos), hit.t);
      (*this)(vertex);

      hit.pos = Vec(vertex.getX(), vertex.getY(), vertex.getZ());
      hit.t   = vertex.getT();

      hit.tdc = hit.t - getGamma() * dt;
    }

template<class T >

void JAANET::JLorentzBoost::operator() ( T  __begin, T  __end  ) const

inline

Lorentz boost operator.

Parameters

__begin	begin of data
__end	end of data

Definition at line 216 of file JLorentzBoost.hh.

    {
      using namespace std;
      
      for (T i = __begin; i != __end; ++i) {
        (*this)(*i);
      }
    }

void JAANET::JLorentzBoost::operator() ( Evt &  event ) const

inline

Lorentz boost operator.

N.B.: Intermediate state tracks as well as
the event timestamps and MC-time variable are not boosted.

Parameters

event

event

Definition at line 233 of file JLorentzBoost.hh.

    {
      (*this)(event.mc_trks.begin(), event.mc_trks.end());
      (*this)(event.mc_hits.begin(), event.mc_hits.end());
      (*this)(event.trks.begin(),    event.trks.end());
      (*this)(event.hits.begin(),    event.hits.end());      
    }

---

The documentation for this struct was generated from the following file:

• JLorentzBoost.hh