// silicon strips //
// //
//////////////////////////////////////////////////////
-const Float_t AliITSsegmentationSSD::fgkDxDefault = 72960.;
+const Float_t AliITSsegmentationSSD::fgkDxDefault = 73000.;
const Float_t AliITSsegmentationSSD::fgkDzDefault = 40000.;
const Float_t AliITSsegmentationSSD::fgkDyDefault = 300.;
const Float_t AliITSsegmentationSSD::fgkPitchDefault = 95.;
const Int_t AliITSsegmentationSSD::fgkNstripsDefault = 768;
+const Int_t AliITSsegmentationSSD::fgkNchipsPerSide = 6;
+const Int_t AliITSsegmentationSSD::fgkNstripsPerChip = 128;
ClassImp(AliITSsegmentationSSD)
+
AliITSsegmentationSSD::AliITSsegmentationSSD(Option_t *opt): AliITSsegmentation(),
fNstrips(0),
fStereoP(0),
fStereoN(0),
fPitch(0),
-fStereoPl5(0),
-fStereoNl5(0),
-fStereoPl6(0),
-fStereoNl6(0),
fLayer(0){
// default constructor
- SetDetSize(fgkDxDefault,fgkDzDefault,fgkDyDefault);
- SetPadSize(fgkPitchDefault,0.);
- SetNPads(fgkNstripsDefault,0);
- SetAngles();
+ SetDetSize(fgkDxDefault,fgkDzDefault,fgkDyDefault);
+ SetPadSize(fgkPitchDefault,0.);
+ SetNPads(fgkNstripsDefault,0);
+ SetAngles();
if(strstr(opt,"TGeo")){
if(!gGeoManager){
AliError("Geometry is not initialized\n");
}
}
}
-//----------------------------------------------------------------------
-AliITSsegmentationSSD::AliITSsegmentationSSD(AliITSgeom *geom):
-AliITSsegmentation(geom),
-fNstrips(0),
-fStereoP(0),
-fStereoN(0),
-fPitch(0),
-fStereoPl5(0),
-fStereoNl5(0),
-fStereoPl6(0),
-fStereoNl6(0),
-fLayer(0){
- // constuctor
- SetDetSize(fgkDxDefault,fgkDzDefault,fgkDyDefault);
- SetPadSize(fgkPitchDefault,0.);
- SetNPads(fgkNstripsDefault,0);
- SetAngles();
-}
+
//______________________________________________________________________
void AliITSsegmentationSSD::Copy(TObject &obj) const {
// protected method. copy this to obj
((AliITSsegmentationSSD& ) obj).fNstrips = fNstrips;
((AliITSsegmentationSSD& ) obj).fStereoP = fStereoP;
((AliITSsegmentationSSD& ) obj).fStereoN = fStereoN;
- ((AliITSsegmentationSSD& ) obj).fStereoPl5 = fStereoPl5;
- ((AliITSsegmentationSSD& ) obj).fStereoNl5 = fStereoNl5;
- ((AliITSsegmentationSSD& ) obj).fStereoPl6 = fStereoPl6;
- ((AliITSsegmentationSSD& ) obj).fStereoNl6 = fStereoNl6;
((AliITSsegmentationSSD& ) obj).fLayer = fLayer;
((AliITSsegmentationSSD& ) obj).fPitch = fPitch;
((AliITSsegmentationSSD& ) obj).fLayer = fLayer;
fStereoP(0),
fStereoN(0),
fPitch(0),
-fStereoPl5(0),
-fStereoNl5(0),
-fStereoPl6(0),
-fStereoNl6(0),
fLayer(0){
// copy constructor
source.Copy(*this);
//----------------------------------------------------------------------
void AliITSsegmentationSSD::Angles(Float_t &aP,Float_t &aN) const{
// P and N side stereo angles
- if (fLayer == 5){
- aP = fStereoPl5;
- aN = fStereoNl5;
- } // end if
- if (fLayer == 6){
- aP = fStereoPl6;
- aN = fStereoNl6;
- } // end if
+ aP = fStereoP;
+ aN = fStereoN;
}
//----------------------------------------------------------------------
void AliITSsegmentationSSD::SetLayer(Int_t l){
//set fLayer data member (only 5 or 6 are allowed)
if (l==5) fLayer =5;
- if (l==6) fLayer =6;
- if((l!=5) && (l!=6))AliError(Form("Layer can be 5 or 6, not %d",l));
+ else if (l==6) fLayer =6;
+ else AliError(Form("Layer can be 5 or 6, not %d",l));
}
//----------------------------------------------------------------------
void AliITSsegmentationSSD::GetPadTxz(Float_t &x,Float_t &z) const{
Dead region: |000/
|00/
|0/
- // expects x, z in microns
+ // expects x, z in cm
*/
+
+ /*
Float_t stereoP, stereoN;
Angles(stereoP,stereoN);
Float_t tanP = TMath::Tan(stereoP);
z1 += fDz/2;
x = (x1 - z1*tanP)/fPitch;
z = (x1 - tanN*(z1 - fDz))/fPitch;
+ */
+
+ Float_t P=0;
+ Float_t N=0;
+ if(fLayer==5) {
+ P = 105.26*x - 0.7895*z + 382.000; //- 0.79*z + 381.89;
+ N = P + 3.684*z - 4;
+ }
+ else if(fLayer==6) {
+ P = -105.26*x - 0.7895*z + 385.000; //- 0.79*z + 384.66;
+ N = P + 3.684*z + 4;
+ }
+ else AliError("Layer can be 5 or 6");
+
+ x=P;
+ z=N;
+
}
//----------------------------------------------------------------------
void AliITSsegmentationSSD::GetPadIxz(Float_t x,Float_t z,Int_t &iP,Int_t &iN) const {
// returns P and N sided strip numbers for a given location.
- /* _- Z
- + angle / ^
- fNstrips v | N-Side ...0
- \-------/------------|-----------\--------\
- |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\|
- |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\|
- |00\\/////////////...|..\\\\\\\\\\\\\\\\\\|
- X <--|000/////////////... |...\\\\\\\\\\\\\\\\\|
- |00/////////////... | ...\\\\\\\\\\\\\\\\|
- |0/////////////... | ...\\\\\\\\\\\\\\\|
- |//////////////... | ...\\\\\\\\\\\\\\\|
- /-----\--------------|--------------------/
- fNstrips-1 P-Side ...0
- |0\
- |00\
- Dead region: |000/
- |00/
- |0/
-
- // expects x, z in microns
- */
-
- Float_t stereoP, stereoN;
- Angles(stereoP,stereoN);
- Float_t tanP=TMath::Tan(stereoP);
- Float_t tanN=TMath::Tan(stereoN);
- Float_t x1=x,z1=z;
- x1 += fDx/2;
- z1 += fDz/2;
- Float_t ldX = x1 - z1*tanP; // distance from left-down edge
- iP = (Int_t)(ldX/fPitch);
- iP = (iP<0)? -1: iP;
- iP = (iP>fNstrips)? -1: iP;
-
- ldX = x1 - tanN*(fDz - z1);
- iN = (Int_t)(ldX/fPitch);
- iN = (iN<0)? -1: iN;
- iN = (iN>fNstrips)? -1: iN;
+ // expects x, z in cm
+ GetPadTxz(x,z);
+ iP = Int_t(x+0.5);
+ iN = Int_t(z+0.5);
}
//-------------------------------------------------------
-void AliITSsegmentationSSD::GetPadCxz(Int_t iP,Int_t iN,Float_t &x,Float_t &z) const {
+void AliITSsegmentationSSD::GetPadCxz(Float_t iP,Float_t iN,Float_t &x,Float_t &z) const {
// actually this is the GetCrossing(Float_t &,Float_t &)
- // returns local x, z in microns !
-
- Float_t lDx = fDx; // detector size in x direction, microns
- Float_t lDz = fDz; // detector size in z direction, microns
- Float_t xP; // x coordinate in the P side from the first P strip
- Float_t xN; // x coordinate in the N side from the first N strip
- Float_t stereoP, stereoN;
- Angles(stereoP,stereoN);
- Float_t kP=TMath::Tan(stereoP);
- Float_t kN=TMath::Tan(stereoN);
+ // returns local x, z in cm
+ const Float_t kStartXzero=3.64325;
+ const Float_t kDeltaXzero5or6=0.02239;
+ const Float_t kDeltaZ5to6=7.6/7.0;
- xP=iP*fPitch;
- xN=iN*fPitch;
- x = xP + kP*(lDz*kN-xP+xN)/(kP+kN);
- z = (lDz*kN-xP+xN)/(kP+kN);
- x -= lDx/2;
- z -= lDz/2;
- //if(TMath::Abs(z) > Dz/2) cout<<"Warning, wrong z local ="<<z<<endl;
- // Check that zL is inside the detector for the
- // correspondent xP and xN coordinates
+ z = 1.9*(iN-iP)/7.0;
+ x = kStartXzero-(285*iN + 1045*iP)/140000.0;
- return;
+ if (fLayer==5){
+ z += kDeltaZ5to6;
+ x = -x + kDeltaXzero5or6;
+ }
+ else if (fLayer==6) {
+ z -= kDeltaZ5to6;
+ x += kDeltaXzero5or6;
+ }
+ else {
+ AliWarning("Layer shoudl be 5 or 6");
+ x = -99999;
+ z = -99999;
+ }
}
//______________________________________________________________________
Bool_t AliITSsegmentationSSD::LocalToDet(Float_t x,Float_t z,
|00/
|0/
*/
- const Double_t kconst = 1.0E-04; // convert microns to cm.
-
- x /= kconst; // convert to microns
- z /= kconst; // convert to microns
- this->GetPadTxz(x,z);
-
- // first for P side
- iP = (Int_t) x;
- if(iP<0 || iP>=fNstrips) iP=-1; // strip number must be in range.
- // Now for N side)
- iN = (Int_t) z;
- if(iN<0 || iN>=fNstrips) iN=-1; // strip number must be in range.
- return kTRUE;
+ Float_t dx,dz;
+ const Double_t kconst = 1.0E-04; // convert microns to cm.
+ dx = 0.5*kconst*Dx();
+ dz = 0.5*kconst*Dz();
+ if( (x<-dx) || (x>dx) ) {
+ iP=-1;
+ AliWarning(Form("Input argument %f out of range (%f, %f)",x,dx,-dx));
+ return kFALSE; // outside of defined volume.
+ } // outside x range.
+ if( (z<-dz) || (z>dz) ) {
+ iN=-1;
+ AliWarning(Form("Input argument %f out of range (%f, %f)",z,dz,-dz));
+ return kFALSE; // outside of defined volume.
+ }
+
+ //x /= kconst; // convert to microns
+ //z /= kconst; // convert to microns
+ this->GetPadTxz(x,z);
+
+ // first for P side
+ iP = (Int_t) x;
+ if(iP<0 || iP>=fNstrips) iP=-1; // strip number must be in range.
+ // Now for N side)
+ iN = (Int_t) z;
+ if(iN<0 || iN>=fNstrips) iN=-1; // strip number must be in range.
+ return kTRUE;
}
//----------------------------------------------------------------------
void AliITSsegmentationSSD::DetToLocal(Int_t ix,Int_t iPN,
// x = a + b + z*tan(fStereoP); a = Dpx(iP)*(iP+0.5)-dx; b = dz*th;
// for strips n-side
// x = a + b + z*tan(fStereoP); a = Dpx(iN)*(iN+0.5)-dx; b = -dz*th;
+ AliWarning("This function has not been verified. Should probably use GetPadCxz");
const Double_t kconst = 1.0E-04; // convert microns to cm.
Float_t flag=kconst*Dx(); // error value
Double_t th=0.0,dx,dz,i,a,b=0.0,xb[4],zb[4];
return;
}
//----------------------------------------------------------------------
-Bool_t AliITSsegmentationSSD::GetCrossing(Int_t iP,Int_t iN,
- Float_t &x,Float_t &z,
- Float_t c[2][2]){
- // Given one P side strip and one N side strip, Returns kTRUE if they
- // cross each other and the location of the two crossing strips and
- // their correxlation matrix c[2][2].
- /* _- Z
- + angle / ^
- fNstrips v | N-Side ...0
- \-------/------------|-----------\--------\
- |\\\\\\/////////////.|\\\\\\\\\\\\\\\\\\\\|
- |0\\\\/////////////..|.\\\\\\\\\\\\\\\\\\\|
- |00\\/////////////...|..\\\\\\\\\\\\\\\\\\|
- X <--|000/////////////... |...\\\\\\\\\\\\\\\\\|
- |00/////////////... | ...\\\\\\\\\\\\\\\\|
- |0/////////////... | ...\\\\\\\\\\\\\\\|
- |//////////////... | ...\\\\\\\\\\\\\\\|
- /-----\--------------|--------------------/
- fNstrips-1 P-Side ...0
- |0\
- |00\
- Dead region: |000/
- |00/
- |0/
- c[2][2] is defined as follows
- /c[0][0] c[0][1]\ /delta iP\ = /delta x\
- \c[1][0] c[1][1]/ \delta iN/ = \delta z/
- */
- const Double_t kconst = 1.0E-04; // convert microns to cm.
- Double_t thp,thn,th,dx,dz,p,ip,in;
- Float_t stereoP, stereoN;
- Angles(stereoP,stereoN);
-
- thp = TMath::Tan(stereoP);
- thn = TMath::Tan(-stereoN);
- th = thp-thn;
- if(th==0.0) { // parall strips then never cross.
- x = 0.0;
- z = 0.0;
- c[0][0] = c[1][0] = c[0][1] = c[1][1] = 0.0;
- return kFALSE;
- } // end if
- // The strips must cross some place in space.
- ip = (Double_t) iP; // convert to double now for speed
- in = (Double_t) iN; // convert to double now for speed
- dx = 0.5*kconst*Dx(); // half distance in x in cm
- dz = 0.5*kconst*Dz(); // half distance in z in cm
- p = kconst*Dpx(iP); // Get strip spacing/pitch now
- x = 0.5*p+dx + (p*(in*thp-ip*thn)-2.0*dz*thp*thn)/th;
- z =(p*(in-ip)-dz*(thp+thn))/th;
- // compute correlations.
- c[0][0] = -thn*p/th; // dx/diP
- c[1][1] = p/th; // dz/diN
- c[0][1] = p*thp/th; // dx/diN
- c[1][0] = -p/th; // dz/diP
- if(x<-dx || x>dx || z<-dz || z>dz) return kFALSE; // crossing is outside
- // of the detector so
- // these strips don't
- // cross.
- return kTRUE;
+Int_t AliITSsegmentationSSD::GetChipFromChannel(Int_t ix, Int_t iz) const {
+ // returns chip number (in range 0-11) starting from channel number
+
+ if( (iz>=fgkNstripsDefault) || (iz<0) || (ix<0) || (ix>1) ) {
+ AliError("Bad cell number");
+ return -1;
+ }
+
+ if(ix==1) iz = 1535-iz;
+ Int_t theChip =iz/fgkNstripsPerChip;
+ return theChip;
+
+}
+//----------------------------------------------------------------------
+Int_t AliITSsegmentationSSD::GetChipFromLocal(Float_t xloc, Float_t zloc) const
+{
+ // returns chip numbers starting from local coordinates
+ // The two Nside chip number and Pside chip number are
+ // coded as chip=Nchip*10+Pchip
+
+ Int_t iP=0;
+ Int_t iN=0;
+ if (!LocalToDet(xloc,zloc,iP,iN) ||
+ (iP<0) || (iP>=fNstrips) || (iN<0) || (iN>=fNstrips) ) {
+ //AliWarning("Bad local coordinate");
+ return -1;
+ }
+
+ Int_t iChip = GetChipFromChannel(0,iP);
+ iChip += 10*GetChipFromChannel(1,iN); // add Nside
+
+ return iChip;
+
+}
+//
+
+Int_t AliITSsegmentationSSD::GetChipsInLocalWindow(Int_t* array, Float_t zmin, Float_t zmax,
+ Float_t xmin, Float_t xmax) const {
+
+ Int_t nChipInW = 0;
+
+ Float_t zminDet=-fDz*1.0E-04/2.;
+ Float_t zmaxDet=fDz*1.0E-04/2.;
+ if(zmin<zminDet) zmin=zminDet;
+ if(zmax>zmaxDet) zmax=zmaxDet;
+
+ Float_t xminDet=-fDx*1.0E-04/2;
+ Float_t xmaxDet=fDx*1.0E-04/2;
+ if(xmin<xminDet) xmin=xminDet;
+ if(xmax>xmaxDet) xmax=xmaxDet;
+
+ Int_t n1N=-1;
+ Int_t n1P=-1;
+ Int_t n1=GetChipFromLocal(xmin,zmin);
+ if(n1!=-1) { // Note! Recpoint can be on the sensor but in the dead area not covered by strips!
+ n1N = (Int_t) (n1/10); // N-side chip coded as 10*chip_index
+ n1P = n1 - 10 * n1N; // P-side chip coded 0-5
+ array[nChipInW]=n1P;
+ nChipInW++;
+ array[nChipInW]=n1N;
+ nChipInW++;
+ }
+
+ Int_t n2N=-1;
+ Int_t n2P=-1;
+ Int_t n2=GetChipFromLocal(xmin,zmax);
+ if(n2!=-1) { // Note! Recpoint can be on the sensor but in the dead area not covered by strips!
+ n2N = (Int_t) (n2/10); // N-side chip coded as 10*chip_index
+ n2P = n2 - 10 * n2N; // P-side chip coded 0-5
+ if(n2P!=n1P) { array[nChipInW]=n2P; nChipInW++;}
+ if(n2N!=n1N) { array[nChipInW]=n2N; nChipInW++;}
+ }
+
+ Int_t n3N=-1;
+ Int_t n3P=-1;
+ Int_t n3=GetChipFromLocal(xmax,zmin);
+ if(n3!=-1) {
+ n3N=(Int_t) (n3/10); // N-side chip coded as 10*chip_index
+ n3P=n3 - 10 * n3N; // P-side chip coded 0-5
+ if((n3P!=n1P)&&(n3P!=n2P)) { array[nChipInW]=n3P; nChipInW++;}
+ if((n3N!=n1N)&&(n3N!=n2N)) { array[nChipInW]=n3N; nChipInW++;}
+ }
+
+ Int_t n4N=-1;
+ Int_t n4P=-1;
+ Int_t n4=GetChipFromLocal(xmax,zmax);
+ if(n4!=-1) {
+ n4N=(Int_t) (n4/10); // N-side chip coded as 10*chip_index
+ n4P=n4 - 10 * n4N; // P-side chip coded 0-5
+ if((n4P!=n1P)&&(n4P!=n2P)&&(n4P!=n3P)) { array[nChipInW]=n4P; nChipInW++;}
+ if((n4N!=n1N)&&(n4N!=n2N)&&(n4N!=n3N)) { array[nChipInW]=n4N; nChipInW++;}
+ }
+
+ return nChipInW;
+
}
//----------------------------------------------------------------------