Computes the differential cross section for an exclusive 1-pion reaction through resonance neutrinoproduction according to the Rein-Sehgal model. More...

#include <ReinSehgalSPPPXSec.h>

Inheritance diagram for genie::ReinSehgalSPPPXSec:

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Collaboration diagram for genie::ReinSehgalSPPPXSec:

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Public Member Functions
	ReinSehgalSPPPXSec ()

	ReinSehgalSPPPXSec (string config)

virtual	~ReinSehgalSPPPXSec ()

double	XSec (const Interaction *i, KinePhaseSpace_t k) const
	Compute the cross section for the input interaction. More...

double	Integral (const Interaction *i) const

bool	ValidProcess (const Interaction *i) const
	Can this cross section algorithm handle the input process? More...

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? More...

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. More...

virtual AlgStatus_t	GetStatus (void) const
	Get algorithm status. More...

virtual bool	AllowReconfig (void) const

virtual AlgCmp_t	Compare (const Algorithm *alg) const
	Compare with input algorithm. More...

virtual void	SetId (const AlgId &id)
	Set algorithm ID. More...

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. More...

Private Member Functions
void	LoadConfig (void)

double	XSecNRES (const Interaction *i, KinePhaseSpace_t k) const

double	XSec1RES (const Interaction *i, KinePhaseSpace_t k) const

Private Attributes
BaryonResList	fResList

const XSecAlgorithmI *	fSingleResXSecModel

const XSecIntegratorI *	fXSecIntegrator

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. More...

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. More...

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. More...

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 More...

int	AddLowRegistry (Registry *rp, bool owns=true)
	add registry with lowest priority, also update ownership More...

int	MergeTopRegistry (const Registry &r)

int	AddTopRegisties (const vector< Registry * > &rs, bool owns=false)
	Add registries with top priority, also udated Ownerships. More...

Protected Attributes inherited from genie::Algorithm
bool	fAllowReconfig

bool	fOwnsSubstruc
	true if it owns its substructure (sub-algs,...) More...

AlgId	fID
	algorithm name and configuration set More...

vector< Registry * >	fConfVect

vector< bool >	fOwnerships
	ownership for every registry in fConfVect More...

AlgStatus_t	fStatus
	algorithm execution status More...

AlgMap *	fOwnedSubAlgMp
	local pool for owned sub-algs (taken out of the factory pool) More...

Detailed Description

Computes the differential cross section for an exclusive 1-pion reaction through resonance neutrinoproduction according to the Rein-Sehgal model.

      The cross section is computed for an input list of resonances
      as the sum of the Rein-Sehgal single resonance cross sections
      weighted:

      \li With the value of their Breit-Wigner distributions at the given
          W,Q^2 (The code for BW weighting is included in the single
          resonance cross section algorithm. The user needs to make sure
          that he does not run the single resonance cross section code with
          a configuration that inhibits weighting).

      \li With the isospin Glebsch-Gordon coefficient determining the
          contribution of each resonance to the exclusive final state.

      \li With the BR for the produced resonance to decay into the given
          exclusive final state.

      In this algorithm we follow the non-coherent approach: we sum
      the weighted resonance production cross sections rather than the
      resonance production amplitudes.

      Is a concrete implementation of the XSecAlgorithmI interface.

References:: D.Rein and L.M.Sehgal, Neutrino Excitation of Baryon Resonances and Single Pion Production, Ann.Phys.133, 79 (1981)

Author: Costas Andreopoulos <c.andreopoulos cern.ch> University of Liverpool

Created:: November 22, 2004

License:: Copyright (c) 2003-2024, The GENIE Collaboration For the full text of the license visit http://copyright.genie-mc.org

Definition at line 55 of file ReinSehgalSPPPXSec.h.

Constructor & Destructor Documentation

ReinSehgalSPPPXSec::ReinSehgalSPPPXSec ( )

Definition at line 27 of file ReinSehgalSPPPXSec.cxx.

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

ReinSehgalSPPPXSec::ReinSehgalSPPPXSec ( string config )

Definition at line 33 of file ReinSehgalSPPPXSec.cxx.

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

ReinSehgalSPPPXSec::~ReinSehgalSPPPXSec ( )

virtual

Definition at line 39 of file ReinSehgalSPPPXSec.cxx.

 {
 
 }

Member Function Documentation

void ReinSehgalSPPPXSec::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 160 of file ReinSehgalSPPPXSec.cxx.

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

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

void ReinSehgalSPPPXSec::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 166 of file ReinSehgalSPPPXSec.cxx.

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

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

double ReinSehgalSPPPXSec::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 137 of file ReinSehgalSPPPXSec.cxx.

References fXSecIntegrator, and genie::XSecIntegratorI::Integrate().

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

void ReinSehgalSPPPXSec::LoadConfig ( void )

private

Definition at line 172 of file ReinSehgalSPPPXSec.cxx.

References genie::BaryonResList::Clear(), genie::BaryonResList::DecodeFromNameList(), fResList, fSingleResXSecModel, fXSecIntegrator, genie::Algorithm::GetParam(), and genie::Algorithm::SubAlg().

Referenced by Configure().

 {
 // load the single resonance cross section algorithm specified in the config.
 
   fSingleResXSecModel =
    dynamic_cast<const XSecAlgorithmI *> (this->SubAlg("SingleRESDiffXSecAlg"));
   assert(fSingleResXSecModel);
 
   //-- Create a BaryonResList by decoding the resonance list from
   //   the XML input
   //   The list of resonances can be specified as a string with
   //   comma separated resonance names (eg "P33(1233),S11(1535),D13(1520)")
   //   The BaryonResList can also decode lists of pdg-codes or
   //   resonance-ids (Resonance_t enumerations).
   //   Support for this will be added here as well.
 
   fResList.Clear();
 
 
   string resonances ;
   GetParam( "ResonanceNameList", resonances ) ;
   fResList.DecodeFromNameList(resonances);
 
   //-- load the differential cross section integrator
   fXSecIntegrator =
       dynamic_cast<const XSecIntegratorI *> (this->SubAlg("XSec-Integrator"));
   assert(fXSecIntegrator);
 }

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

virtual

Can this cross section algorithm handle the input process?

Implements genie::XSecAlgorithmI.

Definition at line 142 of file ReinSehgalSPPPXSec.cxx.

References genie::SppChannel::AsString(), genie::SppChannel::FromInteraction(), genie::kISkipProcessChk, genie::kSppNull, LOG, pDEBUG, and pERROR.

Referenced by XSec().

 {
   if(interaction->TestBit(kISkipProcessChk)) return true;
 
   //-- Get the requested SPP channel
   SppChannel_t spp_channel = SppChannel::FromInteraction(interaction);
   if( spp_channel == kSppNull ) {
     LOG("ReinSehgalSpp", pERROR)
             << "\n *** Insufficient SPP exclusive final state information!";
     return false;
   }
 #ifdef __GENIE_LOW_LEVEL_MESG_ENABLED__
   LOG("ReinSehgalSpp", pDEBUG)
                        << "Reaction: " << SppChannel::AsString(spp_channel);
 #endif
   return true;
 }

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

virtual

Compute the cross section for the input interaction.

Implements genie::XSecAlgorithmI.

Definition at line 44 of file ReinSehgalSPPPXSec.cxx.

References genie::utils::res::AsString(), genie::Interaction::ExclTag(), genie::BaryonResList::Find(), fResList, fSingleResXSecModel, genie::kNoResonance, LOG, pDEBUG, pWARN, genie::XclsTag::Resonance(), genie::XSecAlgorithmI::ValidKinematics(), ValidProcess(), genie::XSecAlgorithmI::XSec(), and XSecNRES().

 {
   if(! this -> ValidProcess    (interaction) ) return 0.;
   if(! this -> ValidKinematics (interaction) ) return 0.;
 #ifdef __GENIE_LOW_LEVEL_MESG_ENABLED__
   LOG("ReinSehgalSpp", pDEBUG)
                  << "Computing a cross section for " << *interaction;
 #endif
   //-- Check whether a resonance has been specified
   //   If yes, compute only the contribution of this resonance at the
   //   specified exclusive state
 
   Resonance_t inpres = interaction->ExclTag().Resonance();
   if(inpres != kNoResonance) {
 #ifdef __GENIE_LOW_LEVEL_MESG_ENABLED__
         LOG("ReinSehgalSpp", pDEBUG)
                << "Computing only the contribution from: " << utils::res::AsString(inpres);
 #endif
     if(!fResList.Find(inpres)) {
        LOG("ReinSehgalSpp", pWARN)
            << "Resonance: " << utils::res::AsString(inpres) << " was not found in my list";
        return 0;
     }
     //-- Compute the contribution of this resonance
     //-- Get the Breit-Wigner weighted xsec for exciting the resonance
 
     return fSingleResXSecModel->XSec(interaction,kps);
   }
 
   //-- Loop over the specified list of baryon resonances and compute
   //   the cross section for the input exclusive channel
 
   return this->XSecNRES(interaction,kps);
 }

double genie::ReinSehgalSPPPXSec::XSec1RES	(	const Interaction *	i,
		KinePhaseSpace_t	k
	)		const

private

double ReinSehgalSPPPXSec::XSecNRES	(	const Interaction *	i,
		KinePhaseSpace_t	k
	)		const

private

Definition at line 80 of file ReinSehgalSPPPXSec.cxx.

References genie::utils::res::AsString(), genie::SppChannel::AsString(), genie::SppChannel::BranchingRatio(), genie::Interaction::ExclTagPtr(), fResList, genie::SppChannel::FromInteraction(), fSingleResXSecModel, genie::SppChannel::IsospinWeight(), genie::kNoResonance, LOG, genie::BaryonResList::NResonances(), pDEBUG, genie::BaryonResList::ResonanceId(), genie::XclsTag::SetResonance(), and genie::XSecAlgorithmI::XSec().

Referenced by XSec().

 {
 // computes the 1pi cros section taking into account the contribution of all
 // specified baryon resonances
 
   unsigned int nres = fResList.NResonances();
 #ifdef __GENIE_LOW_LEVEL_MESG_ENABLED__
   LOG("ReinSehgalSpp", pDEBUG)
     << "Computing SPP cross section using " << nres << " resonances";
 #endif
 
   //-- Get 1pi exclusive channel
   SppChannel_t spp_channel = SppChannel::FromInteraction(interaction);
 #ifdef __GENIE_LOW_LEVEL_MESG_ENABLED__
   LOG("ReinSehgalSpp", pDEBUG)
               << "SPP channel " << SppChannel::AsString(spp_channel);
 #endif
 
   double xsec = 0;
   for(unsigned int ires = 0; ires < nres; ires++) {
 
      //-- Get next resonance from the resonance list
      Resonance_t res = fResList.ResonanceId(ires);
 
      //-- Set current resonance to interaction object
      interaction->ExclTagPtr()->SetResonance(res);
 
      //-- Get the BR for the (resonance) -> (exclusive final state)
          double br = SppChannel::BranchingRatio(/*spp_channel,*/ res);
 
          //-- Get the Isospin Clebsch-Gordon coefficient for the given resonance
          //   and exclusive final state
          double igg = SppChannel::IsospinWeight(spp_channel, res);
 
          //-- Compute the weighted xsec
          //  (total weight = Breit-Wigner * BR * isospin Clebsch-Gordon)
          double res_xsec_contrib = fSingleResXSecModel->XSec(interaction,kps)*br*igg;
 #ifdef __GENIE_LOW_LEVEL_MESG_ENABLED__
          LOG("ReinSehgalSpp", pDEBUG)
      << "Contrib. from [" << utils::res::AsString(res) << "] = "
      << "<Clebsch-Gordon = " << igg
      << "> * <BR(->1pi) = " << br
      << "> * <Breit-Wigner * d^nxsec/dK^n = " << rxsec
      << "> = " << res_xsec_contrib;
 #endif
 
      //-- Add contribution of this resonance to the cross section
      xsec += res_xsec_contrib;
   }
 
   //-- delete the resonance from the input interaction
   interaction->ExclTagPtr()->SetResonance(kNoResonance);
 
   return xsec;
 }