#include <SigmaTotal.h>

Inheritance diagram for SigmaABMST:

Public Member Functions
	SigmaABMST ()
	Constructor.

virtual void	init (Info *infoPtrIn)
	Initialize data members. More...

virtual bool	calcTotEl (int idAin, int idBin, double sIn, double, double)
	Calculate integrated total/elastic cross sections. More...

virtual double	dsigmaEl (double t, bool useCoulomb=false, bool onlyPomerons=false)
	Differential elastic cross section.

virtual bool	calcDiff (int idAin, int idBin, double sIn, double, double)
	Calculate integrated diffractive cross sections. More...

virtual double	dsigmaSD (double xi, double t, bool=true, int=0)
	Differential single diffractive cross section. More...

virtual double	dsigmaDD (double xi1, double xi2, double t, int=0)
	Differential double diffractive cross section. More...

virtual double	dsigmaCD (double xi1, double xi2, double t1, double t2, int=0)
	Differential central diffractive cross section. More...

virtual double	mMinCD ()
	Minimal central diffractive mass.

Public Member Functions inherited from SigmaTotAux
	SigmaTotAux ()
	Constructor.

virtual	~SigmaTotAux ()
	Destructor.

virtual bool	calcTot (int, int, double)
	Calculate total cros section only. Only implemented for SigmaSaSDL.

virtual bool	splitDiff ()
	Possibility to separate xi and t choices for diffraction.

pair< double, double >	tRange (double sIn, double s1In, double s2In, double s3In, double s4In)

bool	tInRange (double tIn, double sIn, double s1In, double s2In, double s3In, double s4In)

double	pFormFac (double tIn)
	Commonly used proton form factor.

Additional Inherited Members
Public Attributes inherited from SigmaTotAux
bool	isExpEl
	Store total and elastic cross section properties.

bool	hasCou

double	sigTot

double	rhoOwn

double	sigEl

double	bEl

double	sigTotCou

double	sigElCou

double	sigXB
	Store diffractive cross sections. Possibly also sigmaND.

double	sigAX

double	sigXX

double	sigAXB

double	sigNDtmp

Protected Member Functions inherited from SigmaTotAux
virtual bool	initCoulomb (Settings &settings, ParticleData *particleDataPtrIn)
	Initialize Coulomb correction parameters. More...

virtual bool	addCoulomb ()
	Add Coulomb corrections to the elastic and total cross sections. More...

virtual double	dsigmaElCoulomb (double t)
	Coulomb contribution to the differential elastic cross sections. More...

Protected Attributes inherited from SigmaTotAux
int	idA
	Initialization data, normally only set once.

int	idB

bool	tryCoulomb
	Add Coulomb corrections to the elastic cross section.

double	chgSgn

double	tAbsMin

double	lambda

double	phaseCst

ParticleData *	particleDataPtr
	Pointer to the particle data table.

Rndm *	rndmPtr
	Pointer to the random number generator.

Static Protected Attributes inherited from SigmaTotAux
static const int	NPOINTS = 1000
	Constants: could only be changed in the code itself. More...

static const double	ALPHAEM = 0.00729353
	alpha_em(0). More...

static const double	CONVERTEL = 0.0510925
	Conversion coefficients = 1/(16pi) * (mb <-> GeV^2).

static const double	MPROTON = 0.9382720
	Proton and pion masses, and their squares. Euler's constant.

static const double	SPROTON = 0.8803544

static const double	MPION = 0.1349766

static const double	SPION = 0.0182187

static const double	GAMMAEUL = 0.577215665

static const double	TABSREF = 2e-3
	Reference scale for nominal definition of t slope.

static const double	TABSMAX = 1.

static const double	MINSLOPEEL = 10.

Detailed Description

The SigmaABMST class parametrizes total and elastic cross sections according to Appleby, Barlow, Molson, Serluca and Toader (ABMST).

Member Function Documentation

bool calcDiff	(	int	idAin,
		int	idBin,
		double	sIn,
		double	,
		double
	)

virtual

Calculate integrated diffractive cross sections.

Diffractive cross sections.

Find appropriate combination of incoming beams.

Total cross section needed for central diffraction.

Single diffractive cross sections by grid integration.

Double diffractive cross section by Monte Carlo or grid integration.

Central diffractive cross section by Monte Carlo integration.

Done.

Reimplemented from SigmaTotAux.

bool calcTotEl	(	int	idAin,
		int	idBin,
		double	sIn,
		double	,
		double
	)

virtual

Calculate integrated total/elastic cross sections.

Calculate total and (integrated) elastic cross sections.

Find appropriate combination of incoming beams.

Total cross section and the rho parameter using the full expression.

Total elastic cross section, by integration in exp( MINSLOPEEL * t).

Approximate exponential slope.

Done if no Coulomb corrections.

Reduce hadronic part of elastic cross section by tMin cut.

Loop through t range according to dt/t^2.

Evaluate cross section difference between with and without Coulomb.

Include common factors to give new elastic and total cross sections.

Done.

Reimplemented from SigmaTotAux.

double dsigmaCD	(	double	xi1,
		double	xi2,
		double	t1,
		double	t2,
		int	= `0`
	)

virtual

Differential central diffractive cross section.

ABMST valid for |t| < 4.

dSigma_CD(x1, x2, t1, t2) = dSigma_SD(x1, t1) * dSigma_SD(x2, t2) / sigma_tot.

Minimal fall-off relative to t = 0 value.

Optionally dampen with 1 / (1 + exp( -p * (y - y_gap))) for both gaps.

Optionally multiply by s-dependent factor.

Done.

Reimplemented from SigmaTotAux.

double dsigmaDD	(	double	xi1,
		double	xi2,
		double	t,
		int	= `0`
	)

virtual

Differential double diffractive cross section.

Calculate mass and check it is above threshold. ABMST valid for |t| < 4.

dSigma_DD(x1, x2, t) = dSigma_SD(x1, t) * dSigma_SD(x2, t) / dSigma_el(t). Elastic using only Pomerons.

Minimal fall-off relative to t = 0 value.

Optionally dampen with 1 / (1 + exp( -p * (y - y_gap))).

Optionally multiply by s-dependent factor.

Done.

Reimplemented from SigmaTotAux.

double dsigmaSD	(	double	xi,
		double	t,
		bool	= `true`,
		int	= `0`
	)

virtual

Differential single diffractive cross section.

Variations on differential SD cross sections xi * dsigma / dxi dt.

Calculate core SD cross section.

Optionally require falloff at least like exp(bMin * t);

Optionally dampen with 1 / (1 + exp( -p * (y - y_gap))).

Optionally multiply by s-dependent factor.

Done.

Reimplemented from SigmaTotAux.

void init ( Info * infoPtrIn )

virtual

Initialize data members.

Use shorthand for settings

Save pointer.

Common setup.

Allow Couplomb corrections for elastic scattering.

Setup for single diffraction.

Setup for double diffraction.

Setup for central diffraction.

Setup to dampen diffractive events with small rapidity gaps.

Setup to force minimal t fall-off like exp(b_min * t).

Implements SigmaTotAux.

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

include/Pythia8/SigmaTotal.h
src/SigmaTotal.cc

Public Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation