/*
$Log$
+Revision 1.5 2003/08/13 17:37:29 hristov
+Bug fix (Alpha)
+
+Revision 1.4 2003/08/05 16:14:20 morsch
+Some problems with too big fluctuations corrected. (A. de Falco)
+
+Revision 1.1 2003/01/06 10:13:09 morsch
+First commit.
+
*/
+// Implementation of AliFastResponse for the Muon Spectrometer resolution.
+// The response depends on the charge of the muon and
+// the background level.
+// The class uses the instance of an object of type AliMUONFastTracking to
+// obtain the smearing parameters.
+// Author: andreas.morsch@cern.ch
+
#include "AliFastMuonTrackingRes.h"
#include "AliMUONFastTracking.h"
#include <TRandom.h>
AliFastMuonTrackingRes::AliFastMuonTrackingRes() :
AliFastResponse("Resolution", "Muon Tracking Resolution")
{
+// Deafault constructor
SetBackground();
}
void AliFastMuonTrackingRes::Init()
{
+// Initialisation
fFastTracking = AliMUONFastTracking::Instance();
fFastTracking->Init(fBackground);
}
void AliFastMuonTrackingRes::Evaluate(Float_t p, Float_t theta , Float_t phi,
Float_t& pS, Float_t& thetaS, Float_t& phiS)
{
+//
+// Evaluate Gaussian smearing from given kinematics
+//
Double_t meanp = fFastTracking->MeanP (p, theta, phi, Int_t(fCharge));
Double_t sigmap = fFastTracking->SigmaP (p, theta, phi, Int_t(fCharge));
Double_t sigmag2 = fFastTracking->SigmaG2(p, theta, phi, Int_t(fCharge));
Int_t ip,itheta,iphi;
- TF1* fitp = fFastTracking->GetFitP();
-
fFastTracking->GetIpIthetaIphi(p, theta, phi, Int_t(fCharge), ip, itheta, iphi);
- if (sigmap == 0) {
- printf ("WARNING!!! sigmap=0: ");
- printf ("ip= %d itheta = %d iphi = %d ", ip, itheta, iphi);
- printf ("p= %f theta = %f phi = %f\n", p, theta, phi);
+ TF1* fitp = fFastTracking->GetFitP(ip,itheta,iphi);
+
+ Float_t curmeanp = fitp->GetParameter(0);
+ Float_t cursigmap = fitp->GetParameter(1);
+ Float_t cursigma1p = fitp->GetParameter(2);
+ Float_t curnormg2 = fitp->GetParameter(3);
+ Float_t curmeang2 = fitp->GetParameter(4);
+ Float_t cursigmag2 = fitp->GetParameter(5);
+ if (curmeanp != meanp || cursigmap != sigmap || cursigma1p != sigma1p ||
+ curnormg2 != normg2 || curmeang2 != meang2 || cursigmag2 != sigmag2){
+ printf ("Setting new parameters for ip=%d itheta=%d iphi=%d\n",ip,itheta,iphi);
+ fitp->SetParameters(meanp,sigmap,sigma1p,normg2,meang2,sigmag2);
}
-
- fitp->SetParameters(meanp,sigmap,sigma1p,normg2,meang2,sigmag2);
Double_t meantheta = fFastTracking->MeanTheta (p, theta, phi, Int_t(fCharge));
Double_t sigmatheta = fFastTracking->SigmaTheta(p, theta, phi, Int_t(fCharge));
Double_t meanphi = fFastTracking->MeanPhi (p, theta, phi, Int_t(fCharge));
Double_t sigmaphi = fFastTracking->SigmaPhi (p, theta, phi, Int_t(fCharge));
-
+
+ if (sigmatheta<0 || sigmaphi<0)
+ printf ("bin %d %d %d sigmatheta = %f, sigmaphi = %f\n",
+ ip,itheta,iphi,sigmatheta,sigmaphi);
// Components different from ip=0 have the RMS bigger than mean
Float_t ptp[3] = { 1.219576,-0.354764,-0.690117 };
Float_t ptph[3] = { 0.977522, 0.016269, 0.023158 };
Float_t pphp[3] = { 1.303256,-0.464847,-0.869322 };
// Smeared momentum
- pS = p + fitp->GetRandom();
- Float_t dp = pS - p;
-
+ pS = -1.;
+ // Float_t dpmax = 5. + ip * 2.5;
+ // Float_t dpmax = 5. + ip * 2;
+ Float_t dpmax;
+ if (sigmag2<999.) dpmax = 5. * (sigmap + sigmag2);
+ else dpmax = 5. * sigmap;
+ Float_t dp = 100;
+ while (pS<0 || TMath::Abs(dp)>dpmax) {
+ pS = p + fitp->GetRandom();
+ dp = pS - p;
+ }
// Smeared phi
+ Float_t sigmaphiold=sigmaphi;
if (ip==0) sigmaphi *= pphp[0] + pphp[1] * dp + pphp[2] * dp*dp;
+ if (sigmaphi<0.5 * sigmaphiold) sigmaphi = 0.5 * sigmaphiold;
+ if (sigmaphi>2. * sigmaphiold) sigmaphi = 2. * sigmaphiold;
phiS = phi + gRandom->Gaus(meanphi, sigmaphi);
Float_t dphi = phiS - phi;
// Smeared theta
+ Float_t sigmathetaold=sigmatheta;
if (ip==0) sigmatheta *= ptp[0] + ptp[1] * dp + ptp[2] * dp*dp;
if (ip==0) sigmatheta *= ptph[0] + ptph[1] * dphi + ptph[2] * dphi*dphi;
+ if (sigmatheta<0.5 * sigmathetaold) sigmatheta = 0.5 * sigmathetaold;
+ if (sigmatheta>2. * sigmathetaold) sigmatheta = 2. * sigmathetaold;
thetaS = theta + gRandom->Gaus(meantheta,sigmatheta);
}