1 ///////////////////////////////////////////////////////////////////////////////
3 // Time Projection Chamber version 1 -- detailed TPC and fast simulation //
7 <img src="picts/AliTPCv1Class.gif">
12 ///////////////////////////////////////////////////////////////////////////////
15 #include <TGeometry.h>
27 #include "AliTPCParam.h"
32 //_____________________________________________________________________________
33 AliTPCv1::AliTPCv1(const char *name, const char *title)
34 :AliTPC(name, title) {
36 // Standard constructor for Time Projection Chamber
41 //_____________________________________________________________________________
42 void AliTPCv1::CreateGeometry()
45 // Creates geometry for Time Projection Chamber version 1
46 // Detailed geometry -- Fast simulation
51 <img src="picts/AliTPCv1.gif">
56 <img src="picts/AliTPCv1Tree.gif">
60 Int_t *idtmed = fIdtmed->GetArray()-399;
63 AliTPCParam * fTPCParam = &(fDigParam->GetParam());
65 Float_t tana, rlsl, wlsl, rssl, rlsu, wssl, wlsu,
66 rssu, wssu, alpha, x, y, z, sec_thick;
68 Float_t r1, r2, x1, z0, z1, x2, theta1, theta2, theta3, dm[21];
79 Float_t thu, opu, phi1, phi2, phi3;
81 // ----------------------------------------------------
82 // FIELD CAGE WITH ENDCAPS - CARBON FIBER
83 // THIS IS ALSO A TPC MOTHER VOLUME
84 // ----------------------------------------------------
89 gMC->Gsvolu("TPC ", "TUBE", idtmed[407], dm, 3);
91 // -------------------------------------------------------
92 // drift gas Ne/CO2 (90/10 volume) - nonsensitive
93 // field cage thickness = 0.52% X0
94 // ----------------------------------------------------
98 <img src="picts/spec_tgas1.gif">
106 gMC->Gsvolu("TGAS", "TUBE", idtmed[402], dm, 3);
108 // ------------------------------------------------------
109 // "side" gas volume (the same as drift gas),
110 // here the readout chambers are positioned
111 // ------------------------------------------------------
115 <img src="picts/spec_tpsg1.gif">
122 gMC->Gsvolu("TPSG", "TUBE", idtmed[401], dm, 3);
123 // ------------------------------------------------------
124 // HV midplane - 20 microns of mylar
125 // -----------------------------------------------------
128 gMC->Gsvolu("TPHV", "TUBE", idtmed[405], dm, 3);
130 // ====================================================
131 // lower and upper readout chambers
132 // ====================================================
133 // sectors opening angles in degrees
134 // ---------------------------------------------------
137 thl = TMath::Tan(opl * .5 * kDegrad);
138 thu = TMath::Tan(opu * .5 * kDegrad);
139 // ---------------------------------------------------
140 // S and L-sectors radii
141 // ---------------------------------------------------
146 // --------------------------------------------------
148 // --------------------------------------------------
153 // ---------------------------------------------------
154 // Sector thickness 25% of X0 (Al)
155 // ---------------------------------------------------
157 // ---------------------------------------------------
158 // S-sectors (lower sectors)
159 // ---------------------------------------------------
162 dm[2] = sec_thick * .5;
163 dm[3] = (rssu - rssl) * .5;
169 <img src="picts/spec_trcs1.gif">
174 gMC->Gsvolu("TRCS", "TRD1", idtmed[399], dm, 4);
175 // -----------------------------------------------------
176 // S-sectors --> "gas sectors"
177 // -----------------------------------------------------
181 <img src="picts/spec_tsga1.gif">
185 dm[2] = (250.-0.001)/2.;
186 gMC->Gsvolu("TSGA", "TRD1", idtmed[402], dm, 4);
187 // ---------------------------------------------------
188 // L-sectors (upper sectors)
189 // ---------------------------------------------------
192 dm[2] = sec_thick * .5;
193 dm[3] = (rlsu - rlsl) * .5;
197 gMC->Gsvolu("TRCL", "TRD1", idtmed[399], dm, 4);
198 // -----------------------------------------------------
199 // L-sectors - "gas sectors"
200 // -----------------------------------------------------
201 dm[2] = (250.-0.001)/2.;
202 gMC->Gsvolu("TLGA", "TRD1", idtmed[402], dm, 4);
203 // -----------------------------------------------------
204 // thin sensitive strips (100 microns) placed at a center
205 // of each pad row in the "drift gas sector"
206 // -----------------------------------------------------
207 gMC->Gsvolu("TSST", "TRD1", idtmed[403], dm, 0);
210 z0 = rssl + (rssu - rssl) * .5;
212 for (iss = 0; iss < fTPCParam->GetNRowLow(); ++iss) {
213 r1 = fTPCParam->GetPadRowRadiiLow(iss);
214 r2 = r1 + dm[3] * 2.;
215 dm[0] = r1 * thl - 2.63;
216 dm[1] = r2 * thl - 2.63;
220 gMC->Gsposp("TSST", iss+1, "TSGA", 0, 0, zz, 0, "ONLY", dm, 4);
222 // -----------------------------------------------------
223 // thin sensitive strips (100 microns) placed at a center
224 // of each pad row in the "drift gas sector"
225 // -----------------------------------------------------
226 gMC->Gsvolu("TLST", "TRD1", idtmed[403], dm, 0);
228 z0 = rlsl+ (rlsu - rlsl) * .5;
230 for (ils = 0; ils < fTPCParam->GetNRowUp(); ++ils) {
231 r1 = fTPCParam->GetPadRowRadiiUp(ils);
232 r2 = r1 + dm[3] * 2.;
233 dm[0] = r1 * thu - 2.63;
234 dm[1] = r2 * thu - 2.63;
236 zz = -z0 + r1 +dm[3];
238 gMC->Gsposp("TLST", ils+1, "TLGA", 0, 0, zz, 0, "ONLY", dm, 4);
240 // ------------------------------------------------
241 // positioning of lower sectors (1-12)*2
242 // rotation matrices 1-12
243 // ------------------------------------------------
245 z1 = -z_side + sec_thick * .5;
247 for (il = 0; il < 12; ++il) {
248 phi1 = il * opl + 270;
259 AliMatrix(idrotm[idr], theta1, phi1, theta2, phi2, theta3, phi3);
261 alpha = il * opl * kDegrad;
262 x = x0l * TMath::Cos(alpha);
263 y = x0l * TMath::Sin(alpha);
265 gMC->Gspos("TSGA", il+1, "TGAS", x, y, z, idrotm[idr], "ONLY");
266 gMC->Gspos("TSGA", il+13,"TGAS", x, y, -z, idrotm[idr], "ONLY");
267 gMC->Gspos("TRCS", il+1, "TPSG", x, y, z1, idrotm[idr], "ONLY");
270 // ----------------------------------------------------
271 // positioning of upper sectors (1-24)*2
272 // rotation matrices 13-36
273 // ----------------------------------------------------
274 for (iu = 1; iu <= 24; ++iu) {
275 phi1 = (iu - 1) * opu + 270.;
282 phi3 = (iu - 1) * opu;
286 AliMatrix(idrotm[idr], theta1, phi1, theta2, phi2, theta3, phi3);
288 alpha = (iu - 1) * opu * kDegrad;
289 x = x0u * TMath::Cos(alpha);
290 y = x0u * TMath::Sin(alpha);
292 gMC->Gspos("TLGA", iu, "TGAS", x, y, z, idrotm[idr], "ONLY");
293 gMC->Gspos("TLGA", iu+24, "TGAS", x, y, -z, idrotm[idr], "ONLY");
295 gMC->Gspos("TRCL", iu, "TPSG", x, y, z1, idrotm[idr], "ONLY");
297 // --------------------------------------------------------
298 // Spoke wheel structures
299 // --------------------------------------------------------
300 gMC->Gsvolu("TSWS", "TUBE", idtmed[399], dm, 0);
308 gMC->Gsposp("TSWS", 1, "TPSG", 0, 0, z0, 0, "ONLY", dm, 3);
313 gMC->Gsposp("TSWS", 2, "TPSG", 0, 0, z0, 0, "ONLY", dm, 3);
318 gMC->Gsposp("TSWS", 3, "TPSG", 0, 0, z0, 0, "ONLY", dm, 3);
320 // -------------------------------------------------------
321 // this volumes are to avoid overlaping
322 // -------------------------------------------------------
328 gMC->Gsposp("TSWS", 4, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
329 gMC->Gsposp("TSWS", 5, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
333 gMC->Gsposp("TSWS", 6, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
334 gMC->Gsposp("TSWS", 7, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
337 dm[1] = 257.+0.09776;
342 gMC->Gsposp("TSWS", 8, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
343 gMC->Gsposp("TSWS", 9, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
344 // ==========================================================
346 // ==========================================================
347 // ----------------------------------------------------------
348 // Large wheel -> positioned in the TPC
349 // ----------------------------------------------------------
350 dm[0] = 257.+0.09776;
353 gMC->Gsvolu("TPW1", "TUBE", idtmed[399], dm, 3);
359 gMC->Gsvolu("TPW2", "TUBE", idtmed[498], dm, 3);
361 gMC->Gspos("TPW2", 1, "TPW1", 0, 0, 0, 0, "ONLY");
363 gMC->Gspos("TPW1", 1, "TPC ", 0, 0, z0, 0, "ONLY");
364 gMC->Gspos("TPW1", 2, "TPC ", 0, 0, -z0, 0, "ONLY");
365 // -----------------------------------------------------------
366 // Small wheel -> positioned in the TPSG
367 // -----------------------------------------------------------
372 gMC->Gsvolu("TPW3", "TUBE", idtmed[399], dm, 3);
378 gMC->Gsvolu("TPW4", "TUBE", idtmed[401], dm, 3);
380 gMC->Gspos("TPW4", 1, "TPW3", 0, 0, 0, 0, "ONLY");
384 gMC->Gspos("TPW3", 1, "TPSG", 0, 0, z0, 0, "ONLY");
385 // ---------------------------------------------------------
386 // spokes, inner and outer, also the inner ring
387 // ---------------------------------------------------------
391 <img src="picts/spec_tspo1.gif">
395 dm[0] = 0.5*(135.9-82.1);
401 gMC->Gsvolu("TSPI", "BOX ", idtmed[399], dm, 3);
406 gMC->Gsvolu("TSP1", "BOX ", idtmed[498], dm, 3);
408 gMC->Gspos("TSP1", 1, "TSPI", 0, 0, 0, 0, "ONLY");
410 dm[0] = 0.5*(256.9-142.1);
416 gMC->Gsvolu("TSPO", "BOX ", idtmed[399], dm, 3);
421 gMC->Gsvolu("TSP2", "BOX ", idtmed[498], dm, 3);
423 gMC->Gspos("TSP2", 1, "TSPO", 0, 0, 0, 0, "ONLY");
424 // --------------------------------------------------------
429 gMC->Gsvolu("TSWH", "TUBE", idtmed[399], dm, 3);
435 gMC->Gsvolu("TSW1", "TUBE", idtmed[498], dm, 3);
437 gMC->Gspos("TSW1", 1, "TSWH", 0, 0, 0, 0, "ONLY");
439 z0 = z_side - .16168 - 2.;
440 // --------------------------------------------------------
441 gMC->Gspos("TSWH", 1, "TPSG", 0, 0, z0, 0, "ONLY");
442 // -------------------------------------------------------
443 // posiioning of the inner spokes
444 // -------------------------------------------------------
445 for (il = 1; il <= 6; ++il) {
446 phi1 = opl * .5 + (il - 1) * 2. * opl;
448 phi2 = opl * .5 + 90. + (il - 1) * 2. * opl;
456 alpha = phi1 * kDegrad;
457 x = x1 * TMath::Cos(alpha);
458 y = x1 * TMath::Sin(alpha);
462 AliMatrix(idrotm[idr], theta1, phi1, theta2, phi2, theta3, phi3);
463 gMC->Gspos("TSPI", il, "TPSG", x, y, z0, idrotm[idr], "ONLY");
466 for (iu = 1; iu <= 12; ++iu) {
467 phi1 = opu * .5 + (iu - 1) * 2. * opu;
469 phi2 = opu * .5 + 90. + (iu - 1) * 2. * opu;
477 alpha = phi1 * kDegrad;
478 x = x2 * TMath::Cos(alpha);
479 y = x2 * TMath::Sin(alpha);
483 AliMatrix(idrotm[idr], theta1, phi1, theta2, phi2, theta3, phi3);
484 gMC->Gspos("TSPO", iu, "TPSG", x, y, z0, idrotm[idr], "ONLY");
486 // --------------------------------------------------------
487 // endcap cover (C, 0.86% X0)
488 // --------------------------------------------------------
493 gMC->Gsvolu("TCOV", "TUBE", idtmed[407], dm, 3);
497 gMC->Gspos("TCOV", 1, "TPSG", 0, 0, z0, 0, "ONLY");
498 // --------------------------------------------------------
499 // put the readout chambers into the TPC
500 // --------------------------------------------------------
508 AliMatrix(idrotm[55], theta1, phi1, theta2, phi2, theta3, phi3);
512 gMC->Gspos("TPSG", 1, "TPC ", 0, 0, z0, 0, "ONLY");
513 gMC->Gspos("TPSG", 2, "TPC ", 0, 0, -z0, idrotm[55], "ONLY");
514 // ---------------------------------------------------------
515 // outer gas insulation (CO2)
516 // ---------------------------------------------------------
517 dm[0] = 257.+0.09776;
518 dm[1] = 278.-0.25004;
521 gMC->Gsvolu("TPOI", "TUBE", idtmed[406], dm, 3);
523 gMC->Gspos("TPHV", 1, "TGAS", 0, 0, 0, 0, "ONLY");
524 gMC->Gspos("TGAS", 1, "TPC ", 0, 0, 0, 0, "ONLY");
525 gMC->Gspos("TPOI", 1, "TPC ", 0, 0, 0, 0, "ONLY");
527 gMC->Gspos("TPC ", 1, "ALIC", 0, 0, 0, 0, "ONLY");
528 // ======================================================
529 // all volumes below are positioned in ALIC
530 // ======================================================
531 // ------------------------------------------------------
532 // the last parts of the smaller wheel (TSWS)
533 // ------------------------------------------------------
540 gMC->Gsposp("TSWS", 10, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
541 gMC->Gsposp("TSWS", 11, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
547 gMC->Gsposp("TSWS", 12, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
548 gMC->Gsposp("TSWS", 13, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
549 // ----------------------------------------------------
550 // Inner vessel (PCON)
551 // This volume is to be positioned directly in ALIC
552 // ----------------------------------------------------
556 <img src="picts/spec_tpiv1.gif">
580 gMC->Gsvolu("TPIV", "PCON", idtmed[407], dm, 15);
581 // --------------------------------------------------------
582 // fill the inner vessel with CO2, (HV kDegrader)
583 // cone parts have different thickness
584 // than the central barrel, according to the TP
585 // --------------------------------------------------------
592 dm[3] = -(250.-0.2162);
593 dm[4] = (185.5-0.2126)*tana+0.2126;
612 dm[18] = (250.-0.2162);
613 dm[19] = (185.5-0.2126)*tana+0.2126;
616 gMC->Gsvolu("TPVD", "PCON", idtmed[406], dm, 21);
618 gMC->Gspos("TPVD", 1, "TPIV", 0, 0, 0, 0, "ONLY");
620 gMC->Gspos("TPIV", 1, "ALIC", 0, 0, 0, 0, "ONLY");
621 // ---------------------------------------------------
623 // ---------------------------------------------------
624 gMC->Gsord("TGAS", 6);
625 gMC->Gsord("TPSG", 6);
626 gMC->Gsord("TSGA", 3);
627 gMC->Gsord("TLGA", 3);
630 //_____________________________________________________________________________
631 void AliTPCv1::DrawDetector()
634 // Draw a shaded view of the Time Projection Chamber version 1
637 // Set everything unseen
638 gMC->Gsatt("*", "seen", -1);
640 // Set ALIC mother transparent
641 gMC->Gsatt("ALIC","SEEN",0);
643 // Set the volumes visible
644 gMC->Gsatt("TPC","SEEN",0);
645 gMC->Gsatt("TGAS","SEEN",0);
646 gMC->Gsatt("TPSG","SEEN",0);
647 gMC->Gsatt("TPHV","SEEN",1);
648 gMC->Gsatt("TRCS","SEEN",1);
649 gMC->Gsatt("TRCL","SEEN",1);
650 gMC->Gsatt("TSST","SEEN",1);
651 gMC->Gsatt("TLST","SEEN",1);
652 gMC->Gsatt("TSWS","SEEN",1);
653 gMC->Gsatt("TPW1","SEEN",1);
654 gMC->Gsatt("TPW2","SEEN",1);
655 gMC->Gsatt("TPW3","SEEN",1);
656 gMC->Gsatt("TPW4","SEEN",1);
657 gMC->Gsatt("TSPI","SEEN",1);
658 gMC->Gsatt("TSP1","SEEN",0);
659 gMC->Gsatt("TSPO","SEEN",1);
660 gMC->Gsatt("TSP2","SEEN",0);
661 gMC->Gsatt("TSWH","SEEN",1);
662 gMC->Gsatt("TSW1","SEEN",1);
663 gMC->Gsatt("TCOV","SEEN",0);
664 gMC->Gsatt("TPOI","SEEN",1);
665 gMC->Gsatt("TPIV","SEEN",1);
666 gMC->Gsatt("TPVD","SEEN",1);
668 gMC->Gdopt("hide", "on");
669 gMC->Gdopt("shad", "on");
670 gMC->Gsatt("*", "fill", 7);
671 gMC->SetClipBox(".");
672 gMC->SetClipBox("*", 0, 1000, -1000, 1000, -1000, 1000);
674 gMC->Gdraw("alic", 40, 30, 0, 12, 9.5, .025, .025);
675 gMC->Gdhead(1111, "Time Projection Chamber");
676 gMC->Gdman(18, 4, "MAN");
677 gMC->Gdopt("hide","off");
680 //_____________________________________________________________________________
681 void AliTPCv1::CreateMaterials()
684 // Define materials for Time Projection Chamber
686 AliTPC::CreateMaterials();
689 //_____________________________________________________________________________
690 void AliTPCv1::Init()
693 // Initialises TPC detector after it has been created
696 fIdSens1=gMC->VolId("TLST");
697 fIdSens2=gMC->VolId("TSST");
699 printf("TPC version 1 initialized\n");
702 //_____________________________________________________________________________
703 void AliTPCv1::StepManager()
706 // Called at every step in the Time Projection Chamber
712 TClonesArray &lhits = *fHits;
715 if(gMC->TrackCharge() && gMC->IsTrackEntering()) {
717 // Only entering charged tracks
718 if((id=gMC->CurrentVolID(copy))==fIdSens1) {
720 id=gMC->CurrentVolOffID(1,copy);
722 } else if(id==fIdSens2) {
724 id=gMC->CurrentVolOffID(1,copy);
727 gMC->TrackPosition(p);
728 for(i=0;i<3;++i) hits[i]=p[i];
730 new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);