Kinematics generator for HELepton. More...

#include <HELeptonKinematicsGenerator.h>

Inheritance diagram for genie::HELeptonKinematicsGenerator:

Collaboration diagram for genie::HELeptonKinematicsGenerator:

Public Member Functions
	HELeptonKinematicsGenerator ()

	HELeptonKinematicsGenerator (string config)

	~HELeptonKinematicsGenerator ()

void	ProcessEventRecord (GHepRecord *event_rec) const

void	Configure (const Registry &config)

void	Configure (string config)

Public Member Functions inherited from genie::EventRecordVisitorI
virtual	~EventRecordVisitorI ()

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	ComputeMaxXSec (const Interaction *in) const

double	Energy (const Interaction *in) const

Private Attributes
double	fDeltaN1NuE

double	fDeltaN1NuMu

double	fDeltaN1NuTau

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::KineGeneratorWithCache
	KineGeneratorWithCache ()

	KineGeneratorWithCache (string name)

	KineGeneratorWithCache (string name, string config)

	~KineGeneratorWithCache ()

virtual double	ComputeMaxXSec (const Interaction *in, const int nkey) const

virtual double	MaxXSec (GHepRecord *evrec, const int nkey=0) const

virtual double	FindMaxXSec (const Interaction *in, const int nkey=0) const

virtual void	CacheMaxXSec (const Interaction *in, double xsec, const int nkey=0) const

virtual CacheBranchFx *	AccessCacheBranch (const Interaction *in, const int nkey=0) const

virtual void	AssertXSecLimits (const Interaction *in, double xsec, double xsec_max) const

Protected Member Functions inherited from genie::EventRecordVisitorI
	EventRecordVisitorI ()

	EventRecordVisitorI (string name)

	EventRecordVisitorI (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::KineGeneratorWithCache
const XSecAlgorithmI *	fXSecModel

double	fSafetyFactor
	ComputeMaxXSec -> ComputeMaxXSec * fSafetyFactor. More...

std::vector< double >	vSafetyFactors
	MaxXSec -> MaxXSec * fSafetyFactors[nkey]. More...

int	fNumOfSafetyFactors
	Number of given safety factors. More...

std::vector< string >	vInterpolatorTypes
	Type of interpolator for each key in a branch. More...

int	fNumOfInterpolatorTypes
	Number of given interpolators types. More...

double	fMaxXSecDiffTolerance
	max{100(xsec-maxxsec)/.5(xsec+maxxsec)} if xsec>maxxsec More...

double	fEMin
	min E for which maxxsec is cached - forcing explicit calc. More...

bool	fGenerateUniformly
	uniform over allowed phase space + event weight? 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

Kinematics generator for HELepton.

Author: Alfonso Garcia <aagarciasoto km3net.de> IFIC & Harvard University

Created:: Dec 8, 2021

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

Definition at line 26 of file HELeptonKinematicsGenerator.h.

Constructor & Destructor Documentation

HELeptonKinematicsGenerator::HELeptonKinematicsGenerator ( )

Definition at line 34 of file HELeptonKinematicsGenerator.cxx.

                                                          :
 KineGeneratorWithCache("genie::HELeptonKinematicsGenerator")
 {
 
 }

HELeptonKinematicsGenerator::HELeptonKinematicsGenerator ( string config )

Definition at line 40 of file HELeptonKinematicsGenerator.cxx.

                                                                       :
 KineGeneratorWithCache("genie::HELeptonKinematicsGenerator", config)
 {
 
 }

HELeptonKinematicsGenerator::~HELeptonKinematicsGenerator ( )

Definition at line 46 of file HELeptonKinematicsGenerator.cxx.

 {
 
 }

Member Function Documentation

double HELeptonKinematicsGenerator::ComputeMaxXSec ( const Interaction * in ) const

privatevirtual

Implements genie::KineGeneratorWithCache.

Definition at line 210 of file HELeptonKinematicsGenerator.cxx.

References genie::Interaction::AsString(), genie::KineGeneratorWithCache::fSafetyFactor, genie::KineGeneratorWithCache::fXSecModel, genie::ProcessInfo::IsPhotonCoherent(), genie::Interaction::KinePtr(), genie::kKVn1, genie::kKVn2, genie::kKVn3, genie::kPSn1n2fE, genie::kPSn1n2n3fE, pDEBUG, genie::Interaction::ProcInfo(), genie::Kinematics::SetKV(), SLOG, and genie::XSecAlgorithmI::XSec().

 {
 // Computes the maximum differential cross section in the requested phase
 // space. This method overloads KineGeneratorWithCache::ComputeMaxXSec
 // method and the value is cached at a circular cache branch for retrieval
 // during subsequent event generation.
 // The computed max differential cross section does not need to be the exact
 // maximum. The number used in the rejection method will be scaled up by a
 // safety factor. But it needs to be fast - do not use a very small y step.
 
   double max_xsec = -1.0;
   
   ROOT::Math::Minimizer * min = ROOT::Math::Factory::CreateMinimizer("Minuit");
 
   const ProcessInfo & proc_info  = interaction->ProcInfo();
   if(proc_info.IsPhotonCoherent()) {
 
     utils::gsl::d2Xsec_dn1dn2dn3_E f(fXSecModel,interaction,-1);
     min->SetFunction( f );
     min->SetMaxFunctionCalls(10000);
     min->SetTolerance(0.05);
 
     min->SetFixedVariable   ( 0, "n1",   1.);
     min->SetLimitedVariable ( 1, "n2",   0.,   0.01,  0., 1.);
     min->SetLimitedVariable ( 2, "n3",   0.,   0.01,  0., 1.);
     min->Minimize();
     min->SetFixedVariable   ( 0, "n1",   1.);
     min->SetLimitedVariable ( 1, "n2",   min->X()[1],   0.01,  TMath::Max(0.,min->X()[1]-0.1), TMath::Min(1.,min->X()[1]+0.1));
     min->SetLimitedVariable ( 2, "n3",   min->X()[2],   0.01,  TMath::Max(0.,min->X()[2]-0.1), TMath::Min(1.,min->X()[2]+0.1));
     min->Minimize();
     interaction->KinePtr()->SetKV(kKVn1,min->X()[0]);
     interaction->KinePtr()->SetKV(kKVn2,min->X()[1]);
     interaction->KinePtr()->SetKV(kKVn3,min->X()[2]);
     SLOG("HELeptonKinematics", pDEBUG) << "Minimum found -> n1: 1, n2: " << min->X()[1] << ", n3: " << min->X()[2] << ", xsec: " << fXSecModel->XSec(interaction, kPSn1n2n3fE);
     max_xsec = TMath::Max(fXSecModel->XSec(interaction, kPSn1n2n3fE),max_xsec);
 
     min->SetFixedVariable   ( 0, "n1",   -1.);
     min->SetLimitedVariable ( 1, "n2",   0.,   0.01,  0., 1.);
     min->SetLimitedVariable ( 2, "n3",   0.,   0.01,  0., 1.);
     min->Minimize();
     min->SetFixedVariable   ( 0, "n1",   -1.);
     min->SetLimitedVariable ( 1, "n2",   min->X()[1],   0.01,  TMath::Max(0.,min->X()[1]-0.1), TMath::Min(1.,min->X()[1]+0.1));
     min->SetLimitedVariable ( 2, "n3",   min->X()[2],   0.01,  TMath::Max(0.,min->X()[2]-0.1), TMath::Min(1.,min->X()[2]+0.1));
     interaction->KinePtr()->SetKV(kKVn1,min->X()[0]);
     interaction->KinePtr()->SetKV(kKVn2,min->X()[1]);
     interaction->KinePtr()->SetKV(kKVn3,min->X()[2]);
     SLOG("HELeptonKinematics", pDEBUG) << "Minimum found -> n1: -1, n2: " << min->X()[1] << ", n3: " << min->X()[2] << ", xsec: " << fXSecModel->XSec(interaction, kPSn1n2n3fE);
     max_xsec = TMath::Max(fXSecModel->XSec(interaction, kPSn1n2n3fE),max_xsec);
 
   } 
   else {
 
     const int Nscan = 100;
     const int n1min = -1.;
     const int n1max =  1.;
     const int n2min =  0.;
     const int n2max =  1.;
     const double dn1 = (n1max-n1min)/(double)Nscan;
     const double dn2 = (n2max-n2min)/(double)
     Nscan;
 
     double scan_n1 = 0.;
     double scan_n2 = 0.;
     for (int i=0; i<Nscan; i++) {
       double n1 = n1min + dn1*i;
       for (int j=0; j<Nscan; j++) {
         double n2 = n2min + dn2*j;
         interaction->KinePtr()->SetKV(kKVn1,n1);
         interaction->KinePtr()->SetKV(kKVn2,n2);
         double dxsec = fXSecModel->XSec(interaction, kPSn1n2fE);
         if ( dxsec > max_xsec ) {
           scan_n1 = n1;
           scan_n2 = n2;
           max_xsec = dxsec;
         }    
       }    
     }
 
     utils::gsl::d2Xsec_dn1dn2_E f(fXSecModel,interaction,-1);
     min->SetFunction( f );
     min->SetMaxFunctionCalls(10000);
     min->SetTolerance(0.05);
     min->SetLimitedVariable ( 0, "n1", scan_n1, 0.001, TMath::Max(-1.,scan_n1-0.1), TMath::Min(1.,scan_n1+0.1));
     min->SetLimitedVariable ( 1, "n2", scan_n2,   0.1, TMath::Max(-0.,scan_n2-0.1), TMath::Min(1.,scan_n2+0.1));
     min->Minimize();
     interaction->KinePtr()->SetKV(kKVn1,min->X()[0]);
     interaction->KinePtr()->SetKV(kKVn2,min->X()[1]);
     max_xsec = fXSecModel->XSec(interaction, kPSn1n2fE);
     SLOG("HELeptonKinematics", pDEBUG) << "Minimum found -> n1: " << min->X()[0] << ", n2: " << min->X()[1];
 
   }
 
   // Apply safety factor, since value retrieved from the cache might
   // correspond to a slightly different energy.
   max_xsec *= fSafetyFactor;
 
   SLOG("HELeptonKinematics", pDEBUG) << interaction->AsString();
   SLOG("HELeptonKinematics", pDEBUG) << "Max xsec in phase space = " << max_xsec;
   SLOG("HELeptonKinematics", pDEBUG) << "Computed using alg = " << *fXSecModel;
 
   return max_xsec;
 }

void HELeptonKinematicsGenerator::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 324 of file HELeptonKinematicsGenerator.cxx.

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

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

void HELeptonKinematicsGenerator::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 330 of file HELeptonKinematicsGenerator.cxx.

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

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

double HELeptonKinematicsGenerator::Energy ( const Interaction * in ) const

privatevirtual

Reimplemented from genie::KineGeneratorWithCache.

Definition at line 314 of file HELeptonKinematicsGenerator.cxx.

References genie::Interaction::InitState(), genie::kRfLab, and genie::InitialState::ProbeE().

 {
 // Override the base class Energy() method to cache the max xsec for the
 // neutrino energy in the LAB rather than in the hit nucleon rest frame.
 
   const InitialState & init_state = interaction->InitState();
   double E = init_state.ProbeE(kRfLab);
   return E;
 }

void HELeptonKinematicsGenerator::LoadConfig ( void )

private

Definition at line 336 of file HELeptonKinematicsGenerator.cxx.

References fDeltaN1NuE, fDeltaN1NuMu, fDeltaN1NuTau, genie::KineGeneratorWithCache::fMaxXSecDiffTolerance, genie::KineGeneratorWithCache::fSafetyFactor, and genie::Algorithm::GetParamDef().

Referenced by Configure().

 {
 // Reads its configuration data from its configuration Registry and loads them
 // in private data members to avoid looking up at the Registry all the time.
 
   //-- Safety factor for the maximum differential cross section
   GetParamDef( "MaxXSec-SafetyFactor", fSafetyFactor,  2. ) ;
 
   //-- Maximum allowed fractional cross section deviation from maxim cross
   //   section used in rejection method
   GetParamDef( "MaxXSec-DiffTolerance", fMaxXSecDiffTolerance, 999999. ) ;
     assert(fMaxXSecDiffTolerance>=0);
 
   //-- Sampling range for n1 variable
   GetParamDef( "Delta-N1-NuE",   fDeltaN1NuE,   0. ) ;
   GetParamDef( "Delta-N1-NuMu",  fDeltaN1NuMu,  0. ) ;
   GetParamDef( "Delta-N1-NuTau", fDeltaN1NuTau, 0. ) ;
 
 
 }

void HELeptonKinematicsGenerator::ProcessEventRecord ( GHepRecord * event_rec ) const

virtual

Implements genie::EventRecordVisitorI.

Definition at line 51 of file HELeptonKinematicsGenerator.cxx.

References genie::KineGeneratorWithCache::AssertXSecLimits(), genie::Kinematics::ClearRunningValues(), genie::EventGeneratorI::CrossSectionAlg(), genie::GHepRecord::EventFlags(), fDeltaN1NuE, fDeltaN1NuMu, fDeltaN1NuTau, genie::KineGeneratorWithCache::fGenerateUniformly, genie::KineGeneratorWithCache::fXSecModel, genie::Interaction::InitState(), genie::RunningThreadInfo::Instance(), genie::RandomGen::Instance(), genie::pdg::IsNuE(), genie::pdg::IsNuMu(), genie::pdg::IsNuTau(), genie::ProcessInfo::IsPhotonCoherent(), genie::Interaction::KinePtr(), genie::kKineGenErr, genie::kKVn1, genie::kKVn2, genie::kKVn3, genie::kPSn1n2fE, genie::kPSn1n2n3fE, LOG, genie::KineGeneratorWithCache::MaxXSec(), pDEBUG, pINFO, pNOTICE, genie::InitialState::ProbePdg(), genie::Interaction::ProcInfo(), pWARN, genie::RandomGen::RndKine(), genie::RunningThreadInfo::RunningThread(), genie::GHepRecord::SetDiffXSec(), genie::Kinematics::SetKV(), genie::exceptions::EVGThreadException::SetReason(), genie::GHepRecord::Summary(), genie::exceptions::EVGThreadException::SwitchOnFastForward(), and genie::XSecAlgorithmI::XSec().

 {
   if(fGenerateUniformly) {
     LOG("HELeptonKinematics", pNOTICE)
           << "Generating kinematics uniformly over the allowed phase space";
   }
 
   //-- Get the random number generators
   RandomGen * rnd = RandomGen::Instance();
 
   //-- Access cross section algorithm for running thread
   RunningThreadInfo * rtinfo = RunningThreadInfo::Instance();
   const EventGeneratorI * evg = rtinfo->RunningThread();
   fXSecModel = evg->CrossSectionAlg();
 
   Interaction * interaction = evrec->Summary();
 
   //-- For the subsequent kinematic selection with the rejection method:
   //   Calculate the max differential cross section or retrieve it from the
   //   cache. Throw an exception and quit the evg thread if a non-positive
   //   value is found.
   //   If the kinematics are generated uniformly over the allowed phase
   //   space the max xsec is irrelevant
   double xsec_max = this->MaxXSec(evrec);
 
   const ProcessInfo & proc_info  = interaction->ProcInfo();
   if(proc_info.IsPhotonCoherent()) {
 
     double nupdg = interaction->InitState().ProbePdg(); 
 
     double n2min =  0.;
     double n2max =  1.;
     double n3min =  0.;
     double n3max =  1.;
     double dn2   = n2max-n2min;
     double dn3   = n3max-n3min;
 
     double n1max = 0.;
     double n1min = 0.;
     if      (pdg::IsNuE  (TMath::Abs(nupdg))) { n1min = 1.-fDeltaN1NuE;   n1max = 1.+fDeltaN1NuE; }
     else if (pdg::IsNuMu (TMath::Abs(nupdg))) { n1min = 1.-fDeltaN1NuMu;  n1max = 1.+fDeltaN1NuMu; }
     else if (pdg::IsNuTau(TMath::Abs(nupdg))) { n1min = 1.-fDeltaN1NuTau; n1max = 1.+fDeltaN1NuTau; }
     double dn1 = n1max-n1min;
 
 
     //-- Try to select a valid inelastisity y
     double xsec = -1;
     unsigned int iter = 0;
     bool accept = false;
     
     while(1) {
       iter++;
       if(iter > 1000000) {
         LOG("HELeptonKinematics", pWARN)
               << "*** Could not select a valid y after "
                                               << iter << " iterations";
         evrec->EventFlags()->SetBitNumber(kKineGenErr, true);
         genie::exceptions::EVGThreadException exception;
         exception.SetReason("Couldn't select kinematics");
         exception.SwitchOnFastForward();
         throw exception;
       }
 
       double n2 = n2min + dn2 * rnd->RndKine().Rndm();
       double n3 = n3min + dn3 * rnd->RndKine().Rndm();
       double n1 = n1min + dn1 * rnd->RndKine().Rndm();
       n1 = (n1>1.) ? n1-2. : n1;
 
       interaction->KinePtr()->SetKV(kKVn1,n1);
       interaction->KinePtr()->SetKV(kKVn2,n2);
       interaction->KinePtr()->SetKV(kKVn3,n3);
 
       LOG("HELeptonKinematics", pDEBUG) << "Trying: n1 = " << n1 << ", n2 = " << n2 << ", n3 = " << n3;
 
       //-- computing cross section for the current kinematics
       xsec = fXSecModel->XSec(interaction, kPSn1n2n3fE);
 
       this->AssertXSecLimits(interaction, xsec, xsec_max);
 
       double t = xsec_max * rnd->RndKine().Rndm();
       LOG("HELeptonKinematics", pDEBUG) << "xsec= "<< xsec<< ", J= 1, Rnd= "<< t;
 
       accept = (t<xsec);
 
       //-- If the generated kinematics are accepted, finish-up module's job
       if(accept) {
         LOG("HELeptonKinematics", pINFO) << "Selected: n1 = " << n1 << ", n2 = " << n2 << ", n3 = " << n3;
 
         // set the cross section for the selected kinematics
         evrec->SetDiffXSec(xsec,kPSn1n2n3fE);
 
         // lock selected kinematics & clear running values
         interaction->KinePtr()->ClearRunningValues();
 
         return;
       }
     }// iterations
 
   }
   else {
     double n1min = -1.;
     double n1max =  1.;
     double n2min =  0.;
     double n2max =  1.;
     double dn1   = n1max-n1min;
     double dn2   = n2max-n2min;
 
     //-- Try to select a valid inelastisity y
     double xsec = -1;
     unsigned int iter = 0;
     bool accept = false;
     
     while(1) {
       iter++;
       if(iter > 1000000) {
         LOG("HELeptonKinematics", pWARN)
               << "*** Could not select a valid y after "
                                               << iter << " iterations";
         evrec->EventFlags()->SetBitNumber(kKineGenErr, true);
         genie::exceptions::EVGThreadException exception;
         exception.SetReason("Couldn't select kinematics");
         exception.SwitchOnFastForward();
         throw exception;
       }
 
       double n1 = n1min + dn1 * rnd->RndKine().Rndm();
       double n2 = n2min + dn2 * rnd->RndKine().Rndm();
       interaction->KinePtr()->SetKV(kKVn1,n1);
       interaction->KinePtr()->SetKV(kKVn2,n2);
 
       LOG("HELeptonKinematics", pDEBUG) << "Trying: n1 = " << n1 << ", n2 = " << n2;
 
       //-- computing cross section for the current kinematics
       xsec = fXSecModel->XSec(interaction, kPSn1n2fE);
 
       this->AssertXSecLimits(interaction, xsec, xsec_max);
 
       double t = xsec_max * rnd->RndKine().Rndm();
       LOG("HELeptonKinematics", pDEBUG) << "xsec= "<< xsec<< ", J= 1, Rnd= "<< t;
 
       accept = (t<xsec);
 
       //-- If the generated kinematics are accepted, finish-up module's job
       if(accept) {
         LOG("HELeptonKinematics", pINFO) << "Selected: n1 = " << n1 << ", n2 = " << n2;
 
         // set the cross section for the selected kinematics
         evrec->SetDiffXSec(xsec,kPSn1n2fE);
 
         // lock selected kinematics & clear running values
         interaction->KinePtr()->ClearRunningValues();
 
         return;
       }
     }// iterations
 
   }
 }