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genie::AhrensNCELPXSec Class Reference

Differential cross section for v+N / vbar+N elastic scattering.
Is a concrete implementation of the XSecAlgorithmI interface.
. More...

#include <AhrensNCELPXSec.h>

Inheritance diagram for genie::AhrensNCELPXSec:
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Collaboration diagram for genie::AhrensNCELPXSec:
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Public Member Functions

 AhrensNCELPXSec ()
 
 AhrensNCELPXSec (string config)
 
virtual ~AhrensNCELPXSec ()
 
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 param_set)
 
- 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 RegistryGetConfig (void) const
 
RegistryGetOwnedConfig (void)
 
virtual const AlgIdId (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 AlgorithmSubAlg (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)
 

Private Attributes

const XSecIntegratorIfXSecIntegrator
 
double fkAlpha
 
double fkGamma
 
double fEta
 
double fFa0
 
double fMa2
 
double fMv2
 
double fMuP
 
double fMuN
 

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)
 
RegistryExtractLocalConfig (const Registry &in) const
 
RegistryExtractLowerConfig (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...
 
AlgMapfOwnedSubAlgMp
 local pool for owned sub-algs (taken out of the factory pool) More...
 

Detailed Description

Differential cross section for v+N / vbar+N elastic scattering.
Is a concrete implementation of the XSecAlgorithmI interface.
.

References:
R.E.Hendrick and L.Li, Phys.Rev.D 19:779 (1979) L.A.Ahrens et al., Phys.Rev.D 35:785 (1987)
Author
Costas Andreopoulos <c.andreopoulos cern.ch> University of Liverpool
Created:
Fabruary 15, 2005
License:
Copyright (c) 2003-2024, The GENIE Collaboration For the full text of the license visit http://copyright.genie-mc.org

Definition at line 32 of file AhrensNCELPXSec.h.

Constructor & Destructor Documentation

AhrensNCELPXSec::AhrensNCELPXSec ( )

Definition at line 30 of file AhrensNCELPXSec.cxx.

30  :
31 XSecAlgorithmI("genie::AhrensNCELPXSec")
32 {
33 
34 }
AhrensNCELPXSec::AhrensNCELPXSec ( string  config)

Definition at line 36 of file AhrensNCELPXSec.cxx.

36  :
37 XSecAlgorithmI("genie::AhrensNCELPXSec", config)
38 {
39 
40 }
AhrensNCELPXSec::~AhrensNCELPXSec ( )
virtual

Definition at line 42 of file AhrensNCELPXSec.cxx.

43 {
44 
45 }

Member Function Documentation

void AhrensNCELPXSec::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 142 of file AhrensNCELPXSec.cxx.

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

143 {
144  Algorithm::Configure(config);
145  this->LoadConfig();
146 }
virtual void Configure(const Registry &config)
Definition: Algorithm.cxx:62
void AhrensNCELPXSec::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 148 of file AhrensNCELPXSec.cxx.

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

149 {
150  Algorithm::Configure(config);
151  this->LoadConfig();
152 }
virtual void Configure(const Registry &config)
Definition: Algorithm.cxx:62
double AhrensNCELPXSec::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 130 of file AhrensNCELPXSec.cxx.

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

131 {
132  double xsec = fXSecIntegrator->Integrate(this,interaction);
133  return xsec;
134 }
const XSecIntegratorI * fXSecIntegrator
virtual double Integrate(const XSecAlgorithmI *model, const Interaction *interaction) const =0
void AhrensNCELPXSec::LoadConfig ( void  )
private

Definition at line 154 of file AhrensNCELPXSec.cxx.

References fEta, fFa0, fkAlpha, fkGamma, fMa2, fMuN, fMuP, fMv2, fXSecIntegrator, genie::Algorithm::GetParam(), and genie::Algorithm::SubAlg().

Referenced by Configure().

155 {
156  // alpha and gamma
157  double thw ;
158  GetParam( "WeinbergAngle", thw ) ;
159  double sin2thw = TMath::Power(TMath::Sin(thw), 2);
160  fkAlpha = 1.-2.*sin2thw;
161  fkGamma = -0.66666667*sin2thw;
162 
163  // eta and Fa(q2=0)
164  GetParam( "EL-Axial-Eta", fEta ) ;
165  GetParam( "QEL-FA0", fFa0 ) ;
166 
167  // axial and vector masses
168  double ma, mv ;
169  GetParam( "QEL-Ma", ma ) ;
170  GetParam( "QEL-Mv", mv ) ;
171  fMa2 = TMath::Power(ma,2);
172  fMv2 = TMath::Power(mv,2);
173 
174  // anomalous magnetic moments
175  GetParam( "AnomMagnMoment-P", fMuP ) ;
176  GetParam( "AnomMagnMoment-N", fMuN ) ;
177 
178  // load XSec Integrator
180  dynamic_cast<const XSecIntegratorI *> (this->SubAlg("XSec-Integrator"));
181  assert(fXSecIntegrator);
182 }
Cross Section Integrator Interface.
const XSecIntegratorI * fXSecIntegrator
bool GetParam(const RgKey &name, T &p, bool is_top_call=true) const
const Algorithm * SubAlg(const RgKey &registry_key) const
Definition: Algorithm.cxx:345
bool AhrensNCELPXSec::ValidProcess ( const Interaction i) const
virtual

Can this cross section algorithm handle the input process?

Implements genie::XSecAlgorithmI.

Definition at line 136 of file AhrensNCELPXSec.cxx.

References genie::kISkipProcessChk.

Referenced by XSec().

137 {
138  if(interaction->TestBit(kISkipProcessChk)) return true;
139  return true;
140 }
const UInt_t kISkipProcessChk
if set, skip process validity checks
Definition: Interaction.h:47
double AhrensNCELPXSec::XSec ( const Interaction i,
KinePhaseSpace_t  k 
) const
virtual

Compute the cross section for the input interaction.

Implements genie::XSecAlgorithmI.

Definition at line 47 of file AhrensNCELPXSec.cxx.

References genie::units::A, fEta, fFa0, fkAlpha, fkGamma, fMa2, fMuN, fMuP, fMv2, genie::Target::HitNucMass(), genie::Target::HitNucPdg(), genie::pdg::IsAntiNeutrino(), genie::pdg::IsNeutron(), genie::pdg::IsProton(), genie::utils::mec::J(), genie::utils::kinematics::Jacobian(), genie::constants::kGF2, genie::kIAssumeFreeNucleon, genie::constants::kPi, genie::kPSQ2fE, genie::kRfHitNucRest, LOG, genie::Target::N(), genie::utils::nuclear::NuclQELXSecSuppression(), pDEBUG, genie::InitialState::ProbeE(), genie::InitialState::ProbePdg(), genie::Kinematics::Q2(), genie::utils::kinematics::Q2(), genie::InitialState::Tgt(), genie::XSecAlgorithmI::ValidKinematics(), ValidProcess(), and genie::Target::Z().

49 {
50  if(! this -> ValidProcess (interaction) ) return 0.;
51  if(! this -> ValidKinematics (interaction) ) return 0.;
52 
53  const InitialState & init_state = interaction -> InitState();
54  const Kinematics & kinematics = interaction -> Kine();
55  const Target & target = init_state.Tgt();
56 
57  double E = init_state.ProbeE(kRfHitNucRest);
58  double Q2 = kinematics.Q2();
59  double M = target.HitNucMass();
60  double M2 = TMath::Power(M, 2.);
61  double E2 = TMath::Power(E, 2.);
62  double qmv2 = TMath::Power(1 + Q2/fMv2, 2);
63  double qma2 = TMath::Power(1 + Q2/fMa2, 2);
64 
65  //-- handle terms changing sign for antineutrinos and isospin rotations
66  int nusign = 1;
67  int nucsign = 1;
68  int nupdgc = init_state.ProbePdg();
69  int nucpdgc = target.HitNucPdg();
70  if( pdg::IsAntiNeutrino(nupdgc) ) nusign = -1;
71  if( pdg::IsNeutron(nucpdgc) ) nucsign = -1;
72 
73  //-- compute isoscalar form factor terms
74  double Ge0 = 1.5 * fkGamma / qmv2;
75  double Gm0 = 1.5 * fkGamma * (fMuP+fMuN) / qmv2;
76 
77  //-- compute isovector form factor terms
78  double Ge1 = 0.5 * fkAlpha / qmv2;
79  double Gm1 = 0.5 * fkAlpha * (fMuP-fMuN) / qmv2;
80  double Ga1 = -0.5 * fFa0 * (1 + (nucsign) * fEta) / qma2;
81 
82  //-- compute form factors
83  double Ge = Ge0 + (nucsign) * Ge1;
84  double Gm = Gm0 + (nucsign) * Gm1;
85  double Ga = (nucsign) * Ga1;
86  double Ge2 = TMath::Power(Ge,2);
87  double Gm2 = TMath::Power(Gm,2);
88  double Ga2 = TMath::Power(Ga,2);
89 
90  //-- compute the free nucleon cross section
91  double tau = 0.25 * Q2/M2;
92  double fa = 1-M*tau/E;
93  double fa2 = TMath::Power(fa,2);
94  double fb = tau*(tau+1)*M2/E2;
95  double A = (Ge2/(1+tau)) * (fa2-fb);
96  double B = (Ga2 + tau*Gm2/(1+tau)) * (fa2+fb);
97  double C = 4*tau*(M/E)*Gm*Ga * fa;
98  double xsec0 = 0.5*kGF2/kPi;
99  double xsec = xsec0 * (A + B + (nusign)*C);
100 
101  LOG("AhrensNCEL", pDEBUG)
102  << "dXSec[vN,El]/dQ2 [FreeN](Ev = "<< E<< ", Q2 = "<< Q2 << ") = "<< xsec;
103 
104  //-- The algorithm computes dxsec/dQ2
105  // Check whether variable tranformation is needed
106  if(kps!=kPSQ2fE) {
107  double J = utils::kinematics::Jacobian(interaction,kPSQ2fE,kps);
108  xsec *= J;
109  }
110 
111  //-- if requested return the free nucleon xsec even for input nuclear tgt
112  if( interaction->TestBit(kIAssumeFreeNucleon) ) return xsec;
113 
114  //-- compute nuclear suppression factor
115  // (R(Q2) is adapted from NeuGEN - see comments therein)
116  double R = nuclear::NuclQELXSecSuppression("Default", 0.5, interaction);
117 
118  //-- number of scattering centers in the target
119  int NNucl = (pdg::IsProton(nucpdgc)) ? target.Z() : target.N();
120 
121  LOG("AhrensNCEL", pDEBUG)
122  << "Nuclear suppression factor R(Q2) = " << R << ", NNucl = " << NNucl;
123 
124  //-- compute nuclear cross section
125  xsec *= (R*NNucl);
126 
127  return xsec;
128 }
bool ValidProcess(const Interaction *i) const
Can this cross section algorithm handle the input process?
double J(double q0, double q3, double Enu, double ml)
Definition: MECUtils.cxx:147
double Q2(const Interaction *const i)
Definition: KineUtils.cxx:1077
int HitNucPdg(void) const
Definition: Target.cxx:304
double HitNucMass(void) const
Definition: Target.cxx:233
Generated/set kinematical variables for an event.
Definition: Kinematics.h:39
bool IsNeutron(int pdgc)
Definition: PDGUtils.cxx:341
virtual bool ValidKinematics(const Interaction *i) const
Is the input kinematical point a physically allowed one?
bool IsProton(int pdgc)
Definition: PDGUtils.cxx:336
#define LOG(stream, priority)
A macro that returns the requested log4cpp::Category appending a string (using the FILE...
Definition: Messenger.h:96
static constexpr double A
Definition: Units.h:74
bool IsAntiNeutrino(int pdgc)
Definition: PDGUtils.cxx:118
A Neutrino Interaction Target. Is a transparent encapsulation of quite different physical systems suc...
Definition: Target.h:40
int ProbePdg(void) const
Definition: InitialState.h:64
int Z(void) const
Definition: Target.h:68
int N(void) const
Definition: Target.h:69
const UInt_t kIAssumeFreeNucleon
Definition: Interaction.h:49
double Jacobian(const Interaction *const i, KinePhaseSpace_t f, KinePhaseSpace_t t)
Definition: KineUtils.cxx:130
double Q2(bool selected=false) const
Definition: Kinematics.cxx:125
const Target & Tgt(void) const
Definition: InitialState.h:66
double ProbeE(RefFrame_t rf) const
double NuclQELXSecSuppression(string kftable, double pmax, const Interaction *in)
Initial State information.
Definition: InitialState.h:48
#define pDEBUG
Definition: Messenger.h:63

Member Data Documentation

double genie::AhrensNCELPXSec::fEta
private

Definition at line 56 of file AhrensNCELPXSec.h.

Referenced by LoadConfig(), and XSec().

double genie::AhrensNCELPXSec::fFa0
private

Definition at line 57 of file AhrensNCELPXSec.h.

Referenced by LoadConfig(), and XSec().

double genie::AhrensNCELPXSec::fkAlpha
private

Definition at line 54 of file AhrensNCELPXSec.h.

Referenced by LoadConfig(), and XSec().

double genie::AhrensNCELPXSec::fkGamma
private

Definition at line 55 of file AhrensNCELPXSec.h.

Referenced by LoadConfig(), and XSec().

double genie::AhrensNCELPXSec::fMa2
private

Definition at line 58 of file AhrensNCELPXSec.h.

Referenced by LoadConfig(), and XSec().

double genie::AhrensNCELPXSec::fMuN
private

Definition at line 61 of file AhrensNCELPXSec.h.

Referenced by LoadConfig(), and XSec().

double genie::AhrensNCELPXSec::fMuP
private

Definition at line 60 of file AhrensNCELPXSec.h.

Referenced by LoadConfig(), and XSec().

double genie::AhrensNCELPXSec::fMv2
private

Definition at line 59 of file AhrensNCELPXSec.h.

Referenced by LoadConfig(), and XSec().

const XSecIntegratorI* genie::AhrensNCELPXSec::fXSecIntegrator
private

Definition at line 52 of file AhrensNCELPXSec.h.

Referenced by Integral(), and LoadConfig().


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