#include <HPDIonFeedbackSim.h>

Inheritance diagram for HPDIonFeedbackSim:

Public Member Functions
void	addThermalNoise (CaloSamples &samples, CLHEP::HepRandomEngine *)

virtual double	correctPE (const DetId &detId, double npe, CLHEP::HepRandomEngine *) const

double	getIonFeedback (DetId detId, double signal, double pedWidth, bool doThermal, bool isInGeV, CLHEP::HepRandomEngine *)

	HPDIonFeedbackSim (const edm::ParameterSet &, const CaloShapes *shapes)
	need a shaper in order to set thermal noise More...

void	setDbService (const HcalDbService *service)

	~HPDIonFeedbackSim ()

Private Member Functions
double	fCtoGeV (const DetId &detId) const

Private Attributes
const HcalDbService *	theDbService

const CaloShapes *	theShapes

Detailed Description

Definition at line 27 of file HPDIonFeedbackSim.h.

Constructor & Destructor Documentation

HPDIonFeedbackSim::HPDIonFeedbackSim	(	const edm::ParameterSet &	iConfig,
		const CaloShapes *	shapes
	)

need a shaper in order to set thermal noise

Definition at line 32 of file HPDIonFeedbackSim.cc.

 : theDbService(0), theShapes(shapes)
 {
 }

HPDIonFeedbackSim::~HPDIonFeedbackSim ( )

Definition at line 37 of file HPDIonFeedbackSim.cc.

38 {

39 }

Member Function Documentation

void HPDIonFeedbackSim::addThermalNoise	(	CaloSamples &	samples,
		CLHEP::HepRandomEngine *	engine
	)

Definition at line 104 of file HPDIonFeedbackSim.cc.

References correctPE(), i, CaloSamples::id(), j, CaloShapes::shape(), CaloSamples::size(), and theShapes.

Referenced by HcalAmplifier::amplify().

 {
   // make some chance to add a PE (with a chance of feedback)
   // for each time sample
   double meanPE = 0.02;
   DetId detId(samples.id());
   int nSamples = samples.size();
   const CaloVShape * shape = theShapes->shape(detId);
   for(int i = 0; i < nSamples; ++i) 
   {
     CLHEP::RandPoissonQ theRandPoissonQ(*engine, meanPE);
     double npe = theRandPoissonQ.fire();
     // TODOprobably should time-smear these
     if(npe > 0.)
     {
       // chance of feedback
       npe = correctPE(detId, npe, engine);
       for(int j = i; j < nSamples; ++j)
       {
         double timeFromPE = (j-i) * 25.;
         samples[j] += (*shape)(timeFromPE) * npe;
       }
     }
   }
 }

double HPDIonFeedbackSim::correctPE	(	const DetId &	detId,
		double	npe,
		CLHEP::HepRandomEngine *	engine
	)		const

virtual

Implements CaloVPECorrection.

Definition at line 67 of file HPDIonFeedbackSim.cc.

References j, max(), p4, and pe2Charge.

Referenced by addThermalNoise(), and getIonFeedback().

 {
     double rateInTail = 0.000211988;//read this from XML file
     double rateInSecondTail = 4.61579e-06;//read this from XML file
 
     // three gauss fit is applied to data to get ion feedback distribution
     // parameters (in fC)
     // first gaussian
     // double p0 = 9.53192e+05;
     // double p1 = -3.13653e-01;
     // double p2 = 2.78350e+00;
 
     // second gaussian
     // double p3 = 2.41611e+03;
     double p4 = 2.06117e+01;
     double p5 = 1.09239e+01;
 
     // third gaussian
     // double p6 = 3.42793e+01;
     double p7 = 5.45548e+01;
     double p8 = 1.59696e+01;
 
     double noise = 0.;          // fC
     int nFirst  = (int)(CLHEP::RandBinomial::shoot(engine, npe, rateInTail));
     int nSecond = (int)(CLHEP::RandBinomial::shoot(engine, npe, rateInSecondTail));
 
     for (int j = 0; j < nFirst; ++j) {
       noise += CLHEP::RandGaussQ::shoot(engine, p4, p5);
     }
     for (int j = 0; j < nSecond; ++j) {
       noise += CLHEP::RandGaussQ::shoot(engine, p7, p8);
     }
 
     return npe + std::max(noise/pe2Charge, 0.);
 }

double HPDIonFeedbackSim::fCtoGeV ( const DetId & detId ) const

private

Definition at line 131 of file HPDIonFeedbackSim.cc.

References HcalDbService::getGain(), HcalDbService::getGainWidth(), HcalGain::getValue(), query::result, and theDbService.

Referenced by getIonFeedback().

 {
   assert(theDbService != 0);
   HcalGenericDetId hcalGenDetId(detId);
   const HcalGain* gains = theDbService->getGain(hcalGenDetId);
   const HcalGainWidth* gwidths = theDbService->getGainWidth(hcalGenDetId);
   if (!gains || !gwidths )
   {
     edm::LogError("HcalAmplifier") << "Could not fetch HCAL conditions for channel " << hcalGenDetId;
   }
   // only one gain will be recorded per channel, so just use capID 0 for now
   double result = gains->getValue(0);
   return result;
 }

double HPDIonFeedbackSim::getIonFeedback	(	DetId	detId,
		double	signal,
		double	pedWidth,
		bool	doThermal,
		bool	isInGeV,
		CLHEP::HepRandomEngine *	engine
	)

Definition at line 41 of file HPDIonFeedbackSim.cc.

References DeDxDiscriminatorTools::charge(), correctPE(), fCtoGeV(), and pe2Charge.

 {
     
   //    HcalDetId id = detId; 
     
     double GeVperfC = 1.;
     if(isInGeV) GeVperfC = 1./fCtoGeV(detId);
     
     double charge = signal / GeVperfC;
     
     double noise = 0.;          // fC
     if (charge > 3. * pedWidth) {    // 3 sigma away from pedestal mean
         int npe = int (charge / pe2Charge);
         if(doThermal) {
           double electronEmission = 0.08;
           CLHEP::RandPoissonQ theRandPoissonQ(*engine, electronEmission);
           npe += theRandPoissonQ.fire();
         }
 
         noise = correctPE(detId, npe, engine) - npe;
     }
     return (noise * GeVperfC);
 
 }