1 ///////////////////////////////////////////////////////////////////////////////
3 // Inner Traking System version 1 //
7 <img src="picts/AliITSv1Class.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 AliITSv1::AliITSv1() : AliITS()
35 // Default constructor for the ITS
39 //_____________________________________________________________________________
40 AliITSv1::AliITSv1(const char *name, const char *title)
44 // Standard constructor for the ITS
48 //_____________________________________________________________________________
49 void AliITSv1::CreateGeometry()
52 // Create geometry for version 1 of the ITS
55 // Create Geometry for ITS version 0
59 <img src="picts/AliITSv1Tree.gif">
64 <img src="picts/AliITSv1.gif">
69 AliMC* pMC = AliMC::GetMC();
71 Float_t drcer[6] = { 0.,0.,.08,.08,0.,0. }; //CERAMICS THICKNESS
72 Float_t drepx[6] = { 0.,0.,0.,0.,.5357,.5357 }; //EPOXY THICKNESS
73 Float_t drpla[6] = { 0.,0.,0.,0.,.1786,.1786 }; //PLASTIC THICKNESS
74 Float_t dzb[6] = { 0.,0.,15.,15.,4.,4. }; //LENGTH OF BOXES
75 Float_t dphi[6] = { 72.,72.,72.,72.,50.6,45. }; //COVERED PHI-RANGE FOR LAYERS 1-6
76 Float_t rl[6] = { 3.9,7.6,14.,24.,40.,45. }; //SILICON LAYERS INNER RADIUS
77 Float_t drl[6] = { .755,.755,.809,.809,.7,.7 }; //THICKNESS OF LAYERS (in % radiation length)
78 Float_t dzl[6] = { 12.67,16.91,20.85,29.15,45.11,50.975 };//HALF LENGTH OF LAYERS
79 Float_t drpcb[6] = { 0.,0.,.06,.06,0.,0. }; //PCB THICKNESS
80 Float_t drcu[6] = { 0.,0.,.0504,.0504,.0357,.0357 }; //COPPER THICKNESS
81 Float_t drsi[6] = { 0.,0.,.006,.006,.3571,.3571 }; //SILICON THICKNESS
83 Float_t drca = 0, dzfc;
85 Float_t rend, drca_tpc, dzco, zend, dits[3], rlim, drsu, zmax;
86 Float_t zpos, dzco1, dzco2;
87 Float_t drcac[6], acone, dphii;
88 Float_t pcits[15], xltpc;
89 Float_t rzcone, rstep, r0, z0, acable, fp, dz, zi, ri;
93 Int_t *idtmed = gAlice->Idtmed();
95 // CONVERT INTO CM (RL(SI)=9.36 CM)
96 for (i = 0; i < 6; ++i) {
97 drl[i] = drl[i] / 100. * 9.36;
100 // SUPPORT ENDPLANE THICKNESS
101 drsu = 2.*0.06+1./20; // 1./20. is 1 cm of honeycomb (1/20 carbon density);
107 // CABLE THICKNESS (CONICAL CABLES CONNECTING THE LAYERS)
115 // CONE RADIUS AT 1ST LAYER
119 // FIELD CAGE HALF LENGTH
127 // PARAMETERS FOR SMALL (1/2) ITS
129 for (i = 0; i < 6; ++i) {
144 // EQUAL DISTRIBUTION INTO THE 6 LAYERS
145 rstep = drca_tpc / 6.;
146 for (i = 0; i < 6; ++i) {
147 drcac[i] = (i+1) * rstep;
150 // NUMBER OF PHI SECTORS
154 // PACK IN PHI AS MUCH AS POSSIBLE
155 // NOW PACK USING THICKNESS
157 for (i = 0; i < 6; ++i) {
162 // PHI-PACKING NOT SUFFICIENT ?
164 if (dphi[i]/45 < fp) {
165 drcac[i] = drcac[i] * fp * 45/dphi[i];
170 // --- Define ghost volume containing the six layers and fill it with air
175 pMC->Gsvolu("ITSV", "TUBE", idtmed[275], dgh, 3);
177 // --- Place the ghost volume in its mother volume (ALIC) and make it
180 pMC->Gspos("ITSV", 1, "ALIC", 0., 0., 0., 0, "ONLY");
181 pMC->Gsatt("ITSV", "SEEN", 0);
183 // ITS LAYERS (SILICON)
186 dits[1] = rl[0] + drl[0];
188 pMC->Gsvolu("ITS1", "TUBE", idtmed[199], dits, 3);
189 pMC->Gspos("ITS1", 1, "ITSV", 0., 0., 0., 0, "ONLY");
192 dits[1] = rl[1] + drl[1];
194 pMC->Gsvolu("ITS2", "TUBE", idtmed[199], dits, 3);
195 pMC->Gspos("ITS2", 1, "ITSV", 0., 0., 0., 0, "ONLY");
198 dits[1] = rl[2] + drl[2];
200 pMC->Gsvolu("ITS3", "TUBE", idtmed[224], dits, 3);
201 pMC->Gspos("ITS3", 1, "ITSV", 0., 0., 0., 0, "ONLY");
204 dits[1] = rl[3] + drl[3];
206 pMC->Gsvolu("ITS4", "TUBE", idtmed[224], dits, 3);
207 pMC->Gspos("ITS4", 1, "ITSV", 0., 0., 0., 0, "ONLY");
210 dits[1] = rl[4] + drl[4];
212 pMC->Gsvolu("ITS5", "TUBE", idtmed[249], dits, 3);
213 pMC->Gspos("ITS5", 1, "ITSV", 0., 0., 0., 0, "ONLY");
216 dits[1] = rl[5] + drl[5];
218 pMC->Gsvolu("ITS6", "TUBE", idtmed[249], dits, 3);
219 pMC->Gspos("ITS6", 1, "ITSV", 0., 0., 0., 0, "ONLY");
223 // PCB (layer #3 and #4)
225 pMC->Gsvolu("IPCB", "TUBE", idtmed[233], dits, 0);
226 for (i = 2; i < 4; ++i) {
228 dits[1] = dits[0] + drpcb[i];
229 dits[2] = dzb[i] / 2.;
230 zpos = dzl[i] + dits[2];
231 pMC->Gsposp("IPCB", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
232 pMC->Gsposp("IPCB", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
235 // COPPER (layer #3 and #4)
237 pMC->Gsvolu("ICO2", "TUBE", idtmed[234], dits, 0);
238 for (i = 2; i < 4; ++i) {
239 dits[0] = rl[i] + drpcb[i];
240 dits[1] = dits[0] + drcu[i];
241 dits[2] = dzb[i] / 2.;
242 zpos = dzl[i] + dits[2];
243 pMC->Gsposp("ICO2", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
244 pMC->Gsposp("ICO2", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
247 // CERAMICS (layer #3 and #4)
249 pMC->Gsvolu("ICER", "TUBE", idtmed[235], dits, 0);
250 for (i = 2; i < 4; ++i) {
251 dits[0] = rl[i] + drpcb[i] + drcu[i];
252 dits[1] = dits[0] + drcer[i];
253 dits[2] = dzb[i] / 2.;
254 zpos = dzl[i] + dits[2];
255 pMC->Gsposp("ICER", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
256 pMC->Gsposp("ICER", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
259 // SILICON (layer #3 and #4)
261 pMC->Gsvolu("ISI2", "TUBE", idtmed[226], dits, 0);
262 for (i = 2; i < 4; ++i) {
263 dits[0] = rl[i] + drpcb[i] + drcu[i] + drcer[i];
264 dits[1] = dits[0] + drsi[i];
265 dits[2] = dzb[i] / 2.;
266 zpos = dzl[i] + dits[2];
267 pMC->Gsposp("ISI2", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
268 pMC->Gsposp("ISI2", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
271 // PLASTIC (G10FR4) (layer #5 and #6)
273 pMC->Gsvolu("IPLA", "TUBE", idtmed[262], dits, 0);
274 for (i = 4; i < 6; ++i) {
276 dits[1] = dits[0] + drpla[i];
277 dits[2] = dzb[i] / 2.;
278 zpos = dzl[i] + dits[2];
279 pMC->Gsposp("IPLA", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
280 pMC->Gsposp("IPLA", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
283 // COPPER (layer #5 and #6)
285 pMC->Gsvolu("ICO3", "TUBE", idtmed[259], dits, 0);
286 for (i = 4; i < 6; ++i) {
287 dits[0] = rl[i] + drpla[i];
288 dits[1] = dits[0] + drcu[i];
289 dits[2] = dzb[i] / 2.;
290 zpos = dzl[i] + dits[2];
291 pMC->Gsposp("ICO3", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
292 pMC->Gsposp("ICO3", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
295 // EPOXY (layer #5 and #6)
297 pMC->Gsvolu("IEPX", "TUBE", idtmed[262], dits, 0);
298 for (i = 4; i < 6; ++i) {
299 dits[0] = rl[i] + drpla[i] + drcu[i];
300 dits[1] = dits[0] + drepx[i];
301 dits[2] = dzb[i] / 2.;
302 zpos = dzl[i] + dits[2];
303 pMC->Gsposp("IEPX", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
304 pMC->Gsposp("IEPX", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
307 // SILICON (layer #5 and #6)
309 pMC->Gsvolu("ISI3", "TUBE", idtmed[251], dits, 0);
310 for (i = 4; i < 6; ++i) {
311 dits[0] = rl[i] + drpla[i] + drcu[i] + drepx[i];
312 dits[1] = dits[0] + drsi[i];
313 dits[2] = dzb[i] / 2.;
314 zpos = dzl[i] + dits[2];
315 pMC->Gsposp("ISI3", i-1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
316 pMC->Gsposp("ISI3", i+1, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
321 pMC->Gsvolu("ISUP", "TUBE", idtmed[274], dits, 0);
322 for (i = 0; i < 6; ++i) {
324 if (i < 5) dits[1] = rl[i];
327 zpos = dzl[i] + dzb[i] + dits[2];
328 pMC->Gsposp("ISUP", i+1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
329 pMC->Gsposp("ISUP", i+7, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
332 // CABLES (HORIZONTAL)
334 pMC->Gsvolu("ICHO", "TUBE", idtmed[278], dits, 0);
335 for (i = 0; i < 6; ++i) {
337 dits[1] = dits[0] + drca;
338 dits[2] = (rzcone + TMath::Tan(acone) * (rl[i] - rl[0]) - (dzl[i]+ dzb[i] + drsu)) / 2.;
339 zpos = dzl[i - 1] + dzb[i] + drsu + dits[2];
340 pMC->Gsposp("ICHO", i+1, "ITSV", 0., 0., zpos, 0, "ONLY", dits, 3);
341 pMC->Gsposp("ICHO", i+7, "ITSV", 0., 0.,-zpos, 0, "ONLY", dits, 3);
343 // DEFINE A CONICAL GHOST VOLUME FOR THE PHI SEGMENTATION
350 pcits[6] = pcits[3] + TMath::Tan(acone) * (rlim - rl[0]);
351 pcits[7] = rlim - rl[0] + 3.5;
353 pMC->Gsvolu("ICMO", "PCON", idtmed[275], pcits, 9);
354 AliMatrix(idrotm[200], 90., 0., 90., 90., 180., 0.);
355 pMC->Gspos("ICMO", 1, "ITSV", 0., 0., 0., 0, "ONLY");
356 pMC->Gspos("ICMO", 2, "ITSV", 0., 0., 0., idrotm[200], "ONLY");
358 // DIVIDE INTO NSEC PHI-SECTIONS
360 pMC->Gsdvn("ICMD", "ICMO", nsec, 2);
361 pMC->Gsatt("ICMO", "SEEN", 0);
362 pMC->Gsatt("ICMD", "SEEN", 0);
367 pMC->Gsvolu("ICCO", "PCON", idtmed[278], pcits, 0);
368 for (i = 1; i < 6; ++i) {
369 pcits[0] = -dphi[i] / 2.;
372 dzco = TMath::Tan(acone) * (rl[i+1] - rl[i]);
374 dzco1 = zmax - (rzcone + TMath::Tan(acone) * (rl[5] - rl[0])) -2.;
375 dzco2 = (rlim - rl[5]) * TMath::Tan(acone);
376 if (rl[5] + dzco1 / TMath::Tan(acone) < rlim) {
382 pcits[3] = rzcone + TMath::Tan(acone) * (rl[i] - rl[0]);
383 pcits[4] = rl[i] - drcac[i] / TMath::Sin(acone);
385 pcits[6] = pcits[3] + dzco;
386 pcits[7] = rl[i] + dzco / TMath::Tan(acone) - drcac[i] / TMath::Sin(acone);
387 pcits[8] = rl[i] + dzco / TMath::Tan(acone);
389 pMC->Gsposp("ICCO", i, "ICMD", 0., 0., 0., 0, "ONLY", pcits, 9);
395 // CONICAL CABLES BELOW TPC
397 // DEFINE A CONICAL GHOST VOLUME FOR THE PHI SEGMENTATION
403 pcits[4] = pcits[5] - drca_tpc;
405 pcits[8] = pcits[4] + (pcits[6] - pcits[3]) * TMath::Tan(acable * kDegrad);
406 pcits[7] = pcits[8] - drca_tpc;
407 AliMatrix(idrotm[200], 90., 0., 90., 90., 180., 0.);
408 pMC->Gsvolu("ICCM", "PCON", idtmed[275], pcits, 9);
409 pMC->Gspos("ICCM", 1, "ALIC", 0., 0., 0., 0, "ONLY");
410 pMC->Gspos("ICCM", 2, "ALIC", 0., 0., 0., idrotm[200], "ONLY");
411 pMC->Gsdvn("ITMD", "ICCM", nsec, 2);
412 pMC->Gsatt("ITMD", "SEEN", 0);
413 pMC->Gsatt("ICCM", "SEEN", 0);
415 // NOW PLACE SEGMENTS WITH DECREASING PHI SEGMENTS INTO THE
419 pMC->Gsvolu("ITTT", "PCON", idtmed[278], pcits, 0);
422 dz = (xltpc - zend) / 9.;
423 for (i = 0; i < 9; ++i) {
424 zi = z0 + i*dz + dz / 2.;
425 ri = r0 + (zi - z0) * TMath::Tan(acable * kDegrad);
426 dphii = dphi[5] * r0 / ri;
427 pcits[0] = -dphii / 2.;
429 pcits[3] = zi - dz / 2.;
430 pcits[5] = r0 + (pcits[3] - z0) * TMath::Tan(acable * kDegrad);
431 pcits[4] = pcits[5] - drca_tpc;
432 pcits[6] = zi + dz / 2.;
433 pcits[8] = r0 + (pcits[6] - z0) * TMath::Tan(acable * kDegrad);
434 pcits[7] = pcits[8] - drca_tpc;
436 pMC->Gsposp("ITTT", i+1, "ITMD", 0., 0., 0., 0, "ONLY", pcits, 9);
439 // --- Outputs the geometry tree in the EUCLID/CAD format
442 pMC->WriteEuclid("ITSgeometry", "ITSV", 1, 5);
446 //_____________________________________________________________________________
447 void AliITSv1::CreateMaterials()
450 // Create the materials for ITS
452 AliITS::CreateMaterials();
455 //_____________________________________________________________________________
456 void AliITSv1::Init()
459 // Initialise the ITS after it has been built
464 //_____________________________________________________________________________
465 void AliITSv1::DrawModule()
468 // Draw a shaded view of the FMD version 1
471 AliMC* pMC = AliMC::GetMC();
473 // Set everything unseen
474 pMC->Gsatt("*", "seen", -1);
476 // Set ALIC mother visible
477 pMC->Gsatt("ALIC","SEEN",0);
479 // Set the volumes visible
480 pMC->Gsatt("ITSV","SEEN",0);
481 pMC->Gsatt("ITS1","SEEN",1);
482 pMC->Gsatt("ITS2","SEEN",1);
483 pMC->Gsatt("ITS3","SEEN",1);
484 pMC->Gsatt("ITS4","SEEN",1);
485 pMC->Gsatt("ITS5","SEEN",1);
486 pMC->Gsatt("ITS6","SEEN",1);
488 pMC->Gsatt("IPCB","SEEN",1);
489 pMC->Gsatt("ICO2","SEEN",1);
490 pMC->Gsatt("ICER","SEEN",0);
491 pMC->Gsatt("ISI2","SEEN",0);
492 pMC->Gsatt("IPLA","SEEN",0);
493 pMC->Gsatt("ICO3","SEEN",0);
494 pMC->Gsatt("IEPX","SEEN",0);
495 pMC->Gsatt("ISI3","SEEN",1);
496 pMC->Gsatt("ISUP","SEEN",0);
497 pMC->Gsatt("ICHO","SEEN",0);
498 pMC->Gsatt("ICMO","SEEN",0);
499 pMC->Gsatt("ICMD","SEEN",0);
500 pMC->Gsatt("ICCO","SEEN",1);
501 pMC->Gsatt("ICCM","SEEN",0);
502 pMC->Gsatt("ITMD","SEEN",0);
503 pMC->Gsatt("ITTT","SEEN",1);
506 pMC->Gdopt("hide", "on");
507 pMC->Gdopt("shad", "on");
508 pMC->Gsatt("*", "fill", 7);
509 pMC->SetClipBox(".");
510 pMC->SetClipBox("*", 0, 300, -300, 300, -300, 300);
512 pMC->Gdraw("alic", 40, 30, 0, 11, 10, .07, .07);
513 pMC->Gdhead(1111, "Inner Tracking System Version 1");
514 pMC->Gdman(17, 6, "MAN");
517 //_____________________________________________________________________________
518 void AliITSv1::StepManager()
521 // Called at every step in the ITS
528 TClonesArray &lhits = *fHits;
529 AliMC* pMC = AliMC::GetMC();
531 if(pMC->TrackCharge() && pMC->Edep()) {
533 // Only entering charged tracks
534 if((id=pMC->CurrentVol(0,copy))==fIdSens1) {
536 id=pMC->CurrentVolOff(1,0,copy);
538 id=pMC->CurrentVolOff(2,0,copy);
540 } else if(id==fIdSens2) {
542 id=pMC->CurrentVolOff(1,0,copy);
544 id=pMC->CurrentVolOff(2,0,copy);
546 } else if(id==fIdSens3) {
549 id=pMC->CurrentVolOff(1,0,copy);
551 } else if(id==fIdSens4) {
554 id=pMC->CurrentVolOff(1,0,copy);
556 } else if(id==fIdSens5) {
559 id=pMC->CurrentVolOff(1,0,copy);
561 } else if(id==fIdSens6) {
564 id=pMC->CurrentVolOff(1,0,copy);
567 pMC->TrackPosition(position);
568 pMC->TrackMomentum(momentum);
572 hits[3]=momentum[0]*momentum[3];
573 hits[4]=momentum[1]*momentum[3];
574 hits[5]=momentum[2]*momentum[3];
576 new(lhits[fNhits++]) AliITShit(fIshunt,gAlice->CurrentTrack(),vol,hits);