1 ///////////////////////////////////////////////////////////////////////////////
3 // Inner Traking System version 0 //
7 <img src="picts/AliITSv0Class.gif">
10 <font size=+2 color=red>
11 <p>The responsible person for this module is
12 <a href="mailto:roberto.barbera@ct.infn.it">Roberto Barbera</a>.
18 ///////////////////////////////////////////////////////////////////////////////
31 //_____________________________________________________________________________
32 AliITSv0::AliITSv0() : AliITS()
35 // Default constructor for ITS
39 //_____________________________________________________________________________
40 AliITSv0::AliITSv0(const char *name, const char *title)
44 // Standard constructor for ITS
48 //_____________________________________________________________________________
49 void AliITSv0::CreateGeometry()
52 // Create Geometry for ITS version 0
56 <img src="picts/AliITSv0Tree.gif">
61 <img src="picts/AliITSv0.gif">
65 AliMC* pMC = AliMC::GetMC();
67 Float_t rl[6] = { 3.9,7.6,14.,24.,40.,45. }; //SILICON LAYERS INNER RADIUS
68 Float_t drl[6] = { .755,.755,.809,.809,.7,.7 }; //THICKNESS OF LAYERS (in % radiation length)
69 Float_t dzl[6] = { 12.67,16.91,20.85,29.15,45.11,50.975 }; //HALF LENGTH OF LAYERS
70 Float_t drpcb[6] = { 0.,0.,.06,.06,0.,0. }; //PCB THICKNESS
71 Float_t drcu[6] = { 0.,0.,.0504,.0504,.0357,.0357 }; //COPPER THICKNESS
72 Float_t drsi[6] = { 0.,0.,.006,.006,.3571,.3571 }; //SILICON THICKNESS
73 Float_t drcer[6] = { 0.,0.,.08,.08,0.,0. }; //CERAMICS THICKNESS
74 Float_t drepx[6] = { 0.,0.,0.,0.,.5357,.5357 }; //EPOXY THICKNESS
75 Float_t drpla[6] = { 0.,0.,0.,0.,.1786,.1786 }; //PLASTIC THICKNESS
76 Float_t dzb[6] = { 0.,0.,15.,15.,4.,4. }; //LENGTH OF BOXES
77 Float_t dphi[6] = { 72.,72.,72.,72.,50.6,45. }; //COVERED PHI-RANGE FOR LAYERS 1-6
82 Float_t rend, drca_tpc, dzco, zend, dits[3], rlim, drsu, zmax;
83 Float_t zpos, dzco1, dzco2;
84 Float_t drcac[6], acone, dphii;
85 Float_t pcits[15], xltpc;
86 Float_t rstep, r0, z0, acable, fp, dz, zi, ri;
91 Int_t *idtmed = gAlice->Idtmed();
93 // CONVERT INTO CM (RL(SI)=9.36 CM)
94 for (i = 0; i < 6; ++i) {
95 drl[i] = drl[i]/100. * 9.36;
98 // SUPPORT ENDPLANE THICKNESS
99 drsu = 2.*0.06 + 1./20; // 1./20. is 1 cm of honeycomb (1/20 carbon density)
101 // CABLE THICKNESS (HORIZONTAL CABLES CONNECTING THE LAYERS)
112 // CABLE THICKNESS (CONICAL CABLES CONNECTING THE LAYERS)
120 // CONE RADIUS AT 1ST LAYER
124 // FIELD CAGE HALF LENGTH
132 // PARAMETERS FOR SMALL (1/2) ITS
140 // DRCA_TPC=DRCA_TPC/2.
147 // EQUAL DISTRIBUTION INTO THE 6 LAYERS
148 rstep = drca_tpc / 6.;
149 for (i = 0; i < 6; ++i) {
150 drcac[i] = (i+1) * rstep;
153 // NUMBER OF PHI SECTORS
157 // NOW PACK USING THICKNESS
159 for (i = 0; i < 6; ++i) {
164 // PHI-PACKING NOT SUFFICIENT ?
166 if (dphi[i]/45 < fp) {
167 drcac[i] = drcac[i]*fp*45/dphi[i];
172 // --- Define ghost volume containing the six layers and fill it with air
177 pMC->Gsvolu("ITSV", "TUBE", idtmed[275], dgh, 3);
179 // --- Place the ghost volume in its mother volume (ALIC) and make it
182 pMC->Gspos("ITSV", 1, "ALIC", 0., 0., 0., 0, "ONLY");
183 pMC->Gsatt("ITSV", "SEEN", 0);
185 // ITS LAYERS (SILICON)
188 dits[1] = rl[0] + drl[0];
190 pMC->Gsvolu("ITS1", "TUBE", idtmed[199], dits, 3);
191 pMC->Gspos("ITS1", 1, "ITSV", 0., 0., 0., 0, "ONLY");
194 dits[1] = rl[1] + drl[1];
196 pMC->Gsvolu("ITS2", "TUBE", idtmed[199], dits, 3);
197 pMC->Gspos("ITS2", 1, "ITSV", 0., 0., 0., 0, "ONLY");
200 dits[1] = rl[2] + drl[2];
202 pMC->Gsvolu("ITS3", "TUBE", idtmed[224], dits, 3);
203 pMC->Gspos("ITS3", 1, "ITSV", 0., 0., 0., 0, "ONLY");
206 dits[1] = rl[3] + drl[3];
208 pMC->Gsvolu("ITS4", "TUBE", idtmed[224], dits, 3);
209 pMC->Gspos("ITS4", 1, "ITSV", 0., 0., 0., 0, "ONLY");
212 dits[1] = rl[4] + drl[4];
214 pMC->Gsvolu("ITS5", "TUBE", idtmed[249], dits, 3);
215 pMC->Gspos("ITS5", 1, "ITSV", 0., 0., 0., 0, "ONLY");
218 dits[1] = rl[5] + drl[5];
220 pMC->Gsvolu("ITS6", "TUBE", idtmed[249], dits, 3);
221 pMC->Gspos("ITS6", 1, "ITSV", 0., 0., 0., 0, "ONLY");
224 // PCB (layer #3 and #4)
226 pMC->Gsvolu("IPCB", "TUBE", idtmed[233], dits, 0);
227 for (i = 2; i < 4; ++i) {
229 dits[1] = dits[0] + drpcb[i];
230 dits[2] = dzb[i] / 2.;
231 zpos = dzl[i] + dits[2];
232 pMC->Gsposp("IPCB", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
233 pMC->Gsposp("IPCB", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
236 // COPPER (layer #3 and #4)
238 pMC->Gsvolu("ICO2", "TUBE", idtmed[234], dits, 0);
239 for (i = 2; i < 4; ++i) {
240 dits[0] = rl[i] + drpcb[i];
241 dits[1] = dits[0] + drcu[i];
242 dits[2] = dzb[i] / 2.;
243 zpos = dzl[i] + dits[2];
244 pMC->Gsposp("ICO2", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
245 pMC->Gsposp("ICO2", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
248 // CERAMICS (layer #3 and #4)
250 pMC->Gsvolu("ICER", "TUBE", idtmed[235], dits, 0);
251 for (i = 2; i < 4; ++i) {
252 dits[0] = rl[i] + drpcb[i] + drcu[i];
253 dits[1] = dits[0] + drcer[i];
254 dits[2] = dzb[i] / 2.;
255 zpos = dzl[i] + dits[2];
256 pMC->Gsposp("ICER", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
257 pMC->Gsposp("ICER", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
260 // SILICON (layer #3 and #4)
262 pMC->Gsvolu("ISI2", "TUBE", idtmed[226], dits, 0);
263 for (i = 2; i < 4; ++i) {
264 dits[0] = rl[i] + drpcb[i] + drcu[i] + drcer[i];
265 dits[1] = dits[0] + drsi[i];
266 dits[2] = dzb[i] / 2.;
267 zpos = dzl[i - 1] + dits[2];
268 pMC->Gsposp("ISI2", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
269 pMC->Gsposp("ISI2", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
272 // PLASTIC (G10FR4) (layer #5 and #6)
274 pMC->Gsvolu("IPLA", "TUBE", idtmed[262], dits, 0);
275 for (i = 4; i < 6; ++i) {
277 dits[1] = dits[0] + drpla[i];
278 dits[2] = dzb[i] / 2.;
279 zpos = dzl[i] + dits[2];
280 pMC->Gsposp("IPLA", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
281 pMC->Gsposp("IPLA", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
284 // COPPER (layer #5 and #6)
286 pMC->Gsvolu("ICO3", "TUBE", idtmed[259], dits, 0);
287 for (i = 4; i < 6; ++i) {
288 dits[0] = rl[i] + drpla[i];
289 dits[1] = dits[0] + drcu[i];
290 dits[2] = dzb[i] / 2.;
291 zpos = dzl[i] + dits[2];
292 pMC->Gsposp("ICO3", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
293 pMC->Gsposp("ICO3", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
296 // EPOXY (layer #5 and #6)
298 pMC->Gsvolu("IEPX", "TUBE", idtmed[262], dits, 0);
299 for (i = 4; i < 6; ++i) {
300 dits[0] = rl[i] + drpla[i] + drcu[i];
301 dits[1] = dits[0] + drepx[i];
302 dits[2] = dzb[i] / 2.;
303 zpos = dzl[i] + dits[2];
304 pMC->Gsposp("IEPX", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
305 pMC->Gsposp("IEPX", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
308 // SILICON (layer #5 and #6)
310 pMC->Gsvolu("ISI3", "TUBE", idtmed[251], dits, 0);
311 for (i = 4; i < 6; ++i) {
312 dits[0] = rl[i] + drpla[i] + drcu[i] + drepx[i];
313 dits[1] = dits[0] + drsi[i];
314 dits[2] = dzb[i] / 2.;
315 zpos = dzl[i] + dits[2];
316 pMC->Gsposp("ISI3", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
317 pMC->Gsposp("ISI3", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
322 pMC->Gsvolu("ISUP", "TUBE", idtmed[274], dits, 0);
323 for (i = 0; i < 6; ++i) {
325 if (i < 5) dits[1] = rl[i+1];
328 zpos = dzl[i] + dzb[i] + dits[2];
329 pMC->Gsposp("ISUP", i+1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
330 pMC->Gsposp("ISUP", i+7, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
333 // CABLES (HORIZONTAL)
335 pMC->Gsvolu("ICHO", "TUBE", idtmed[278], dits, 0);
336 for (i = 0; i < 6; ++i) {
338 dits[1] = dits[0] + drca;
339 dits[2] = (rzcone + TMath::Tan(acone) * (rl[i] - rl[0]) - (dzl[i]+ dzb[i] + drsu)) / 2.;
340 zpos = dzl[i] + dzb[i] + drsu + dits[2];
341 pMC->Gsposp("ICHO", i+1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
342 pMC->Gsposp("ICHO", i+7, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
344 // DEFINE A CONICAL GHOST VOLUME FOR THE PHI SEGMENTATION
351 pcits[6] = pcits[3] + TMath::Tan(acone) * (rlim - rl[0]);
352 pcits[7] = rlim - rl[0] + 3.5;
354 pMC->Gsvolu("ICMO", "PCON", idtmed[275], pcits, 9);
355 AliMatrix(idrotm[200], 90., 0., 90., 90., 180., 0.);
356 pMC->Gspos("ICMO", 1, "ITSV", 0., 0., 0., 0, "ONLY");
357 pMC->Gspos("ICMO", 2, "ITSV", 0., 0., 0., idrotm[200], "ONLY");
359 // DIVIDE INTO NSEC PHI-SECTIONS
361 pMC->Gsdvn("ICMD", "ICMO", nsec, 2);
362 pMC->Gsatt("ICMO", "SEEN", 0);
363 pMC->Gsatt("ICMD", "SEEN", 0);
368 pMC->Gsvolu("ICCO", "PCON", idtmed[278], pcits, 0);
369 for (i = 1; i < 6; ++i) {
370 pcits[0] = -dphi[i] / 2.;
373 dzco = TMath::Tan(acone) * (rl[i] - rl[i-1]);
375 dzco1 = zmax - (rzcone + TMath::Tan(acone) * (rl[5] - rl[0])) -2.;
376 dzco2 = (rlim - rl[5]) * TMath::Tan(acone);
377 if (rl[5] + dzco1 / TMath::Tan(acone) < rlim) {
383 pcits[3] = rzcone + TMath::Tan(acone) * (rl[i] - rl[0]);
384 pcits[4] = rl[i] - drcac[i] / TMath::Sin(acone);
386 pcits[6] = pcits[3] + dzco;
387 pcits[7] = rl[i] + dzco / TMath::Tan(acone) - drcac[i] / TMath::Sin(acone);
388 pcits[8] = rl[i] + dzco / TMath::Tan(acone);
390 pMC->Gsposp("ICCO", i, "ICMD", 0., 0., 0., 0, "ONLY", pcits, 9);
396 // CONICAL CABLES BELOW TPC
398 // DEFINE A CONICAL GHOST VOLUME FOR THE PHI SEGMENTATION
404 pcits[4] = pcits[5] - drca_tpc;
406 pcits[8] = pcits[4] + (pcits[6] - pcits[3]) * TMath::Tan(acable * kDegrad);
407 pcits[7] = pcits[8] - drca_tpc;
408 AliMatrix(idrotm[200], 90., 0., 90., 90., 180., 0.);
409 pMC->Gsvolu("ICCM", "PCON", idtmed[275], pcits, 9);
410 pMC->Gspos("ICCM", 1, "ALIC", 0., 0., 0., 0, "ONLY");
411 pMC->Gspos("ICCM", 2, "ALIC", 0., 0., 0., idrotm[200], "ONLY");
412 pMC->Gsdvn("ITMD", "ICCM", nsec, 2);
413 pMC->Gsatt("ITMD", "SEEN", 0);
414 pMC->Gsatt("ICCM", "SEEN", 0);
416 // NOW PLACE SEGMENTS WITH DECREASING PHI SEGMENTS INTO THE
420 pMC->Gsvolu("ITTT", "PCON", idtmed[278], pcits, 0);
423 dz = (xltpc - zend) / 9.;
424 for (i = 0; i < 9; ++i) {
425 zi = z0 + i* dz + dz / 2.;
426 ri = r0 + (zi - z0) * TMath::Tan(acable * kDegrad);
427 dphii = dphi[5] * r0 / ri;
428 pcits[0] = -dphii / 2.;
430 pcits[3] = zi - dz / 2.;
431 pcits[5] = r0 + (pcits[3] - z0) * TMath::Tan(acable * kDegrad);
432 pcits[4] = pcits[5] - drca_tpc;
433 pcits[6] = zi + dz / 2.;
434 pcits[8] = r0 + (pcits[6] - z0) * TMath::Tan(acable * kDegrad);
435 pcits[7] = pcits[8] - drca_tpc;
437 pMC->Gsposp("ITTT", i+1, "ITMD", 0., 0., 0., 0, "ONLY", pcits, 9);
440 // --- Outputs the geometry tree in the EUCLID/CAD format
443 pMC->WriteEuclid("ITSgeometry", "ITSV", 1, 5);
447 //_____________________________________________________________________________
448 void AliITSv0::DrawModule()
451 // Draw a shaded view of the FMD version 1
454 AliMC* pMC = AliMC::GetMC();
456 // Set everything unseen
457 pMC->Gsatt("*", "seen", -1);
459 // Set ALIC mother visible
460 pMC->Gsatt("ALIC","SEEN",0);
462 // Set the volumes visible
463 pMC->Gsatt("ITSV","SEEN",0);
464 pMC->Gsatt("ITS1","SEEN",1);
465 pMC->Gsatt("ITS2","SEEN",1);
466 pMC->Gsatt("ITS3","SEEN",1);
467 pMC->Gsatt("ITS4","SEEN",1);
468 pMC->Gsatt("ITS5","SEEN",1);
469 pMC->Gsatt("ITS6","SEEN",1);
470 pMC->Gsatt("ISI2","SEEN",1);
471 pMC->Gsatt("IPLA","SEEN",1);
472 pMC->Gsatt("ICHO","SEEN",1);
473 pMC->Gsatt("ICMO","SEEN",0);
474 pMC->Gsatt("ICMD","SEEN",0);
475 pMC->Gsatt("ICCO","SEEN",1);
476 pMC->Gsatt("ICCM","SEEN",0);
477 pMC->Gsatt("ITMD","SEEN",0);
478 pMC->Gsatt("ITTT","SEEN",1);
480 pMC->Gdopt("hide", "on");
481 pMC->Gdopt("shad", "on");
482 pMC->Gsatt("*", "fill", 7);
483 pMC->SetClipBox(".");
484 pMC->SetClipBox("*", 0, 300, -300, 300, -300, 300);
486 pMC->Gdraw("alic", 40, 30, 0, 11, 10, .05, .05);
487 pMC->Gdhead(1111, "Inner Tracking System Version 0");
488 pMC->Gdman(16, 6, "MAN");
491 //_____________________________________________________________________________
492 void AliITSv0::StepManager()
495 // Called at every step in the ITS
502 TClonesArray &lhits = *fHits;
503 AliMC* pMC = AliMC::GetMC();
505 if(pMC->TrackCharge() && pMC->Edep()) {
507 // Only entering charged tracks
508 if((id=pMC->CurrentVol(0,copy))==fIdSens1) {
510 id=pMC->CurrentVolOff(1,0,copy);
512 id=pMC->CurrentVolOff(2,0,copy);
514 } else if(id==fIdSens2) {
516 id=pMC->CurrentVolOff(1,0,copy);
518 id=pMC->CurrentVolOff(2,0,copy);
520 } else if(id==fIdSens3) {
523 id=pMC->CurrentVolOff(1,0,copy);
525 } else if(id==fIdSens4) {
528 id=pMC->CurrentVolOff(1,0,copy);
530 } else if(id==fIdSens5) {
533 id=pMC->CurrentVolOff(1,0,copy);
535 } else if(id==fIdSens6) {
538 id=pMC->CurrentVolOff(1,0,copy);
541 pMC->TrackPosition(position);
542 pMC->TrackMomentum(momentum);
546 hits[3]=momentum[0]*momentum[3];
547 hits[4]=momentum[1]*momentum[3];
548 hits[5]=momentum[2]*momentum[3];
550 new(lhits[fNhits++]) AliITShit(fIshunt,gAlice->CurrentTrack(),vol,hits);