ElectronCloudDrifterProcessor.h

#ifndef ELECTRONCLOUDDRIFTERPROCESSOR_H
#define ELECTRONCLOUDDRIFTERPROCESSOR_H 1

// CLHEP
#include <CLHEP/Vector/ThreeVector.h>

// Marlin
#include <marlin/Processor.h>

// GSL
#include <gsl/gsl_errno.h>
#include <gsl/gsl_odeiv.h>

#ifdef MARLIN_USE_AIDA
//Root
#include "TTree.h"
#endif

namespace EVENT {

        class LCRunHeader;
        class LCEvent;
}

namespace marlintpc {

class ElectronCloudDrifterProcessor : public marlin::Processor {

public:
        ElectronCloudDrifterProcessor();

        ~ElectronCloudDrifterProcessor();

        virtual Processor* newProcessor() { return new ElectronCloudDrifterProcessor() ; }

        virtual void init();

        virtual void processRunHeader(lcio::LCRunHeader* run );

        virtual void processEvent(lcio::LCEvent * evt );

        virtual void check(lcio::LCEvent * evt );

        virtual void end();

        static int ion_drift_derivative( double t, const double y[], double f[], void *params );

        static int drift_through_cylinder( double (&)[4], const double min_radius, const double max_radius, const double min_z, const double max_z, const double drift_velocity, const double omega_tau, const bool disable_magnetic_field = false , marlintpc::ElectronCloudDrifterProcessor* processor = 0);

  int _current_cloud;
#ifdef MARLIN_USE_AIDA

  std::vector<TTree*> _tDrift;
#endif

protected:
  struct driftInfo {
    std::vector<double> *position[3];
    std::vector<double> *velocity[3];
    std::vector<double> *Ex;
    std::vector<double> *Ey;
    std::vector<double> *Ez;
    std::vector<double> *Bz;
    std::vector<double> *Br;
  };

        struct DriftParameters {

                double _drift_velocity;
                double _omega_tau;
                double _omega_tau_squared;
                bool   _disable_magnetic_field;
                driftInfo * _info; 
        };


private:

        std::string _input_collection_name;

        std::string _tpc_conditions_collection_name;

        std::string _tpc_section_name;

        bool _primary_drift_section;

        double _omega_tau;

        double _drift_velocity;

        double _longitudinal_diffusion;

        double _transverse_diffusion;

        double _tpc_outer_radius;

        double _tpc_inner_radius;

        double _section_outer_z;

        double _section_inner_z;

        bool _disable_magnetic_field;

        static gsl_odeiv_step *stepper;

        static gsl_odeiv_control *step_control;

        static gsl_odeiv_evolve *evolver;
};

} // namespace marlintpc

#endif // ELECTRONCLOUDDRIFTERPROCESSOR_H