1 //-----------------------------------------------------//
4 // Date : August 05 2003 //
6 // Utility code for ALICE-PMD //
8 //-----------------------------------------------------//
10 #include "AliPMDUtility.h"
14 ClassImp(AliPMDUtility)
16 AliPMDUtility::AliPMDUtility()
26 AliPMDUtility::AliPMDUtility(Float_t Px, Float_t Py, Float_t Pz)
36 AliPMDUtility::~AliPMDUtility()
40 void AliPMDUtility::HexGeomCellPos(Int_t ism, Int_t xpad, Int_t ypad, Float_t &xpos, Float_t &ypos)
46 // Supermodeule number starting from 0
49 This converts PMD cluster or CELL coordinates
50 to Global coordinates.
51 Written by Prof. S.C. Phatak
55 Float_t celldia = 0.5;
56 const Float_t pi = 3.14159;
57 const double sqrth=0.8660254; // sqrth = sqrt(3.)/2.
59 ism --> supermodule no ( 0 - 26 )
60 idet --> detector ( pmd or cpv : not required now )
61 j --> xpad ( goes from 1 to 72 )
62 k --> ypad ( goes from 1 to 72 )
63 xp --> global x coordinate
64 yp --> global y coordinate
66 (xp0,yp0) corner positions of all supermodules in global
67 coordinate system. That is the origin
68 of the local ( supermodule ) coordinate system.
73 -17.9084, 18.2166, 54.3416, -35.9709, 0.154144,
74 36.2791, -54.0334, -17.9084, 18.2166, 36.7791,
75 18.7166, 0.654194, 72.9041, 54.8416, 36.7792,
76 109.029, 90.9666, 72.9042, -18.8708, -36.9334,
77 -54.996, -36.9332, -54.9958, -73.0584, -54.9956,
83 -32.1395, -32.1395, -32.1395, -63.4247, -63.4247,
84 -63.4247, -94.7098, -94.7098, -94.7098, 0.545689,
85 31.8309, 63.1161, 0.545632, 31.8308, 63.116,
86 0.545573, 31.8308, 63.116, 31.5737, 0.288616,
87 -30.9965, 62.859, 31.5738, 0.288733, 94.1442,
92 angles of rotation for three sets of supermodules
93 The angle is same for first nine, next nine and last nine
97 Float_t th[3] = {0., -2.*pi/3., 2.*pi/3.};
98 Float_t xr, yr, xinit, yinit, cs, sn;
101 xinit and yinit are coordinates of the cell in local coordinate system
104 xinit = (j)*celldia+(k)/2.*celldia;
105 yinit = sqrth*(k)/2.;
112 xr=cs*xinit+sn*yinit;
113 yr=-sn*xinit+cs*yinit;
122 void AliPMDUtility::RectGeomCellPos(Int_t ism, Int_t ium, Int_t xpad, Int_t ypad, Float_t &xpos, Float_t &ypos)
124 // This routine finds the cell eta,phi for the new PMD rectangular
126 // Authors : Bedanga Mohanty and Dipak Mishra - 29.4.2003
127 // modified by B. K. Nnadi for change of coordinate sys
129 // SMA ---> Supermodule Type A ( SM - 0)
130 // SMAR ---> Supermodule Type A ROTATED ( SM - 1)
131 // SMB ---> Supermodule Type B ( SM - 2)
132 // SMBR ---> Supermodule Type B ROTATED ( SM - 3)
134 // ism : number of supermodules in one plane = 4
135 // ium : number of unitmodules in one SM = 6
136 // gb_um : (global) unit module numbering in a supermodule
139 Int_t gb_um = ism*6 + ium;
143 // Corner positions (x,y) of the 24 unit moudles in ALICE PMD
147 85.15, 60.85, 36.55, 85.15, 60.85, 36.55, //SMA
148 -85.15, -60.85, -36.55, -85.15, -60.85, -36.55, //SMAR
149 84.90, 36.60, 84.90, 36.60, 84.90, 36.60, //SMB
150 -84.90, -36.60, -84.90, -36.60, -84.90, -36.60 //SMBR
155 32.45708755, 32.45708755, 32.45708755, //SMA
156 -9.30645245, -9.30645245, -9.30645245, //SMA
157 -32.45708755, -32.45708755, -32.45708755, //SMAR
158 9.30645245, 9.30645245, 9.30645245, //SMAR
159 -31.63540818, -31.63540818, -52.61435544, //SMB
160 -52.61435544, -73.59330270, -73.59330270, //SMB
161 31.63540818, 31.63540818, 52.61435544, //SMBR
162 52.61435544, 73.59330270, 73.59330270 //SMBR
165 const Float_t root_3 = 1.73205; // sqrt(3.);
166 const Float_t cell_radius = 0.25;
169 //Every even row of cells is shifted and placed
170 //in geant so this condition
181 if(ism == 0 || ism == 2)
183 ypos = ycorner[gb_um] +
184 irow*cell_radius*root_3;
186 xpos = xcorner[gb_um] -
187 icol*2.0*cell_radius - shift;
189 else if(ism == 1 || ism == 3)
191 ypos = ycorner[gb_um] -
192 irow*cell_radius*root_3;
194 xpos = xcorner[gb_um] +
195 icol*2.0*cell_radius + shift;
199 void AliPMDUtility::SetPxPyPz(Float_t Px, Float_t Py, Float_t Pz)
206 void AliPMDUtility::SetXYZ(Float_t xPos, Float_t yPos, Float_t zPos)
212 void AliPMDUtility::CalculateEta()
214 Float_t rpxpy, theta, eta;
216 rpxpy = TMath::Sqrt(fPx*fPx + fPy*fPy);
217 theta = TMath::ATan2(rpxpy,fPz);
218 eta = -TMath::Log(TMath::Tan(0.5*theta));
222 void AliPMDUtility::CalculatePhi()
224 Float_t pybypx, phi = 0., phi1;
229 if(fPy<0) phi = 270.;
234 if(pybypx < 0) pybypx = - pybypx;
235 phi1 = TMath::ATan(pybypx)*180./3.14159;
237 if(fPx > 0 && fPy > 0) phi = phi1; // 1st Quadrant
238 if(fPx < 0 && fPy > 0) phi = 180 - phi1; // 2nd Quadrant
239 if(fPx < 0 && fPy < 0) phi = 180 + phi1; // 3rd Quadrant
240 if(fPx > 0 && fPy < 0) phi = 360 - phi1; // 4th Quadrant
243 phi = phi*3.14159/180.;
248 void AliPMDUtility::CalculateEtaPhi()
250 Float_t rpxpy, theta, eta;
251 Float_t pybypx, phi = 0., phi1;
253 rpxpy = TMath::Sqrt(fPx*fPx + fPy*fPy);
254 theta = TMath::ATan2(rpxpy,fPz);
255 eta = -TMath::Log(TMath::Tan(0.5*theta));
260 if(fPy<0) phi = 270.;
265 if(pybypx < 0) pybypx = - pybypx;
266 phi1 = TMath::ATan(pybypx)*180./3.14159;
267 if(fPx > 0 && fPy > 0) phi = phi1; // 1st Quadrant
268 if(fPx < 0 && fPy > 0) phi = 180 - phi1; // 2nd Quadrant
269 if(fPx < 0 && fPy < 0) phi = 180 + phi1; // 3rd Quadrant
270 if(fPx > 0 && fPy < 0) phi = 360 - phi1; // 4th Quadrant
273 phi = phi*3.14159/180.;
279 Float_t AliPMDUtility::GetTheta() const
283 Float_t AliPMDUtility::GetEta() const
287 Float_t AliPMDUtility::GetPhi() const