SCT_FwdWheel.cxx

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/*
  Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
*/
 
#include "SCT_FwdWheel.h"
 
#include "SCT_MaterialManager.h"
 
#include "SCT_GeometryManager.h"
#include "SCT_ForwardParameters.h"
#include "SCT_GeneralParameters.h"
 
#include "SCT_FwdModule.h"
#include "SCT_FwdRing.h"
#include "SCT_FwdDiscSupport.h"
#include "SCT_FwdPatchPanel.h"
#include "SCT_FwdPPConnector.h"
#include "SCT_FwdPPCooling.h"
#include "SCT_FwdFSI.h"
#include "SCT_FwdDiscPowerTape.h"
#include "SCT_FwdRingCooling.h"
#include "SCT_FwdOptoHarness.h"
#include "SCT_FwdDiscFixation.h"
 
#include "SCT_FSIHelper.h"
 
#include "InDetGeoModelUtils/ExtraMaterial.h"
#include "SCT_ReadoutGeometry/SCT_DetectorManager.h"
 
#include "GeoModelRead/ReadGeoModel.h"
#include "GeoModelKernel/GeoTube.h"
#include "GeoModelKernel/GeoLogVol.h"
#include "GeoModelKernel/GeoPhysVol.h"
#include "GeoModelKernel/GeoFullPhysVol.h"
#include "GeoModelKernel/GeoNameTag.h"
#include "GeoModelKernel/GeoIdentifierTag.h"
#include "GeoModelKernel/GeoTransform.h"
#include "GeoModelKernel/GeoAlignableTransform.h"
#include "GeoModelKernel/GeoMaterial.h"
#include "GeoModelKernel/GeoShapeShift.h"
#include "GeoModelKernel/GeoDefinitions.h"
#include "GaudiKernel/SystemOfUnits.h"
 
#include <sstream>
#include <cmath>
 
#include <iostream>
#include <utility>
 
inline double sqr(double x) {return x*x;}
 
SCT_FwdWheel::SCT_FwdWheel(const std::string & name,
                           int iWheel,
                           const std::vector<SCT_FwdModule *> & modules,
                           int ec,
                           InDetDD::SCT_DetectorManager* detectorManager,
                           SCT_GeometryManager* geometryManager,
                           SCT_MaterialManager* materials,
                           GeoModelIO::ReadGeoModel* sqliteReader,
                           std::shared_ptr<std::map<std::string, GeoFullPhysVol*>>        mapFPV,
                           std::shared_ptr<std::map<std::string, GeoAlignableTransform*>> mapAX)
  : SCT_UniqueComponentFactory(name, detectorManager, geometryManager, materials, sqliteReader, std::move(mapFPV), std::move(mapAX)),
    m_iWheel(iWheel), 
    m_endcap(ec),
    m_modules(modules)
{
  getParameters();
  m_logVolume = SCT_FwdWheel::preBuild();
  
}
 
SCT_FwdWheel::~SCT_FwdWheel()
{
}
 
void
SCT_FwdWheel::getParameters()
{
    const SCT_ForwardParameters * parameters = m_geometryManager->forwardParameters();
    
    m_zPosition = parameters->fwdWheelZPosition(m_iWheel);
    m_numRings  = parameters->fwdWheelNumRings(m_iWheel);
    for (int iRing = 0; iRing < m_numRings; iRing++) {
        m_ringType.push_back(parameters->fwdWheelModuleType(m_iWheel,iRing, m_endcap));
    }
    
    if(!m_sqliteReader){
        
        m_numPatchPanelLocs =  parameters->fwdNumPatchPanelLocs();
        m_numPatchPanelTypes = parameters->fwdNumPatchPanelTypes();
        
        for (int iPPLoc = 0; iPPLoc < m_numPatchPanelLocs; iPPLoc++) {
            m_patchPanelType.push_back(parameters->fwdPatchPanelType(iPPLoc));
            m_patchPanelLocAngle.push_back(parameters->fwdPatchPanelLocAngle(iPPLoc));
            m_patchPanelRepeatQuadrant.push_back(parameters->fwdPatchPanelRepeatQuadrant(iPPLoc));
        }
        
        // FIXME: Check and put these in DB or calculate them
        // We have a maximum width of 80.2. Make it 75 for some clearance.
        //m_innerRadius = 267 * Gaudi::Units::mm;
        //m_outerRadius = 590 * Gaudi::Units::mm;
        //m_thickness = 100 * Gaudi::Units::mm;
        // These get swapped later if the wheel is rotated.
        m_thicknessFront = 30 * Gaudi::Units::mm;
        m_thicknessBack  = 45 * Gaudi::Units::mm;
        
        m_numFSITypes = parameters->fwdFSINumGeomTypes();
        m_fsiVector =  &(parameters->fsiVector(m_iWheel));
        
        m_numWheels    = parameters->fwdNumWheels();
        
        m_optoHarnessPresent = parameters->fwdOptoHarnessPresent();
        m_pPConnectorPresent = parameters->fwdPPConnectorPresent();
        m_pPCoolingPresent = parameters->fwdPPCoolingPresent();
        
        m_discFixationPresent = parameters->fwdDiscFixationPresent();
        if(m_discFixationPresent) {
            for (int iLoc = 0; iLoc < parameters->fwdNumCylinderServiceLocs(); iLoc++) {
                // Disc fixations are at same locations at as N2 pipes
                if(parameters->fwdCylinderServiceLocName(iLoc) == "NPipe") {
                    m_discFixationLocAngle.push_back(parameters->fwdCylinderServiceLocAngle(iLoc));
                }
            }
        }
        
        m_safety = m_geometryManager->generalParameters()->safety();
    }
    
    // Set numerology
    m_detectorManager->numerology().setNumRingsForDisk(m_iWheel,m_numRings);
 
}
 
const GeoLogVol * 
SCT_FwdWheel::preBuild()
{
    // The rings
    for (int iRing = 0; iRing < m_numRings; iRing++){
        std::string ringName = "Ring"+intToString(iRing)+"For"+getName();
        int ringType = m_ringType[iRing];
        m_rings.push_back(std::make_unique<SCT_FwdRing>(ringName, m_modules[ringType], m_iWheel, iRing, m_endcap,m_detectorManager, m_geometryManager, m_materials, m_sqliteReader, m_mapFPV,m_mapAX));
    }
    
    if(m_sqliteReader) return nullptr;
    
    // Calculate total number of modules
    m_totalModules = 0;
    for (int iRing = 0; iRing < m_numRings; iRing++){
        m_totalModules += m_rings[iRing]->numModules();
    }
    
    // Create disc support.
    m_discSupport = std::make_unique<SCT_FwdDiscSupport>("DiscSupport"+intToString(m_iWheel), m_iWheel,
                                                         m_detectorManager, m_geometryManager, m_materials);
    
    
    // Create Patch Panel
    for (int iPPType = 0; iPPType < m_numPatchPanelTypes; iPPType++) {
        m_patchPanel.push_back(std::make_unique<SCT_FwdPatchPanel>("PatchPanel"+intToString(iPPType), iPPType,
                                                                   m_detectorManager, m_geometryManager, m_materials));
    }
    
    // Create Patch Pannel Connector and Cooling, and disc Fixations
    if (m_pPConnectorPresent) {
        m_pPConnector = std::make_unique<SCT_FwdPPConnector>("PPConnector",
                                                             m_detectorManager, m_geometryManager, m_materials);
    }
    if (m_pPCoolingPresent) {
        m_pPCooling = std::make_unique<SCT_FwdPPCooling>("PPCooling",
                                                         m_detectorManager, m_geometryManager, m_materials);
    }
    if (m_discFixationPresent) {
        m_discFixation = std::make_unique<SCT_FwdDiscFixation>("DiscFixation",
                                                               m_detectorManager, m_geometryManager, m_materials);
    }
    
    // Create the FSI types
    m_fsiType.resize(m_numFSITypes);
    for (unsigned int iFSI = 0; iFSI < m_fsiVector->size(); iFSI++) {
        int type = (*m_fsiVector)[iFSI]->simType();
        if (!m_fsiType[type]) {
            m_fsiType[type] = std::make_unique<SCT_FwdFSI>("FSI"+intToString(type), type,
                                                           m_detectorManager, m_geometryManager, m_materials);
        }
    }
    
    // Calculate the extent of the envelope
    // Use support disc as starting values.
    double maxOuterRadius = m_discSupport->outerRadius();
    double minInnerRadius = m_discSupport->innerRadius();
    double maxModuleThickness = 0.5 * m_discSupport->thickness();
    
    
    // Extend min max accounting for rings
    for (int iRing = 0; iRing < m_numRings; iRing++){
        maxOuterRadius = std::max(m_rings[iRing]->outerRadius(), maxOuterRadius);
        minInnerRadius = std::min(m_rings[iRing]->innerRadius(), minInnerRadius);
        maxModuleThickness = std::max(maxModuleThickness, m_rings[iRing]->thicknessOuter() +  m_rings[iRing]->ringOffset());
    }
    m_ringMaxRadius = maxOuterRadius;
    
    // If first or last wheel there is nothing protruding beyond the rings so we reduce the
    // envelope size. Comes to about 20 mm. Note the front becomes the back later for the last wheel.
    if ((m_iWheel == 0) || (m_iWheel == m_numWheels - 1)) {
        m_thicknessFront = maxModuleThickness + 1*Gaudi::Units::mm; // We give plenty of safety as we have the room.
        // But now modified by disc fixations
        if(m_discFixationPresent) {
            m_thicknessFront = std::max(m_thicknessFront,m_discFixation->radius() + m_safety);
        }
    }
    
    // The outer radius is now defined by the patch panel cooling if present
    if(m_pPCoolingPresent) {
        double ppCoolingOuterRadius = sqrt(sqr(m_patchPanel[2]->outerRadius() + m_pPCooling->deltaR()) + sqr(m_pPCooling->rphi())) + m_safety;
        maxOuterRadius = std::max(ppCoolingOuterRadius, maxOuterRadius);
    }
    
    // Or maybe by the disc fixations...
    if(m_discFixationPresent) {
        double discFixationOuterRadius = sqrt(sqr(m_ringMaxRadius + m_discFixation->thickness() + m_safety) + sqr(m_discFixation->radius())) + m_safety;
        maxOuterRadius = std::max(discFixationOuterRadius, maxOuterRadius);
    }
    
    m_rotateWheel = +1; // +1 normal, -1 rotate (ie last wheel)
    if (m_numRings > 0) { // Should always be true
        m_rotateWheel = (m_rings[0]->discRotated()) ? -1 : +1 ;
    }
    
    // swap thickness front/back (this only happens for the last wheel).
    if (m_rotateWheel < 0) {
        double tmp = m_thicknessFront;
        m_thicknessFront = m_thicknessBack;
        m_thicknessBack  = tmp;
    }
    
    m_thickness =  m_thicknessFront +  m_thicknessBack;
    
    m_innerRadius = minInnerRadius - m_safety;
    m_outerRadius = maxOuterRadius + m_safety;
    
    
    // TODO. Have to account for FSI and patch panels
    //m_thickness   = 2. * maxRingOffset + maxThickness;
    // m_thickness  = 100 * Gaudi::Units::mm;
    
    // Make envelope for the wheel
    double envelopeShift = 0.5*(m_thicknessBack - m_thicknessFront);
    const GeoTube * tmpShape = new GeoTube(m_innerRadius, m_outerRadius, 0.5 * m_thickness);
    const GeoShape & fwdWheelEnvelopeShape = *tmpShape <<  GeoTrf::Translate3D(0, 0, envelopeShift);
    
    const GeoLogVol * fwdWheelLog =
    new GeoLogVol(getName(), &fwdWheelEnvelopeShape, m_materials->gasMaterial());
    
    
    return fwdWheelLog;
 
}
 
GeoVPhysVol * 
SCT_FwdWheel::build(SCT_Identifier id)
{
    
    if(m_sqliteReader) {
        
        for (int iRing = 0; iRing < m_numRings; iRing++){
            
            SCT_FwdRing * ring = m_rings[iRing].get();
            id.setEtaModule(ring->identifier());
            ring->build(id);
        
        }
        return nullptr;
        
    }
    
    GeoFullPhysVol * wheel= new GeoFullPhysVol(m_logVolume);
    
    
    // Add discsupport. Its centered so no need for a transform
    wheel->add(m_discSupport->getVolume());
    
    //
    // Loop over rings and put in rings, cooling and power tapes.
    //
    double powerTapeZPlusMax = 0.5 * m_discSupport->thickness();
    double powerTapeZMinusMax = -0.5 * m_discSupport->thickness();
    
    double maxZOfRingsFront = 0;
    
    for (int iRing = 0; iRing < m_numRings; iRing++){
        
        SCT_FwdRing * ring = m_rings[iRing].get();
        
        // Position ring
        double ringZpos = ring->ringSide() * ring->ringOffset();
        double ringOuterZ = ring->ringOffset() +  ring->thicknessOuter();
        maxZOfRingsFront = std::max(maxZOfRingsFront, ringOuterZ);
        
        std::string ringNameTag = "Ring#" + intToString(ring->identifier());
        wheel->add(new GeoNameTag(ringNameTag));
        wheel->add(new GeoIdentifierTag(ring->identifier()));
        wheel->add(new GeoTransform(GeoTrf::Translate3D(0, 0, ringZpos)));
        id.setEtaModule(ring->identifier());
        wheel->add(ring->build(id));
        
        // Position cooling
        // Get a pointer to the cooling ring.
        SCT_FwdRingCooling cooling("RingCoolingW"+intToString(m_iWheel)+"R"+intToString(iRing),
                                   iRing, m_detectorManager, m_geometryManager, m_materials);
        double coolingZpos = ring->ringSide() * (0.5*(m_discSupport->thickness() + cooling.thickness()));
        wheel->add(new GeoTransform(GeoTrf::TranslateZ3D(coolingZpos)));
        wheel->add(cooling.getVolume());
        
        // Power Tapes
        // Get a pointer to the power tape
        SCT_FwdDiscPowerTape powerTape("PowerTapeW"+intToString(m_iWheel)+
                                       "R"+intToString(iRing), iRing,
                                       m_detectorManager, m_geometryManager, m_materials);
        
        double powerTapeZpos = ring->ringSide() * (0.5*(m_discSupport->thickness() + powerTape.thickness()) +
                                                   cooling.thickness());
        // Make sure we don't overlap with powertape from outer rings
        // We store max extent of power tape for each side (Plus, Minus)
        // This is really only ever an issue for ring2 but we keep it general.
        if (ring->ringSide() > 0) {
            double powerTapeZstart = powerTapeZpos -  0.5 * powerTape.thickness();
            if (powerTapeZstart < powerTapeZPlusMax) {
                powerTapeZpos = powerTapeZPlusMax +  0.5 * powerTape.thickness();
            }
            powerTapeZPlusMax = powerTapeZpos +  0.5 * powerTape.thickness();
        } else {
            double powerTapeZstart = powerTapeZpos +  0.5 * powerTape.thickness();
            if (powerTapeZstart > powerTapeZMinusMax) {
                powerTapeZpos = powerTapeZMinusMax -  0.5 * powerTape.thickness();
            }
            powerTapeZMinusMax = powerTapeZpos -  0.5 * powerTape.thickness();
        }
        if ((std::abs(powerTapeZpos)+0.5*powerTape.thickness()) > (std::abs(ringZpos) -  0.5*ring->thicknessInner())) {
            std::cout << "ERROR:  Power tapes clash with modules!!!" << std::endl;
        }
        wheel->add(new GeoTransform(GeoTrf::TranslateZ3D(powerTapeZpos)));
        wheel->add(powerTape.getVolume());
        
        
    } // End Ring loop
    
    
    //
    // Put in the patch Panel
    //
    // Put it on opposide side of outer ring (ring 0).
    int patchPanelSide = m_rotateWheel;
    
    
    // Get outer position of power tape on that side.
    // In case there are no rings on that side (and hence no powertapes) this will be 1/2 disc support thickness
    double powerTapeZMax = 0;
    if (patchPanelSide > 0) {
        powerTapeZMax =  powerTapeZPlusMax;
    } else {
        powerTapeZMax =  -powerTapeZMinusMax;
    }
    
    
    
    // Loop over patch panel locations
    for (int iPPLoc = 0; iPPLoc < m_numPatchPanelLocs ; iPPLoc++) {
        
        // The patchpanels generally repeat in the four quadrants.
        int numRepeat = 1;
        if (m_patchPanelRepeatQuadrant[iPPLoc]) numRepeat = 4;
        int ppType = m_patchPanelType[iPPLoc];
        if (ppType >= m_numPatchPanelTypes) std::cout << "ERROR: Patch Panel type number out of range!" << std::endl;
        for (int iRepeat = 0; iRepeat < numRepeat; iRepeat++) {
            
            // Calculate the location.
            double patchPanelAngle = m_patchPanelLocAngle[iPPLoc] + iRepeat * 90*Gaudi::Units::degree;
            double patchPanelZpos =  patchPanelSide * (powerTapeZMax + 0.5*m_patchPanel[ppType]->thickness() + m_safety);
            double patchPanelR = m_patchPanel[ppType]->midRadius();
            
            // Check for overlap with middle ring.
            if (m_numRings >= 2 && (m_patchPanel[ppType]->innerRadius() <= m_rings[1]->outerRadius())) {
                std::cout << "ERROR: Patch Panel clashes with middle ring" << std::endl;
                std::cout << " PatchPanel inner radius: " << m_patchPanel[ppType]->innerRadius() << std::endl;
                std::cout << " Ring outer radius: " << m_rings[1]->outerRadius() << std::endl;
            }
            
            // Add it to the wheel
            wheel->add(new GeoTransform(GeoTrf::RotateZ3D(patchPanelAngle)*GeoTrf::TranslateX3D(patchPanelR)*GeoTrf::TranslateZ3D(patchPanelZpos)));
            wheel->add(m_patchPanel[ppType]->getVolume());
            
            // Make and add the connector for PPF0e (type 0)
            // Positioned immediately outside PatchPanel at same angle
            if(ppType == 0 && m_pPConnectorPresent) {
                double ppConnectorZpos =  patchPanelSide * (powerTapeZMax + 0.5*m_pPConnector->thickness() + m_safety);
                double ppConnectorR = m_patchPanel[ppType]->outerRadius() + 0.5*m_pPConnector->deltaR() + m_safety;
                // Check is within wheel
                if (ppConnectorR + 0.5*m_pPConnector->deltaR() >= m_outerRadius) {
                    std::cout << "ERROR: Patch Panel Connector clashes outside wheel" << std::endl;
                    std::cout << " PatchPanel Connector outer radius: " << ppConnectorR + 0.5*m_pPConnector->deltaR() << std::endl;
                    std::cout << " Wheel outer radius: " << m_outerRadius << std::endl;
                }
                // Add it to the wheel
                wheel->add(new GeoTransform(GeoTrf::RotateZ3D(patchPanelAngle)*GeoTrf::TranslateX3D(ppConnectorR)*GeoTrf::TranslateZ3D(ppConnectorZpos)));
                wheel->add(m_pPConnector->getVolume());
            }
            
            // Make and add the cooling for PPF0c (type 2)
            // Positioned immediately outside PatchPanel at same angle
            if(ppType == 2 && m_pPCoolingPresent) {
                double ppCoolingZpos =  patchPanelSide * (powerTapeZMax + 0.5*m_pPCooling->thickness() + m_safety);
                double ppCoolingR = m_patchPanel[ppType]->outerRadius() + 0.5*m_pPCooling->deltaR() + m_safety;
                // Check is within wheel
                if (ppCoolingR + 0.5*m_pPCooling->deltaR() >= m_outerRadius) {
                    std::cout << "ERROR: Patch Panel Cooling clashes outside wheel" << std::endl;
                    std::cout << " PatchPanel Cooling outer radius: " << ppCoolingR + 0.5*m_pPCooling->deltaR() << std::endl;
                    std::cout << " Wheel outer radius: " << m_outerRadius << std::endl;
                }
                // Add it to the wheel
                wheel->add(new GeoTransform(GeoTrf::RotateZ3D(patchPanelAngle)*GeoTrf::TranslateX3D(ppCoolingR)*GeoTrf::TranslateZ3D(ppCoolingZpos)));
                wheel->add(m_pPCooling->getVolume());
            }
        }
        
    } // end loop over patch panel locations
    
    
    // Add the optoharness - type depends on number of rings
    // The optoharness is always on the back side (except if the wheel is rotates)
    double optoHarnessZMax = 0.5 * m_discSupport->thickness();
    if (m_optoHarnessPresent) {
        std::string optoharnessName = "OptoHarnessO";
        if(m_numRings > 1) {optoharnessName+="M";}
        if(m_numRings > 2) {optoharnessName+="I";}
        SCT_FwdOptoHarness optoharness(optoharnessName+"W"+intToString(m_iWheel), m_numRings,
                                       m_detectorManager, m_geometryManager, m_materials);
        double optoHarnessZpos = 0.5*m_rotateWheel*(m_discSupport->thickness() + optoharness.thickness());
        wheel->add(new GeoTransform(GeoTrf::TranslateZ3D(optoHarnessZpos)));
        wheel->add(optoharness.getVolume());
        optoHarnessZMax = optoHarnessZpos + 0.5*optoharness.thickness();
    }
    
    // Loop over FSI locations.
    for (unsigned int iFSI = 0; iFSI < m_fsiVector->size(); iFSI++) {
        int type = (*m_fsiVector)[iFSI]->simType();
        double fsiRadius = (*m_fsiVector)[iFSI]->location().radius();
        double fsiPhi    = (*m_fsiVector)[iFSI]->location().phi();
        int fsiUsualSide = (*m_fsiVector)[iFSI]->location().side();
        int fsiSide =   fsiUsualSide * m_rotateWheel;
        double fsiZpos = fsiSide * m_fsiType[type]->zOffset();
        
        // Check for clashes on front side
        if (fsiUsualSide < 0) {
            double zMin =  std::abs(fsiZpos) -  0.5*m_fsiType[type]->thickness();
            if (maxZOfRingsFront > zMin) {
                std::cout << "WARNING: FSI probably clashes with ring" << std::endl;
                std::cout << " maxZOfRingsFront = " << maxZOfRingsFront << std::endl;
                std::cout << " fsiZMin = " << zMin << std::endl;
            }
        } else {   // ... and backside
            // Check radius of fsi.
            // If outer radii check for overlap with powertape
            // If inner radii check for overlap with optoharness (disksupport if no optoharness)
            double diskMidRadius = 0.5*(m_outerRadius + m_innerRadius);
            double servicesZMax = (fsiRadius > diskMidRadius) ? powerTapeZMax : optoHarnessZMax;
            double zMin =  std::abs(fsiZpos) -  0.5*m_fsiType[type]->thickness();
            if (servicesZMax > zMin) {
                std::cout << "WARNING: FSI probably clashes with disc services" << std::endl;
                std::cout << " servicesZMax = " << servicesZMax << std::endl;
                std::cout << " fsiZMin = " << zMin << std::endl;
                std::cout << " fsiRadius = " << fsiRadius << std::endl;
            }
        }
        
        wheel->add(new GeoTransform(GeoTrf::RotateZ3D(fsiPhi)*GeoTrf::TranslateX3D(fsiRadius)*GeoTrf::TranslateZ3D(fsiZpos)));
        wheel->add(m_fsiType[type]->getVolume());
        
        
    } // end loop over FSI.
    
    // Loop over disc fixation locations
    if(m_discFixationPresent) {
        for (unsigned int iLoc = 0; iLoc < m_discFixationLocAngle.size() ; iLoc++) {
            // The disc fixations repeat in the four quadrants.
            for (int iRepeat = 0; iRepeat < 4; iRepeat++) {
                // Calculate the location.
                double discFixationAngle = m_discFixationLocAngle[iLoc] + iRepeat * 90*Gaudi::Units::degree;
                double discFixationR = m_ringMaxRadius + 0.5*m_discFixation->thickness() + m_safety;
                // Check is within wheel
                if (discFixationR + 0.5*m_discFixation->thickness() >= m_outerRadius) {
                    std::cout << "ERROR: Disc Fixation outside wheel" << std::endl;
                    std::cout << "Disc fixation outer radius: " << discFixationR + 0.5*m_discFixation->thickness() << std::endl;
                    std::cout << " Wheel outer radius: " << m_outerRadius << std::endl;
                }
                // Add it to the wheel
                wheel->add(new GeoTransform(GeoTrf::RotateY3D(90.*Gaudi::Units::degree)*GeoTrf::RotateX3D(discFixationAngle)*GeoTrf::TranslateZ3D(discFixationR)));
                wheel->add(m_discFixation->getVolume());
            }
        }
    }
    
    // Extra Material
    InDetDD::ExtraMaterial xMat(m_geometryManager->distortedMatManager());
    xMat.add(wheel, "SCTDisc");
    xMat.add(wheel, "SCTDisc"+intToString(m_iWheel));
    if (m_endcap > 0) {
        xMat.add(wheel, "SCTDiscA");
        xMat.add(wheel, "SCTDiscA"+intToString(m_iWheel));
    } else {
        xMat.add(wheel, "SCTDiscC");
        xMat.add(wheel, "SCTDiscC"+intToString(m_iWheel));
    }
    
    
    
    return wheel;
    
}