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njacazionjacazio
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IOTOF: align geometry to specs
- add macro to draw geometry - streamline setup of IOTOF active layers
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4 files changed

Lines changed: 156 additions & 19 deletions

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‎Detectors/Upgrades/ALICE3/IOTOF/macros/CMakeLists.txt‎

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o2_add_test_root_macro(defineIOTOFGeo.C
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LABELS alice3)
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o2_add_test_root_macro(drawTOFGeometry.C
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LABELS alice3)

‎Detectors/Upgrades/ALICE3/IOTOF/macros/drawTOFGeometry.C‎

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// Copyright 2019-2020 CERN and copyright holders of ALICE O2.
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// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
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// All rights not expressly granted are reserved.
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//
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// This software is distributed under the terms of the GNU General Public
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// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
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//
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// In applying this license CERN does not waive the privileges and immunities
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// granted to it by virtue of its status as an Intergovernmental Organization
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// or submit itself to any jurisdiction.
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#include "IOTOFBase/GeometryTGeo.h"
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#include "IOTOFSimulation/Layer.h"
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#include <TCanvas.h>
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#include <TGeoManager.h>
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#include <TGeoMaterial.h>
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#include <TGeoMatrix.h>
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#include <TGeoVolume.h>
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#include <TStyle.h>
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#include <iostream>
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namespace
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{
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void ensureMedium(const char* name, int id, double a, double z, double density)
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{
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if (!gGeoManager->GetMedium(name)) {
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auto* mat = new TGeoMaterial(name, a, z, density);
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new TGeoMedium(name, id, mat);
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}
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}
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void prepareMinimalMedia()
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{
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ensureMedium("VACUUM$", 0, 1., 1., 1.e-16);
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ensureMedium("TF3_AIR$", 1, 14.61, 7.3, 1.20479e-3);
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ensureMedium("TF3_SILICON$", 3, 28.086, 14., 2.33);
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}
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} // namespace
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void drawTOFGeometry(double x2x0 = 0.02,
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double sensorThickness = 0.005,
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bool checkOverlaps = true,
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double overlapToleranceCm = 0.01)
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{
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gStyle->SetOptStat(0);
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if (gGeoManager) {
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delete gGeoManager;
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}
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auto* geo = new TGeoManager("IOTOFGeomFromLayer", "Geometry built from Layer.h classes");
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prepareMinimalMedia();
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auto* top = geo->MakeBox("TOP", geo->GetMedium("VACUUM$"), 1200., 1200., 1200.);
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geo->SetTopVolume(top);
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auto* mother = new TGeoVolumeAssembly("IOTOFMacroVol");
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top->AddNode(mother, 1, new TGeoTranslation(0., 0., 0.));
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// Build using the same classes and createLayer() used by detector geometry code.
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o2::iotof::ITOFLayer itof(o2::iotof::GeometryTGeo::getITOFLayerPattern(),
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21.f, 0.f, 129.f, 0.f, x2x0,
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o2::iotof::Layer::kBarrelSegmented,
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24, 5.42, 3.0, 10, sensorThickness);
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o2::iotof::OTOFLayer otof(o2::iotof::GeometryTGeo::getOTOFLayerPattern(),
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92.f, 0.f, 680.f, 0.f, x2x0,
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o2::iotof::Layer::kBarrelSegmented,
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62, 9.74, 5.0, 54, sensorThickness);
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itof.createLayer(mother);
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otof.createLayer(mother);
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geo->CloseGeometry();
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std::cout << "Built geometry from Layer.h classes with x2x0=" << x2x0
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<< " and sensorThickness=" << sensorThickness << " cm\n";
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std::cout << "ITOF sensitive volumes: " << o2::iotof::ITOFLayer::mRegister.size() << "\n";
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std::cout << "OTOF sensitive volumes: " << o2::iotof::OTOFLayer::mRegister.size() << "\n";
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if (checkOverlaps) {
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std::cout << "Checking overlaps with tolerance=" << overlapToleranceCm << " cm\n";
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geo->CheckOverlaps(overlapToleranceCm);
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geo->PrintOverlaps();
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}
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top->Draw("ogl");
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}

‎Detectors/Upgrades/ALICE3/IOTOF/simulation/src/Detector.cxx‎

Lines changed: 24 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -200,28 +200,47 @@ void Detector::defineSensitiveVolumes()
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TGeoManager* geoManager = gGeoManager;
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TGeoVolume* v;
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// The names of the IOTOF sensitive volumes have the format: IOTOFLayer(0...mLayers.size()-1)
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auto& iotofPars = IOTOFBaseParam::Instance();
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if (iotofPars.enableInnerTOF) {
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const bool itof = iotofPars.enableInnerTOF;
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const bool otof = iotofPars.enableOuterTOF;
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bool ftof = iotofPars.enableForwardTOF;
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bool btof = iotofPars.enableBackwardTOF;
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const std::string pattern = iotofPars.detectorPattern;
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if (pattern == "") {
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LOG(info) << "Default pattern";
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} else if (pattern == "v3b") {
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ftof = false;
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btof = false;
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} else if (pattern == "v3b1a") {
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} else if (pattern == "v3b1b") {
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} else if (pattern == "v3b2a") {
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} else if (pattern == "v3b2b") {
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} else if (pattern == "v3b3") {
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} else {
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LOG(fatal) << "IOTOF layer pattern " << pattern << " not recognized, exiting";
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}
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// The names of the IOTOF sensitive volumes have the format: IOTOFLayer(0...mLayers.size()-1)
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if (itof) {
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for (const std::string& itofSensor : ITOFLayer::mRegister) {
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v = geoManager->GetVolume(itofSensor.c_str());
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LOGP(info, "Adding IOTOF Sensitive Volume {}", v->GetName());
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AddSensitiveVolume(v);
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}
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}
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if (iotofPars.enableOuterTOF) {
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if (otof) {
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for (const std::string& otofSensor : OTOFLayer::mRegister) {
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v = geoManager->GetVolume(otofSensor.c_str());
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LOGP(info, "Adding IOTOF Sensitive Volume {}", v->GetName());
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AddSensitiveVolume(v);
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}
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}
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if (iotofPars.enableForwardTOF) {
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if (ftof) {
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v = geoManager->GetVolume(GeometryTGeo::getFTOFSensorPattern());
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LOGP(info, "Adding IOTOF Sensitive Volume {}", v->GetName());
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AddSensitiveVolume(v);
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}
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if (iotofPars.enableBackwardTOF) {
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if (btof) {
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v = geoManager->GetVolume(GeometryTGeo::getBTOFSensorPattern());
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LOGP(info, "Adding IOTOF Sensitive Volume {}", v->GetName());
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AddSensitiveVolume(v);

‎Detectors/Upgrades/ALICE3/IOTOF/simulation/src/Layer.cxx‎

Lines changed: 39 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -296,12 +296,24 @@ void OTOFLayer::createLayer(TGeoVolume* motherVolume)
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case kBarrelSegmented: {
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// First we create the volume for the whole layer, which will be used as mother volume for the segments
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const double avgRadius = 0.5 * (mInnerRadius + mOuterRadius);
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const double staveSizeX = mStaves.second; // cm
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const double staveSizeY = mOuterRadius - mInnerRadius; // cm
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const double staveSizeZ = mZLength; // cm
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const double deltaForTilt = 0.5 * (std::sin(TMath::DegToRad() * mTiltAngle) * staveSizeX + std::cos(TMath::DegToRad() * mTiltAngle) * staveSizeY); // we increase the size of the layer to account for the tilt of the staves
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const double radiusMax = std::sqrt(avgRadius * avgRadius + 0.25 * staveSizeX * staveSizeX + 0.25 * staveSizeY * staveSizeY + avgRadius * 2. * deltaForTilt); // we increase the outer radius to account for the tilt of the staves
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const double radiusMin = std::sqrt(avgRadius * avgRadius + 0.25 * staveSizeX * staveSizeX + 0.25 * staveSizeY * staveSizeY - avgRadius * 2. * deltaForTilt); // we decrease the inner radius to account for the tilt of the staves
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const double staveSizeX = mStaves.second; // cm, tangential stave size
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const double staveSizeY = mOuterRadius - mInnerRadius; // cm, radial stave size
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const double staveSizeZ = mZLength; // cm
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// Build the mother layer tube from the exact inscribed/outscribed radii of a tilted stave rectangle.
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const double alpha = mTiltAngle * TMath::DegToRad();
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const double u0 = -avgRadius * std::cos(alpha);
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const double v0 = avgRadius * std::sin(alpha);
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const double uClamped = std::max(-0.5 * staveSizeY, std::min(0.5 * staveSizeY, u0));
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const double vClamped = std::max(-0.5 * staveSizeX, std::min(0.5 * staveSizeX, v0));
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const double radiusMin = std::hypot(uClamped - u0, vClamped - v0);
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const double uCorners[4] = {-0.5 * staveSizeY, 0.5 * staveSizeY, 0.5 * staveSizeY, -0.5 * staveSizeY};
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const double vCorners[4] = {-0.5 * staveSizeX, -0.5 * staveSizeX, 0.5 * staveSizeX, 0.5 * staveSizeX};
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double radiusMax = 0.0;
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for (int i = 0; i < 4; ++i) {
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radiusMax = std::max(radiusMax, std::hypot(uCorners[i] - u0, vCorners[i] - v0));
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}
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TGeoTube* layer = new TGeoTube(radiusMin, radiusMax, mZLength / 2);
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TGeoVolume* layerVol = new TGeoVolume(mLayerName.c_str(), layer, medAir);
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setLayerStyle(layerVol);
@@ -312,10 +324,21 @@ void OTOFLayer::createLayer(TGeoVolume* motherVolume)
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setStaveStyle(staveVol);
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// Now we create the volume for a single module (sensor + chip)
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const int modulesPerStaveX = 1; // we assume that each stave is divided in 2 modules along the x direction
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const double moduleSizeX = staveSizeX / modulesPerStaveX; // cm
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const double moduleSizeY = staveSizeY; // cm
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const double moduleSizeZ = staveSizeZ / mModulesPerStave; // cm
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// oTOF V2 is a 2xN matrix of modules per stave with overlap along z.
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const int modulesPerStaveX = 2;
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if (mModulesPerStave % modulesPerStaveX != 0) {
330+
LOG(fatal) << "Invalid oTOF module layout: total modules per stave " << mModulesPerStave
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<< " is not divisible by modulesPerStaveX=" << modulesPerStaveX;
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}
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const int modulesPerStaveZ = mModulesPerStave / modulesPerStaveX;
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const double moduleOverlapZ = 0.7; // cm, 7 mm longitudinal overlap from oTOF V2 specs
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const double moduleSizeX = staveSizeX / modulesPerStaveX;
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const double moduleSizeY = staveSizeY;
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const double moduleSizeZ = (staveSizeZ + (modulesPerStaveZ - 1) * moduleOverlapZ) / modulesPerStaveZ;
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const double modulePitchZ = moduleSizeZ - moduleOverlapZ;
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if (modulePitchZ <= 0.0) {
340+
LOG(fatal) << "Invalid oTOF module overlap " << moduleOverlapZ << " cm for module size " << moduleSizeZ << " cm";
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}
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TGeoBBox* module = new TGeoBBox(moduleSizeX * 0.5, moduleSizeY * 0.5, moduleSizeZ * 0.5);
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TGeoVolume* moduleVol = new TGeoVolume(moduleName, module, medAir);
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setModuleStyle(moduleVol);
@@ -363,10 +386,12 @@ void OTOFLayer::createLayer(TGeoVolume* motherVolume)
363386

364387
// Now we build a stave from modules
365388
for (int i = 0; i < modulesPerStaveX; ++i) {
366-
for (int j = 0; j < mModulesPerStave; ++j) {
367-
LOGP(info, "oTOF: Creating module {}/{} for stave {}/{}", i + 1, modulesPerStaveX, j + 1, mModulesPerStave);
368-
auto* translation = new TGeoTranslation((i + 0.5) * moduleSizeX - 0.5 * staveSizeX, 0, (j + 0.5) * moduleSizeZ - 0.5 * staveSizeZ);
369-
staveVol->AddNode(moduleVol, 1 + i * mModulesPerStave + j, translation);
389+
for (int j = 0; j < modulesPerStaveZ; ++j) {
390+
LOGP(info, "oTOF: Creating module {}/{} for stave {}/{}", i + 1, modulesPerStaveX, j + 1, modulesPerStaveZ);
391+
const double tx = (i + 0.5) * moduleSizeX - 0.5 * staveSizeX;
392+
const double tz = -0.5 * staveSizeZ + 0.5 * moduleSizeZ + j * modulePitchZ;
393+
auto* translation = new TGeoTranslation(tx, 0, tz);
394+
staveVol->AddNode(moduleVol, 1 + i * modulesPerStaveZ + j, translation);
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}
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}
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