#include <PndDiscSensorGridPhotodetector.h>

Inheritance diagram for SensorGrid::SensorGridPhotodetector:

Classes
struct	PixelTraits

Public Member Functions
	SensorGridPhotodetector (SensorGridBase *sensor_grid_, bool per_pixel_traits_, double const &pde_init, double const &noise_rate_init, double const &time_res_init)

void	SetPixel (int pixel_id, double efficiency, double noise_rate, double time_res_ns)

void	UseInhomogenityFactor (bool flag)

int	Detect (double const &hit_pos_x, double const &hit_pos_y, double const &hit_time_ns, double const &wavelength_nm, PixelInfo &pixel_info, double &smeared_time_ns) const
	Handle photon detection: More...

void	GenerateNoise (double const &time_start_ns, double const &time_window_ns, std::vector< std::pair< int, double > > &hits) const
	Generate noise hits. More...

virtual double	GetPDE (const double &) const
	Derived classes should override this function and return the average pde of the sensor. More...

virtual double	GetInhomegenityFactor (double const &, double const &) const
	Derived classes should override this function to account for spatial PDE deviations (e.g. due to gain inhomgenity) More...

double	GetSmearedTime (double const &time_value, PixelInfo const &pixel_info) const
	Apply time smearing. More...

int	GenerateNoise (double const &time_start_ns, double const &time_window_ns)
	Reinit noise iterator and return number of noise hits. More...

bool	GetNoiseHit (int &pixel_number, double &hit_time_ns, double &smeared_time_ns)
	Noise hit generator function which has to be called after GenerateNoise() to retrieve the noise hits. More...

void	SetDCR (double const &dcr_Hz)
	Set the dark count rate for all pixels to dcr_Hz. More...

const SensorGridBase *	GetGrid ()

Protected Member Functions
	SensorGridPhotodetector ()

virtual	~SensorGridPhotodetector ()

void	Init (SensorGridBase *sensor_grid_, bool per_pixel_traits_, double const &efficiency_init, double const &noise_rate_init, double const &time_res_init)
	Initialization - can also be used in derived class ctors (avoid code duplication). More...

Protected Attributes
bool	per_pixel_traits

bool	use_inhomogenity_factor

PixelTraits *	pixel_traits

SensorGridBase *	sensor_grid

int	noisegen_pixel_number

double	noisegen_time_start_ns

double	noisegen_time_window_ns

int	noisegen_n_hits

int	noisegen_current_hit

double	noisegen_current_time_sigma

Detailed Description

Definition at line 20 of file PndDiscSensorGridPhotodetector.h.

Constructor & Destructor Documentation

SensorGrid::SensorGridPhotodetector::SensorGridPhotodetector	(	SensorGridBase *	sensor_grid_,
		bool	per_pixel_traits_,
		double const &	pde_init,
		double const &	noise_rate_init,
		double const &	time_res_init
	)

Definition at line 26 of file PndDiscSensorGridPhotodetector.cxx.

References Init().

     :  per_pixel_traits(per_pixel_traits_), use_inhomogenity_factor(false),sensor_grid(sensor_grid_)
 {
     Init(sensor_grid_, per_pixel_traits_, efficiency_init, noise_rate_init, time_res_init);
 }

SensorGrid::SensorGridPhotodetector::SensorGridPhotodetector ( )

inlineprotected

Definition at line 28 of file PndDiscSensorGridPhotodetector.h.

28 {}; // for use in derived classes

virtual SensorGrid::SensorGridPhotodetector::~SensorGridPhotodetector ( )

inlineprotectedvirtual

Definition at line 29 of file PndDiscSensorGridPhotodetector.h.

29 {};

Member Function Documentation

int SensorGrid::SensorGridPhotodetector::Detect	(	double const &	hit_pos_x,
		double const &	hit_pos_y,
		double const &	hit_time_ns,
		double const &	wavelength_nm,
		PixelInfo &	pixel_info,
		double &	smeared_time_ns
	)		const

Handle photon detection:

Detection of a hit.

Definition at line 62 of file PndDiscSensorGridPhotodetector.cxx.

References SensorGrid::PixelInfo::column_on_grid, SensorGrid::SensorGridPhotodetector::PixelTraits::efficiency, GetInhomegenityFactor(), GetPDE(), SensorGrid::PixelInfo::grid_id, per_pixel_traits, SensorGrid::PixelInfo::pixel_number, pixel_traits, SensorGrid::SensorGridBase::PositionToPixel(), SensorGrid::PixelInfo::row_on_grid, sensor_grid, SensorGrid::SensorGridPhotodetector::PixelTraits::time_res_ns, and use_inhomogenity_factor.

Referenced by PndDiscTaskDigitization::Exec().

                                                                                                                                                                                                         {
 #ifdef DETECT_DEBUG
     ofs_detect_debug << "X: " << hit_pos_x << " Y: " << hit_pos_y ;
 #endif
     if(!sensor_grid->PositionToPixel(hit_pos_x, hit_pos_y, pixel_info)) {
 #ifdef DETECT_DEBUG
                         ofs_detect_debug << " not detected\n";
 #endif
                         return -1; // no pixel (geometric efficiency)
     }
 #ifdef DETECT_DEBUG
     ofs_detect_debug << "Pixel: " << pixel_info.pixel_number << " Grid: " << pixel_info.grid_id << " Column/row: " << pixel_info.column_on_grid << " / " << pixel_info.row_on_grid << std::endl;
 #endif
 
     double global_pde = GetPDE(wavelength_nm);
     if(use_inhomogenity_factor) global_pde*=GetInhomegenityFactor(hit_pos_x, hit_pos_y);
 
     if(per_pixel_traits) {
         if(gRandom->Uniform() > pixel_traits[pixel_info.pixel_number].efficiency*global_pde) return -1; // global PDE and per pixel efficiency (e.g. due to bad gain uniformity)
         smeared_time_ns = gRandom->Gaus(hit_time_ns, pixel_traits[pixel_info.pixel_number].time_res_ns);
     } else {
         if(gRandom->Uniform() > pixel_traits->efficiency*global_pde) return -1;
         smeared_time_ns = gRandom->Gaus(hit_time_ns, pixel_traits->time_res_ns);
     }
     return pixel_info.pixel_number;
 }

void SensorGrid::SensorGridPhotodetector::GenerateNoise	(	double const &	time_start_ns,
		double const &	time_window_ns,
		std::vector< std::pair< int, double > > &	hits
	)		const

Generate noise hits.

Generate noise on the sensor.

Definition at line 91 of file PndDiscSensorGridPhotodetector.cxx.

References SensorGrid::SensorGridBase::GetNumberOfPixels(), hit, hits, i, SensorGrid::SensorGridPhotodetector::PixelTraits::noise_rate, per_pixel_traits, pixel_traits, and sensor_grid.

                                                                                                                                                       {
     int i, n_hits, n_pixels = sensor_grid->GetNumberOfPixels();
     double avg_n_hits;
     std::pair<int, double> hit;
 
     // loop over all pixel numbers
     for(hit.first = 0; hit.first < n_pixels; ++hit.first) {
         // average number of noise events per pixel:
         if(per_pixel_traits)
             avg_n_hits = pixel_traits[hit.first].noise_rate*time_window_ns*1E-9;
         else
             avg_n_hits = pixel_traits->noise_rate*time_window_ns*1E-9;
 
         n_hits = gRandom->Poisson(avg_n_hits); // compute number of hits on this pixel
         // generate the hits in the given time window:
         for(i=0; i<n_hits; ++i) {
             hit.second = time_start_ns + gRandom->Uniform(time_window_ns); // distribute hit times in window
             hits.push_back(hit); // append hits to vector
         }
     }
 }

int SensorGrid::SensorGridPhotodetector::GenerateNoise	(	double const &	time_start_ns,
		double const &	time_window_ns
	)

Reinit noise iterator and return number of noise hits.

Definition at line 115 of file PndDiscSensorGridPhotodetector.cxx.

References noisegen_current_hit, noisegen_n_hits, noisegen_pixel_number, noisegen_time_start_ns, and noisegen_time_window_ns.

                                                                                                       {
     noisegen_pixel_number   = -1;
     noisegen_n_hits         = 0;
     noisegen_current_hit    = 0;
     noisegen_time_start_ns  = time_start_ns;
     noisegen_time_window_ns = time_window_ns;
 
     return noisegen_n_hits;
 }

const SensorGridBase* SensorGrid::SensorGridPhotodetector::GetGrid ( )

inline

Definition at line 71 of file PndDiscSensorGridPhotodetector.h.

References sensor_grid.

Referenced by PndDiscTaskDigitization::Exec().

71 {return sensor_grid;}

SensorGrid::SensorGridPhotodetector::sensor_grid

SensorGridBase * sensor_grid

Definition: PndDiscSensorGridPhotodetector.h:77

virtual double SensorGrid::SensorGridPhotodetector::GetInhomegenityFactor	(	double const &	,
		double const &
	)		const

inlinevirtual

Derived classes should override this function to account for spatial PDE deviations (e.g. due to gain inhomgenity)

This function is used to implement inhomogenitites over the whole sensor, which cannot be treated as single pixel efficiencies, e.g. if the pixels are large compared to the spatial deviation of the inhomogenity.

Definition at line 56 of file PndDiscSensorGridPhotodetector.h.

Referenced by Detect().

56 {return 1.0;} //FIXME//hit_pos_x hit_pos_y//[R.K.03/2017] unused variable(s)

bool SensorGrid::SensorGridPhotodetector::GetNoiseHit	(	int &	pixel_number,
		double &	hit_time_ns,
		double &	smeared_time_ns
	)

Noise hit generator function which has to be called after GenerateNoise() to retrieve the noise hits.

Definition at line 127 of file PndDiscSensorGridPhotodetector.cxx.

References SensorGrid::SensorGridBase::GetNumberOfPixels(), SensorGrid::SensorGridPhotodetector::PixelTraits::noise_rate, noisegen_current_hit, noisegen_current_time_sigma, noisegen_n_hits, noisegen_pixel_number, noisegen_time_start_ns, noisegen_time_window_ns, per_pixel_traits, pixel_traits, sensor_grid, and SensorGrid::SensorGridPhotodetector::PixelTraits::time_res_ns.

                                                                                                             {
     if(noisegen_pixel_number >= sensor_grid->GetNumberOfPixels()) return false;
 
     // after iterating over all hits, switch to next pixel.
     if(noisegen_current_hit >= noisegen_n_hits) {
         do{
             // next pixel:
             noisegen_pixel_number++;
             if(noisegen_pixel_number >= sensor_grid->GetNumberOfPixels()) return false;
 
             // average number of noise events on this pixel:
             double avg_n_hits = 0.0;
             if(per_pixel_traits) {
                 avg_n_hits = pixel_traits[pixel_number].noise_rate*noisegen_time_window_ns*1E-9;
                 noisegen_current_time_sigma = pixel_traits[pixel_number].time_res_ns;
             }
             else {
                 avg_n_hits = pixel_traits->noise_rate*noisegen_time_window_ns*1E-9;
                 noisegen_current_time_sigma = pixel_traits->time_res_ns;
             }
 
             // number of hits on this pixel:
             noisegen_n_hits = gRandom->Poisson(avg_n_hits); // compute number of hits on this pixel
         }
         while(noisegen_n_hits == 0);
 
         noisegen_current_hit = 0;
         LOG(INFO) << Form("Number of generated hits on pixel %d are: %d\n", noisegen_pixel_number, noisegen_n_hits);
     }
 
     pixel_number = noisegen_pixel_number;
     hit_time_ns  = noisegen_time_start_ns + gRandom->Uniform(noisegen_time_window_ns); // distribute hit times in window
     smeared_time_ns = gRandom->Gaus(hit_time_ns, noisegen_current_time_sigma);
     noisegen_current_hit++;
 
     return true;
 }

virtual double SensorGrid::SensorGridPhotodetector::GetPDE ( const double & ) const

inlinevirtual

Derived classes should override this function and return the average pde of the sensor.

Per pixel deviations of the PDE can be taken into account by including them in a individual pixel efficiency.

Reimplemented in DiscDIRC_Photodetector.

Definition at line 48 of file PndDiscSensorGridPhotodetector.h.

Referenced by Detect().

48 {return 1.0;} //FIXME // wavelength_nm //[R.K.03/2017] unused variable(s)

double SensorGrid::SensorGridPhotodetector::GetSmearedTime	(	double const &	hit_time_ns,
		PixelInfo const &	pixel_info
	)		const

Apply time smearing.

Can be used to smear the time of noise entries. Noise is returned with its true time stamp for dead-time handling and an additional smeared time would increase the array, so it appears to me that it is more handy to smear afterwards. A better way might be a noise iterator which generates one hit at a time (-> implemented, will be tested).

Definition at line 171 of file PndDiscSensorGridPhotodetector.cxx.

References per_pixel_traits, SensorGrid::PixelInfo::pixel_number, pixel_traits, and SensorGrid::SensorGridPhotodetector::PixelTraits::time_res_ns.

                                                                                                              {
     double smeared_time_ns;
     if(per_pixel_traits) {
         smeared_time_ns = gRandom->Gaus(hit_time_ns, pixel_traits[pixel_info.pixel_number].time_res_ns);
     } else {
         smeared_time_ns = gRandom->Gaus(hit_time_ns, pixel_traits->time_res_ns);
     }
     return smeared_time_ns;
 }

void SensorGrid::SensorGridPhotodetector::Init	(	SensorGridBase *	sensor_grid_,
		bool	per_pixel_traits_,
		double const &	efficiency_init,
		double const &	noise_rate_init,
		double const &	time_res_init
	)

protected

Initialization - can also be used in derived class ctors (avoid code duplication).

Definition at line 34 of file PndDiscSensorGridPhotodetector.cxx.

References SensorGrid::SensorGridPhotodetector::PixelTraits::efficiency, SensorGrid::SensorGridBase::GetNumberOfPixels(), i, SensorGrid::SensorGridBase::LockGrid(), SensorGrid::SensorGridPhotodetector::PixelTraits::noise_rate, per_pixel_traits, pixel_traits, sensor_grid, and SensorGrid::SensorGridPhotodetector::PixelTraits::time_res_ns.

Referenced by DiscDIRC_Photodetector::Init(), and SensorGridPhotodetector().

                                                                                                                                                                                      {
     sensor_grid = sensor_grid_;
     sensor_grid->LockGrid(true);
     per_pixel_traits = per_pixel_traits_;
     if(per_pixel_traits) {
         pixel_traits = new PixelTraits[sensor_grid->GetNumberOfPixels()];
         //if(pixel_traits == NULL)
         //    throw ...
         for(int i = 0; i< sensor_grid->GetNumberOfPixels(); ++i) {
             pixel_traits[i].efficiency  = efficiency_init;
             pixel_traits[i].noise_rate  = noise_rate_init;
             pixel_traits[i].time_res_ns = time_res_init;
         }
     } else {
         pixel_traits = new PixelTraits();
         pixel_traits->efficiency  = efficiency_init;
         pixel_traits->noise_rate  = noise_rate_init;
         pixel_traits->time_res_ns = time_res_init;
     }
 }

void SensorGrid::SensorGridPhotodetector::SetDCR ( double const & dcr_Hz )

Set the dark count rate for all pixels to dcr_Hz.

Will set the DCR for all pixels to dcr_Hz. The current implementation does not provide the functionality to model statistical fluctuations in the DCR.

Definition at line 185 of file PndDiscSensorGridPhotodetector.cxx.

References SensorGrid::SensorGridBase::GetNumberOfPixels(), i, SensorGrid::SensorGridPhotodetector::PixelTraits::noise_rate, per_pixel_traits, pixel_traits, and sensor_grid.

                                                           {
     if(per_pixel_traits) {
         int n_pixels = sensor_grid->GetNumberOfPixels();
         for(int i=0; i<n_pixels; ++i) {
             pixel_traits[i].noise_rate = dcr_Hz;
         }
     }
     else
         pixel_traits->noise_rate = dcr_Hz;
 }