#include <BetaFuncPrimaryVertexGenerator.h>

Inheritance diagram for BetaFuncPrimaryVertexGenerator:

Public Member Functions
	BetaFuncPrimaryVertexGenerator (const edm::ParameterSet &vtx)
	Default constructor. More...

double	BetaFunction (double z, double z0)

virtual void	generate (RandomEngineAndDistribution const *)
	Generation process (to be implemented) More...

	~BetaFuncPrimaryVertexGenerator ()
	Destructor. More...

Public Member Functions inherited from PrimaryVertexGenerator
const math::XYZPoint &	beamSpot () const
	Return x0, y0, z0. More...

TMatrixD *	boost ()

const TMatrixD *	boost () const

	PrimaryVertexGenerator ()
	Default constructor. More...

virtual	~PrimaryVertexGenerator ()
	Destructor. More...

Private Member Functions
TMatrixD *	inverseLorentzBoost ()

Private Attributes
double	alpha_

double	fbetastar

double	femittance

double	fSigmaZ

double	fX0

double	fY0

double	fZ0

double	phi_

Additional Inherited Members
Protected Member Functions inherited from PrimaryVertexGenerator
void	setBoost (TMatrixD *)

Protected Attributes inherited from PrimaryVertexGenerator
math::XYZPoint	beamSpot_

TMatrixD *	boost_

Detailed Description

Definition at line 15 of file BetaFuncPrimaryVertexGenerator.h.

Constructor & Destructor Documentation

BetaFuncPrimaryVertexGenerator::BetaFuncPrimaryVertexGenerator ( const edm::ParameterSet & vtx )

Default constructor.

Definition at line 8 of file BetaFuncPrimaryVertexGenerator.cc.

References PrimaryVertexGenerator::beamSpot_, fX0, fY0, fZ0, inverseLorentzBoost(), and PrimaryVertexGenerator::setBoost().

                               :
   fX0(vtx.getParameter<double>("X0")),
   fY0(vtx.getParameter<double>("Y0")),
   fZ0(vtx.getParameter<double>("Z0")),
   fSigmaZ(vtx.getParameter<double>("SigmaZ")),
   alpha_(vtx.getParameter<double>("Alpha")),
   phi_(vtx.getParameter<double>("Phi")),
   fbetastar(vtx.getParameter<double>("BetaStar")),
   femittance(vtx.getParameter<double>("Emittance"))
 {
 
   this->setBoost(inverseLorentzBoost());
   beamSpot_ = math::XYZPoint(fX0,fY0,fZ0);
 
 } 

BetaFuncPrimaryVertexGenerator::~BetaFuncPrimaryVertexGenerator ( )

inline

Destructor.

Definition at line 23 of file BetaFuncPrimaryVertexGenerator.h.

23 {;}

Member Function Documentation

double BetaFuncPrimaryVertexGenerator::BetaFunction	(	double	z,
		double	z0
	)

set resolution in Z in cm set mean in X in cm beta function

Definition at line 43 of file BetaFuncPrimaryVertexGenerator.cc.

References fbetastar, femittance, and mathSSE::sqrt().

Referenced by generate().

 {
   return sqrt(femittance*(fbetastar+(((z-z0)*(z-z0))/fbetastar)));
 
 }

void BetaFuncPrimaryVertexGenerator::generate ( RandomEngineAndDistribution const * random )

virtual

Generation process (to be implemented)

Implements PrimaryVertexGenerator.

Definition at line 26 of file BetaFuncPrimaryVertexGenerator.cc.

References BetaFunction(), fSigmaZ, fX0, fY0, fZ0, and RandomEngineAndDistribution::gaussShoot().

                                                                                        {
 
   double tmp_sigz = random->gaussShoot(0., fSigmaZ);
   this->SetZ(tmp_sigz + fZ0);
 
   double tmp_sigx = BetaFunction(tmp_sigz,fZ0); 
   // need to divide by sqrt(2) for beamspot width relative to single beam width
   tmp_sigx *= 0.707107;
   this->SetX(random->gaussShoot(fX0,tmp_sigx));
 
   double tmp_sigy = BetaFunction(tmp_sigz,fZ0);
   // need to divide by sqrt(2) for beamspot width relative to single beam width
   tmp_sigy *= 0.707107;
   this->SetY(random->gaussShoot(fY0,tmp_sigy));
 
 }

TMatrixD * BetaFuncPrimaryVertexGenerator::inverseLorentzBoost ( )

private

Definition at line 51 of file BetaFuncPrimaryVertexGenerator.cc.

References alpha_, funct::cos(), phi_, and funct::sin().

Referenced by BetaFuncPrimaryVertexGenerator().

                                                     {
   
   TMatrixD* aBoost = 0;
   if ( fabs(alpha_) < 1E-12 && fabs(phi_) < 1E-12 ) return aBoost;
  
   TMatrixD tmpboost(4,4);
   
   // Lorentz boost to frame where the collision is head-on
   // phi is the half crossing angle in the plane ZS
   // alpha is the angle to the S axis from the X axis in the XY plane
 
   double calpha = std::cos(alpha_);
   double salpha = std::sin(alpha_);
   double cphi = std::cos(phi_);
   double sphi = std::sin(phi_);
   double tphi = sphi/cphi;
   tmpboost(0,0) = 1./cphi;
   tmpboost(0,1) = - calpha*sphi;
   tmpboost(0,2) = - tphi*sphi;
   tmpboost(0,3) = - salpha*sphi;
   tmpboost(1,0) = - calpha*tphi;
   tmpboost(1,1) = 1.;
   tmpboost(1,2) = calpha*tphi;
   tmpboost(1,3) = 0.;
   tmpboost(2,0) = 0.;
   tmpboost(2,1) = -calpha*sphi;
   tmpboost(2,2) = cphi;
   tmpboost(2,3) = - salpha*sphi;
   tmpboost(3,0) = - salpha*tphi;
   tmpboost(3,1) = 0.;
   tmpboost(3,2) = salpha*tphi;
   tmpboost(3,3) = 1.;
   
   tmpboost.Invert();
   aBoost = new TMatrixD(tmpboost);
 
   return aBoost;
 
 }