Computes the double differential Cross Section for HEDIS.
Is a concrete implementation of the XSecAlgorithmI interface. More...

#include <HEDISPXSec.h>

Inheritance diagram for genie::HEDISPXSec:

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Collaboration diagram for genie::HEDISPXSec:

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Public Member Functions
	HEDISPXSec ()
	HEDISPXSec (string config)
virtual	~HEDISPXSec ()
double	XSec (const Interaction *i, KinePhaseSpace_t k) const
	Compute the cross section for the input interaction.
double	Integral (const Interaction *i) const
bool	ValidProcess (const Interaction *i) const
	Can this cross section algorithm handle the input process?
void	Configure (const Registry &config)
void	Configure (string config)
Public Member Functions inherited from genie::XSecAlgorithmI
virtual	~XSecAlgorithmI ()
virtual bool	ValidKinematics (const Interaction *i) const
	Is the input kinematical point a physically allowed one?
Public Member Functions inherited from genie::Algorithm
virtual	~Algorithm ()
virtual void	FindConfig (void)
virtual const Registry &	GetConfig (void) const
Registry *	GetOwnedConfig (void)
virtual const AlgId &	Id (void) const
	Get algorithm ID.
virtual AlgStatus_t	GetStatus (void) const
	Get algorithm status.
virtual bool	AllowReconfig (void) const
virtual AlgCmp_t	Compare (const Algorithm *alg) const
	Compare with input algorithm.
virtual void	SetId (const AlgId &id)
	Set algorithm ID.
virtual void	SetId (string name, string config)
const Algorithm *	SubAlg (const RgKey &registry_key) const
void	AdoptConfig (void)
void	AdoptSubstructure (void)
virtual void	Print (ostream &stream) const
	Print algorithm info.

Private Member Functions
void	LoadConfig (void)
double	ds_dxdy (SF_xQ2 sf, double x, double y) const
double	ds_dxdy_mass (SF_xQ2 sf, double x, double y, double e, double mt, double ml2) const

Private Attributes
const XSecIntegratorI *	fXSecIntegrator
	diff. xsec integrator
double	fWmin
	Minimum value of W.
bool	fMassTerms
	Account for second order effects in DDxsec.
SF_info	fSFinfo
	Information used to computed SF.

Additional Inherited Members
Static Public Member Functions inherited from genie::Algorithm
static string	BuildParamVectKey (const std::string &comm_name, unsigned int i)
static string	BuildParamVectSizeKey (const std::string &comm_name)
static string	BuildParamMatKey (const std::string &comm_name, unsigned int i, unsigned int j)
static string	BuildParamMatRowSizeKey (const std::string &comm_name)
static string	BuildParamMatColSizeKey (const std::string &comm_name)
Protected Member Functions inherited from genie::XSecAlgorithmI
	XSecAlgorithmI ()
	XSecAlgorithmI (string name)
	XSecAlgorithmI (string name, string config)
Protected Member Functions inherited from genie::Algorithm
	Algorithm ()
	Algorithm (string name)
	Algorithm (string name, string config)
void	Initialize (void)
void	DeleteConfig (void)
void	DeleteSubstructure (void)
Registry *	ExtractLocalConfig (const Registry &in) const
Registry *	ExtractLowerConfig (const Registry &in, const string &alg_key) const
	Split an incoming configuration Registry into a block valid for the sub-algo identified by alg_key.
template<class T>
bool	GetParam (const RgKey &name, T &p, bool is_top_call=true) const
template<class T>
bool	GetParamDef (const RgKey &name, T &p, const T &def) const
template<class T>
int	GetParamVect (const std::string &comm_name, std::vector< T > &v, bool is_top_call=true) const
	Handle to load vectors of parameters.
int	GetParamVectKeys (const std::string &comm_name, std::vector< RgKey > &k, bool is_top_call=true) const
template<class T>
int	GetParamMat (const std::string &comm_name, TMatrixT< T > &mat, bool is_top_call=true) const
	Handle to load matrix of parameters.
template<class T>
int	GetParamMatSym (const std::string &comm_name, TMatrixTSym< T > &mat, bool is_top_call=true) const
int	GetParamMatKeys (const std::string &comm_name, std::vector< RgKey > &k, bool is_top_call=true) const
int	AddTopRegistry (Registry *rp, bool owns=true)
	add registry with top priority, also update ownership
int	AddLowRegistry (Registry *rp, bool owns=true)
	add registry with lowest priority, also update ownership
int	MergeTopRegistry (const Registry &r)
int	AddTopRegisties (const vector< Registry * > &rs, bool owns=false)
	Add registries with top priority, also udated Ownerships.
Protected Attributes inherited from genie::Algorithm
bool	fAllowReconfig
bool	fOwnsSubstruc
	true if it owns its substructure (sub-algs,...)
AlgId	fID
	algorithm name and configuration set
vector< Registry * >	fConfVect
vector< bool >	fOwnerships
	ownership for every registry in fConfVect
AlgStatus_t	fStatus
	algorithm execution status
AlgMap *	fOwnedSubAlgMp
	local pool for owned sub-algs (taken out of the factory pool)

Detailed Description

Computes the double differential Cross Section for HEDIS.
Is a concrete implementation of the XSecAlgorithmI interface.

Author: Alfonso Garcia <alfonsog \at nikhef.nl> NIKHEF

Created:\n August 28, 2019

License:\n Copyright (c) 2003-2025, The GENIE Collaboration: For the full text of the license visit http://copyright.genie-mc.org or see $GENIE/LICENSE

Definition at line 30 of file HEDISPXSec.h.

Constructor & Destructor Documentation

◆ HEDISPXSec() [1/2]

HEDISPXSec::HEDISPXSec ( )

Definition at line 29 of file HEDISPXSec.cxx.

                       :
XSecAlgorithmI("genie::HEDISPXSec")
{
 
}

References genie::XSecAlgorithmI::XSecAlgorithmI().

◆ HEDISPXSec() [2/2]

HEDISPXSec::HEDISPXSec ( string config )

Definition at line 35 of file HEDISPXSec.cxx.

                                    :
XSecAlgorithmI("genie::HEDISPXSec", config)
{
 
}

References genie::XSecAlgorithmI::XSecAlgorithmI().

◆ ~HEDISPXSec()

HEDISPXSec::~HEDISPXSec ( )

virtual

Definition at line 41 of file HEDISPXSec.cxx.

{
 
}

Member Function Documentation

◆ Configure() [1/2]

void HEDISPXSec::Configure ( const Registry & config )

virtual

Configure the algorithm with an external registry The registry is merged with the top level registry if it is owned, Otherwise a copy of it is added with the highest priority

Reimplemented from genie::Algorithm.

Definition at line 178 of file HEDISPXSec.cxx.

{
  Algorithm::Configure(config);
  this->LoadConfig();
}

References genie::Algorithm::Configure(), and LoadConfig().

◆ Configure() [2/2]

void HEDISPXSec::Configure ( string config )

virtual

Configure the algorithm from the AlgoConfigPool based on param_set string given in input An algorithm contains a vector of registries coming from different xml configuration files, which are loaded according a very precise prioriy This methods will load a number registries in order of priority: 1) "Tunable" parameter set from CommonParametes. This is loaded with the highest prioriry and it is designed to be used for tuning procedure Usage not expected from the user. 2) For every string defined in "CommonParame" the corresponding parameter set will be loaded from CommonParameter.xml 3) parameter set specified by the config string and defined in the xml file of the algorithm 4) if config is not "Default" also the Default parameter set from the same xml file will be loaded Effectively this avoids the repetion of a parameter when it is not changed in the requested configuration

Reimplemented from genie::Algorithm.

Definition at line 184 of file HEDISPXSec.cxx.

{
  Algorithm::Configure(config);
  this->LoadConfig();
}

References genie::Algorithm::Configure(), and LoadConfig().

◆ ds_dxdy()

double HEDISPXSec::ds_dxdy	(	SF_xQ2	sf,
		double	x,
		double	y ) const

private

Definition at line 117 of file HEDISPXSec.cxx.

{
 
    // We neglect F4 and F5 and higher order terms.
    double term1 = y * ( x*y );
    double term2 = ( 1 - y );
    double term3 = ( x*y*(1-y/2) );
 
    LOG("HEDISPXSec", pDEBUG) << sf.F1 << "  " << sf.F2 << "  " << sf.F3;
    LOG("HEDISPXSec", pDEBUG) << term1*sf.F1 + term2*sf.F2 + term3*sf.F3;
 
    return fmax( term1*sf.F1 + term2*sf.F2 + term3*sf.F3 , 0.);
 
}

References genie::SF_xQ2::F1, genie::SF_xQ2::F2, genie::SF_xQ2::F3, LOG, and pDEBUG.

Referenced by XSec().

◆ ds_dxdy_mass()

double HEDISPXSec::ds_dxdy_mass	(	SF_xQ2	sf,
		double	x,
		double	y,
		double	e,
		double	mt,
		double	ml2 ) const

private

Definition at line 132 of file HEDISPXSec.cxx.

{
 
    double term1 = y * ( x*y + ml2/2/e/mt );
    double term2 = ( 1 - y - mt*x*y/2/e - ml2/4/e/e );
    double term3 = (x*y*(1-y/2) - y*ml2/4/mt/e);
    double term4 = x*y*ml2/2/mt/e + ml2*ml2/4/mt/mt/e/e;
    double term5 = -1.*ml2/2/mt/e;
 
    double F4 = 0.;
    double F5 = sf.F2/x;
 
    LOG("HEDISPXSec", pDEBUG) << sf.F1 << "  " << sf.F2 << "  " << sf.F3;
    LOG("HEDISPXSec", pDEBUG) << term1*sf.F1 + term2*sf.F2 + term3*sf.F3;
 
    return fmax( term1*sf.F1 + term2*sf.F2 + term3*sf.F3 + term4*F4 + term5*F5 , 0.);
 
}

References e, genie::SF_xQ2::F1, genie::SF_xQ2::F2, genie::SF_xQ2::F3, LOG, and pDEBUG.

Referenced by XSec().

◆ Integral()

double HEDISPXSec::Integral ( const Interaction * i ) const

virtual

Integrate the model over the kinematic phase space available to the input interaction (kinematical cuts can be included)

Implements genie::XSecAlgorithmI.

Definition at line 151 of file HEDISPXSec.cxx.

{
 
  return fXSecIntegrator->Integrate(this,interaction);
 
}

References fXSecIntegrator.

◆ LoadConfig()

void HEDISPXSec::LoadConfig ( void )

private

Definition at line 190 of file HEDISPXSec.cxx.

{
 
  //-- load the differential cross section integrator
  fXSecIntegrator = dynamic_cast<const XSecIntegratorI *> (this->SubAlg("XSec-Integrator"));
  assert(fXSecIntegrator);
 
  // Minimum value of W (typically driven by hadronization limitation)
  GetParam("Xsec-Wmin",       fWmin);
  GetParam("Mass-Terms", fMassTerms);
 
  // Information about Structure Functions
  GetParam("LHAPDF-set",      fSFinfo.LHAPDFset    );
  GetParam("LHAPDF-member",   fSFinfo.LHAPDFmember );
  GetParam("Is-NLO",          fSFinfo.IsNLO        );
  GetParam("Scheme",          fSFinfo.Scheme       );
  GetParam("Quark-Threshold", fSFinfo.QrkThrs      );
  GetParam("NGridX",          fSFinfo.NGridX       );
  GetParam("NGridQ2",         fSFinfo.NGridQ2      );
  GetParam("XGrid-Min",       fSFinfo.XGridMin     );
  GetParam("Q2Grid-Min",      fSFinfo.Q2GridMin    );
  GetParam("Q2Grid-Max",      fSFinfo.Q2GridMax    );
  GetParam("MassW",           fSFinfo.MassW        );
  GetParam("MassZ",           fSFinfo.MassZ        );
  GetParam("Rho",             fSFinfo.Rho          );
  GetParam("Sin2ThW",         fSFinfo.Sin2ThW      );
  GetParam("Mud",             fSFinfo.Vud          );
  GetParam("Mus",             fSFinfo.Vus          );
  GetParam("Mub",             fSFinfo.Vub          );
  GetParam("Mcd",             fSFinfo.Vcd          );
  GetParam("Mcs",             fSFinfo.Vcs          );
  GetParam("Mcb",             fSFinfo.Vcb          );
  GetParam("Mtd",             fSFinfo.Vtd          );
  GetParam("Mts",             fSFinfo.Vts          );
  GetParam("Mtb",             fSFinfo.Vtb          );
 
}

References fMassTerms, fSFinfo, fWmin, fXSecIntegrator, genie::Algorithm::GetParam(), and genie::Algorithm::SubAlg().

Referenced by Configure(), and Configure().

◆ ValidProcess()

bool HEDISPXSec::ValidProcess ( const Interaction * i ) const

virtual

Can this cross section algorithm handle the input process?

Implements genie::XSecAlgorithmI.

Definition at line 158 of file HEDISPXSec.cxx.

{
 
  if(interaction->TestBit(kISkipProcessChk)) return true;
 
  const ProcessInfo & proc_info  = interaction->ProcInfo();
  if(!proc_info.IsDeepInelastic()) return false;
 
  const InitialState & init_state = interaction -> InitState();
  int probe_pdg = init_state.ProbePdg();
  if(!pdg::IsLepton(probe_pdg)) return false;
 
  if(! init_state.Tgt().HitNucIsSet()) return false;
 
  int hitnuc_pdg = init_state.Tgt().HitNucPdg();
  if(!pdg::IsNeutronOrProton(hitnuc_pdg)) return false;
 
  return true;
}

References genie::Target::HitNucIsSet(), genie::Target::HitNucPdg(), genie::ProcessInfo::IsDeepInelastic(), genie::pdg::IsLepton(), genie::pdg::IsNeutronOrProton(), genie::kISkipProcessChk, genie::InitialState::ProbePdg(), genie::Interaction::ProcInfo(), and genie::InitialState::Tgt().

◆ XSec()

double HEDISPXSec::XSec	(	const Interaction *	i,
		KinePhaseSpace_t	k ) const

virtual

Compute the cross section for the input interaction.

Implements genie::XSecAlgorithmI.

Definition at line 46 of file HEDISPXSec.cxx.

{
 
  if(! this -> ValidKinematics (interaction) ) return 0.;
 
  // Load SF tables 
  HEDISStrucFunc * sf_tbl = HEDISStrucFunc::Instance(fSFinfo);
 
  // W limits are computed using kinematics assumption.
  // The lower limit is tuneable because hadronization might have issues at low W (as in PYTHIA6).
  // To be consistent the cross section must be computed in the W range where the events are generated.
  const Kinematics  & kinematics = interaction -> Kine();
  const KPhaseSpace & ps         = interaction -> PhaseSpace();
  double W = kinematics.W();
  Range1D_t Wl  = ps.WLim();
  Wl.min = TMath::Max(Wl.min,fWmin);
  if      ( W<Wl.min ) return 0.;
  else if ( W>Wl.max ) return 0.;
 
  const InitialState & init_state = interaction -> InitState();
 
  double y     = kinematics.y();
  double Q2    = kinematics.Q2();
  double x     = kinematics.x();
  double E     = init_state.ProbeE(kRfLab);
  double Mnuc  = init_state.Tgt().HitNucMass();
  double Mlep2 = TMath::Power(interaction->FSPrimLepton()->Mass(),2);
 
  // Get F1,F2,F3 for particular quark channel and compute differential xsec
  SF_xQ2 sf = sf_tbl->EvalQrkSFLO( interaction, x, Q2 );
  double xsec = (fMassTerms) ? ds_dxdy_mass( sf, x, y, E, Mnuc, Mlep2 ) : ds_dxdy( sf, x, y );
 
  // If NLO is enable we compute sigma_NLO/sigma_LO. Then the quark xsec 
  // is multiplied by this ratio.
  // This is done because at NLO we can only compute the nucleon xsec. But
  // for the hadronization we need the different quark contributions.
  // This could be avoid if a NLO parton showering is introduced.
  if (fSFinfo.IsNLO && xsec>0.) {
    SF_xQ2 sflo  = sf_tbl->EvalNucSFLO(interaction,x,Q2);
    SF_xQ2 sfnlo = sf_tbl->EvalNucSFNLO(interaction,x,Q2);
    double lo  = (fMassTerms) ? ds_dxdy_mass( sflo, x, y, E, Mnuc, Mlep2 ) : ds_dxdy( sflo, x, y );
    if (lo>0.) {
      double nlo = (fMassTerms) ? ds_dxdy_mass( sfnlo, x, y, E, Mnuc, Mlep2 ) : ds_dxdy( sfnlo, x, y );
      xsec *= nlo / lo;
    }
  }
 
  // Compute the front factor
  double propagator = 0;
  if (interaction -> ProcInfo().IsWeakCC()) propagator = TMath::Power( fSFinfo.MassW*fSFinfo.MassW/(Q2+fSFinfo.MassW*fSFinfo.MassW), 2);
  else                                      propagator = TMath::Power( fSFinfo.MassZ*fSFinfo.MassZ/(Q2+fSFinfo.MassZ*fSFinfo.MassZ)/(1.-fSFinfo.Rho), 2);
 
  xsec *= kGF2/(2*kPi*x) * propagator;
 
  LOG("HEDISPXSec", pINFO) << "d2xsec/dxdy[FreeN] (x= " << x  << ", y= " << y << ", Q2= " << Q2 << ") = " << xsec;
 
  // The algorithm computes d^2xsec/dxdy. Check whether variable tranformation is needed
  if( kps!=kPSxQ2fE ) xsec *= utils::kinematics::Jacobian(interaction,kPSxQ2fE,kps);
 
  // If requested return the free nucleon xsec even for input nuclear tgt 
  if( interaction->TestBit(kIAssumeFreeNucleon) ) return xsec;
 
  // Compute nuclear cross section (simple scaling here, corrections must have been included in the structure functions)
  int NNucl = (pdg::IsProton(init_state.Tgt().HitNucPdg())) ? init_state.Tgt().Z() : init_state.Tgt().N(); 
  xsec *= NNucl; 
 
  return xsec;
 
}

References ds_dxdy(), ds_dxdy_mass(), genie::HEDISStrucFunc::EvalNucSFLO(), genie::HEDISStrucFunc::EvalNucSFNLO(), genie::HEDISStrucFunc::EvalQrkSFLO(), fMassTerms, fSFinfo, genie::Interaction::FSPrimLepton(), fWmin, genie::Target::HitNucMass(), genie::Target::HitNucPdg(), genie::HEDISStrucFunc::Instance(), genie::pdg::IsProton(), genie::utils::kinematics::Jacobian(), genie::constants::kGF2, genie::kIAssumeFreeNucleon, genie::constants::kPi, genie::kPSxQ2fE, genie::kRfLab, LOG, genie::Range1D_t::max, genie::Range1D_t::min, genie::Target::N(), pINFO, genie::InitialState::ProbeE(), genie::Kinematics::Q2(), genie::InitialState::Tgt(), genie::XSecAlgorithmI::ValidKinematics(), genie::Kinematics::W(), genie::KPhaseSpace::WLim(), genie::Kinematics::x(), genie::Kinematics::y(), and genie::Target::Z().

Member Data Documentation

◆ fMassTerms

bool genie::HEDISPXSec::fMassTerms

private

Account for second order effects in DDxsec.

Definition at line 55 of file HEDISPXSec.h.

Referenced by LoadConfig(), and XSec().

◆ fSFinfo

SF_info genie::HEDISPXSec::fSFinfo

private

Information used to computed SF.

Definition at line 56 of file HEDISPXSec.h.

Referenced by LoadConfig(), and XSec().

◆ fWmin

double genie::HEDISPXSec::fWmin

private

Minimum value of W.

Definition at line 54 of file HEDISPXSec.h.

Referenced by LoadConfig(), and XSec().

◆ fXSecIntegrator

const XSecIntegratorI* genie::HEDISPXSec::fXSecIntegrator

private

diff. xsec integrator

Definition at line 52 of file HEDISPXSec.h.

Referenced by Integral(), and LoadConfig().

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

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ HEDISPXSec() [1/2]

◆ HEDISPXSec() [2/2]

◆ ~HEDISPXSec()

Member Function Documentation

◆ Configure() [1/2]

◆ Configure() [2/2]

◆ ds_dxdy()

◆ ds_dxdy_mass()

◆ Integral()

◆ LoadConfig()

◆ ValidProcess()

◆ XSec()

Member Data Documentation

◆ fMassTerms

◆ fSFinfo

◆ fWmin

◆ fXSecIntegrator