Default K40 simulator interface. More...

#include <JK40DefaultSimulatorInterface.hh>

Inheritance diagram for JDETECTOR::JK40DefaultSimulatorInterface:

Classes
struct	JBuffer1D_t
	1D-linear buffer. More...

struct	JBuffer2D_t
	2D-square buffer. More...

Public Member Functions
virtual double	getSinglesRate (const JPMTIdentifier &pmt) const =0
	Get singles rate as a function of PMT. More...

virtual double	getMultiplesRate (const JModuleIdentifier &module, const int M) const =0
	Get multiples rate as a function of optical module. More...

virtual double	getProbability (const double ct) const =0
	Get probability of coincidence. More...

virtual void	generateHits (const JModule &module, const JTimeRange &period, JModuleData &output) const
	Generate hits. More...

Static Public Member Functions
static unsigned int	getRandomIndex (const JBuffer1D_t &buffer, const double random)
	Get index based on random value. More...

static double	getSigma ()
	Get intrinsic time smearing of K40 coincidences. More...

Protected Member Functions
	JK40DefaultSimulatorInterface ()
	Default constructor. More...

Private Attributes
JBuffer2D_t	probability2D
	This correlation matrix is a two-dimensional array in which element [i][j] corresponds to the probability of a genuine coincidence due to K40 decays, where i and j refer to the indices of the PMTs in the optical module. More...

JBuffer1D_t	probability1D
	This probability vector is a one-dimensional array in which element [i] corresponds to the probability of a genuine coincidence due to K40 decays, where i refers to the index of the PMT in the optical module. More...

JBuffer1D_t	probabilityND
	This probability vector is a one-dimensional array in which element [i] corresponds to the probability of an additional hit, where i refers to the index of the PMT in the optical module. More...

JBuffer1D_t	rateL1_Hz
	Multiples rate as a function of the multiplicity. More...

Detailed Description

Default K40 simulator interface.

This class provides for a default implementation of the JK40Simulator interface which is based on a set of virtual methods. These methods constitute a user interface to the K40 background simulation.

Definition at line 35 of file JK40DefaultSimulatorInterface.hh.

Constructor & Destructor Documentation

◆ JK40DefaultSimulatorInterface()

JDETECTOR::JK40DefaultSimulatorInterface::JK40DefaultSimulatorInterface ( )

inlineprotected

Default constructor.

Definition at line 72 of file JK40DefaultSimulatorInterface.hh.

73 {}

Member Function Documentation

◆ getSinglesRate()

virtual double JDETECTOR::JK40DefaultSimulatorInterface::getSinglesRate ( const JPMTIdentifier & pmt ) const

pure virtual

Get singles rate as a function of PMT.

Parameters

pmt	PMT identifier

Returns: rate [Hz]

Implemented in JDETECTOR::JK40DefaultSimulator, and JDETECTOR::JK40RunByRunSimulator.

◆ getMultiplesRate()

virtual double JDETECTOR::JK40DefaultSimulatorInterface::getMultiplesRate	(	const JModuleIdentifier &	module,
		const int	M
	)		const

pure virtual

Get multiples rate as a function of optical module.

Parameters

module	optical module identifier
M	multiplicity (M >= 2)

Returns: rate [Hz]

Implemented in JDETECTOR::JK40DefaultSimulator.

◆ getProbability()

virtual double JDETECTOR::JK40DefaultSimulatorInterface::getProbability ( const double ct ) const

pure virtual

Get probability of coincidence.

Parameters

ct	cosine space angle between PMT axes

Returns: probability

Implemented in JDETECTOR::JK40DefaultSimulator.

◆ generateHits()

virtual void JDETECTOR::JK40DefaultSimulatorInterface::generateHits	(	const JModule &	module,
		const JTimeRange &	period,
		JModuleData &	output
	)		const

inlinevirtual

Generate hits.

Parameters

module	module
period	time window [ns]
output	background data

Implements JDETECTOR::JK40Simulator.

Definition at line 112 of file JK40DefaultSimulatorInterface.hh.

     {
  
       // resize internal buffers
       
       const int N = module.size();
  
       probability2D.resize(N);
       probability1D.resize(N);
       probabilityND.resize(N);
  
       rateL1_Hz.resize(N);
  
       // generate singles
  
       for (int pmt = 0; pmt != N; ++pmt) {
  
         const double rateL0_Hz = getSinglesRate(JPMTIdentifier(module.getID(), pmt));
  
         if (rateL0_Hz > 0.0) {
               
           const double t_ns = 1.0e9 / rateL0_Hz;          // [ns]
               
           for (double t1 = period.getLowerLimit() + gRandom->Exp(t_ns); t1 < period.getUpperLimit(); t1 += gRandom->Exp(t_ns)) {
             output[pmt].push_back(JPMTSignal(t1, 1));
           }
         }
       }
  
       // generate coincidences
  
       double totalRateL1_Hz = 0.0;
  
       for (int i = 0; i != N; ++i) {
         totalRateL1_Hz += rateL1_Hz[i] = getMultiplesRate(module.getID(), i + 2);
       }
  
       if (totalRateL1_Hz > 0.0) {
  
         const double t_ns = 1.0e9 / totalRateL1_Hz;       // [ns]
  
         double t1 = period.getLowerLimit() + gRandom->Exp(t_ns);
  
         if (t1 < period.getUpperLimit()) {
  
           // configure correlation matrix
  
           for (int i = 0; i != N; ++i) {
             
             probability2D[i][i] = 0.0;
  
             for (int j = i + 1; j != N; ++j) {
               
               const double ct = JMATH::getDot(module[i], module[j]);
               const double p  = getProbability(ct);
               
               probability2D[i][j] = p;
               probability2D[j][i] = p;
             }
           }
  
           // determine probability of a coincidence as a function of the PMT number
           
           for (int i = 0; i != N; ++i) {
  
             probability1D[i] = 0.0;
  
             for (int j = 0; j != N; ++j) {
               probability1D[i] += probability2D[i][j];
             }
           }
  
           for ( ; t1 < period.getUpperLimit(); t1 += gRandom->Exp(t_ns)) {
  
             // generate two-fold coincidence
  
             const unsigned int pmt1 = getRandomIndex(probability1D,       gRandom->Rndm());
             const unsigned int pmt2 = getRandomIndex(probability2D[pmt1], gRandom->Rndm());
  
             output[pmt1].insert(JPMTSignal(gRandom->Gaus(t1, getSigma()), 1));
             output[pmt2].insert(JPMTSignal(gRandom->Gaus(t1, getSigma()), 1));
  
             try {
  
               // generate larger than two-fold coincidences, if any
  
               unsigned int M = getRandomIndex(rateL1_Hz, gRandom->Rndm());
  
               if (M != 0) {
  
                 probabilityND = probability2D[pmt1];
  
                 for (unsigned int pmtN = pmt2; M != 0; --M) {
  
                   for (int i = 0; i != N; ++i) {
                     probabilityND[i] *= probability2D[pmtN][i];
                   }
  
                   probabilityND[pmtN] = 0.0;
                   
                   pmtN = getRandomIndex(probabilityND, gRandom->Rndm());
                   
                   output[pmtN].insert(JPMTSignal(gRandom->Gaus(t1, getSigma()), 1));
                 }
               }
             }
             catch (const JNumericalPrecision&) {}
           }
         }
       }
     }

◆ getRandomIndex()

static unsigned int JDETECTOR::JK40DefaultSimulatorInterface::getRandomIndex	(	const JBuffer1D_t &	buffer,
		const double	random
	)

inlinestatic

Get index based on random value.

It is assumed that the values of the input buffer monotonously decrease or increase. This method throws an exception when the summed values in the input buffer is zero.

Parameters

buffer	input values
random	random value <0,1]

Returns: index

Definition at line 244 of file JK40DefaultSimulatorInterface.hh.

     {
       double x = 0.0;
  
       for (JBuffer1D_t::const_iterator i = buffer.begin(); i != buffer.end(); ++i) {
         x += *i;
       }
  
       if (x > 0.0) {
  
         x *= random;
  
         unsigned int index = 0;
  
         for (JBuffer1D_t::const_iterator i = buffer.begin(); i != buffer.end() && (x -= *i) > 0.0; ++i, ++index) {}
  
         if (index == buffer.size()) {
           --index;
         }
  
         return index;
  
       } else {
  
         THROW(JNumericalPrecision, "getRandomIndex(): zero or negative probability.");
       }
     }

◆ getSigma()

static double JDETECTOR::JK40DefaultSimulatorInterface::getSigma ( )

inlinestatic

Get intrinsic time smearing of K40 coincidences.

Returns: sigma [ns]

Definition at line 278 of file JK40DefaultSimulatorInterface.hh.

     {
       return 0.5;
     }

Member Data Documentation

◆ probability2D

JBuffer2D_t JDETECTOR::JK40DefaultSimulatorInterface::probability2D

mutableprivate

This correlation matrix is a two-dimensional array in which element [i][j] corresponds to the probability of a genuine coincidence due to K40 decays, where i and j refer to the indices of the PMTs in the optical module.

Definition at line 289 of file JK40DefaultSimulatorInterface.hh.

◆ probability1D

JBuffer1D_t JDETECTOR::JK40DefaultSimulatorInterface::probability1D

mutableprivate

This probability vector is a one-dimensional array in which element [i] corresponds to the probability of a genuine coincidence due to K40 decays, where i refers to the index of the PMT in the optical module.

Definition at line 296 of file JK40DefaultSimulatorInterface.hh.

◆ probabilityND

JBuffer1D_t JDETECTOR::JK40DefaultSimulatorInterface::probabilityND

mutableprivate

This probability vector is a one-dimensional array in which element [i] corresponds to the probability of an additional hit, where i refers to the index of the PMT in the optical module.

Definition at line 303 of file JK40DefaultSimulatorInterface.hh.

◆ rateL1_Hz

JBuffer1D_t JDETECTOR::JK40DefaultSimulatorInterface::rateL1_Hz

mutableprivate

Multiples rate as a function of the multiplicity.

The index i corresponds to multiplicity M = i + 2.

Definition at line 309 of file JK40DefaultSimulatorInterface.hh.

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

JK40DefaultSimulatorInterface.hh

Classes

Public Member Functions

Static Public Member Functions

Protected Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ JK40DefaultSimulatorInterface()

Member Function Documentation

◆ getSinglesRate()

◆ getMultiplesRate()

◆ getProbability()

◆ generateHits()

◆ getRandomIndex()

◆ getSigma()

Member Data Documentation

◆ probability2D

◆ probability1D

◆ probabilityND

◆ rateL1_Hz