[ALICE3] Add Copper stabilizers for A3 Magnet

Detectors/Upgrades/ALICE3/Passive/CMakeLists.txt

@@ -12,13 +12,15 @@
 o2_add_library(Alice3DetectorsPassive
                SOURCES src/Pipe.cxx
                        src/PassiveBase.cxx
+                       src/PassiveBaseParam.cxx
                        src/Absorber.cxx
                        src/Magnet.cxx
                PUBLIC_LINK_LIBRARIES O2::Field O2::DetectorsBase O2::SimConfig)
 
 o2_target_root_dictionary(Alice3DetectorsPassive
                           HEADERS include/Alice3DetectorsPassive/Pipe.h
                                   include/Alice3DetectorsPassive/PassiveBase.h
+                                  include/Alice3DetectorsPassive/PassiveBaseParam.h
                                   include/Alice3DetectorsPassive/Absorber.h
                                   include/Alice3DetectorsPassive/Magnet.h
                           LINKDEF src/PassiveLinkDef.h)

Detectors/Upgrades/ALICE3/Passive/include/Alice3DetectorsPassive/PassiveBaseParam.h

@@ -0,0 +1,43 @@
+// Copyright 2019-2020 CERN and copyright holders of ALICE O2.
+// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
+// All rights not expressly granted are reserved.
+//
+// This software is distributed under the terms of the GNU General Public
+// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#ifndef ALICEO2_PASSIVE_BASEPARAM_H_
+#define ALICEO2_PASSIVE_BASEPARAM_H_
+
+#include "CommonUtils/ConfigurableParam.h"
+#include "CommonUtils/ConfigurableParamHelper.h"
+
+namespace o2
+{
+namespace passive
+{
+
+// **
+// ** Parameters for Passive base configuration
+// **
+
+enum MagnetLayout : int {
+  AluminiumStabilizer = 0,
+  CopperStabilizer = 1
+};
+
+struct Alice3PassiveBaseParam : public o2::conf::ConfigurableParamHelper<Alice3PassiveBaseParam> {
+  // Geometry Builder parameters
+
+  int mLayout = MagnetLayout::AluminiumStabilizer;
+
+  O2ParamDef(Alice3PassiveBaseParam, "Alice3PassiveBase");
+};
+
+} // namespace passive
+} // end namespace o2
+
+#endif // ALICEO2_PASSIVE_BASEPARAM_H_

Detectors/Upgrades/ALICE3/Passive/src/Magnet.cxx

@@ -12,6 +12,7 @@
 #include <DetectorsBase/Detector.h>
 #include <DetectorsBase/MaterialManager.h>
 #include <Alice3DetectorsPassive/Magnet.h>
+#include <Alice3DetectorsPassive/PassiveBaseParam.h>
 #include <TGeoCompositeShape.h>
 #include <TGeoManager.h>
 #include <TGeoMatrix.h>
@@ -54,11 +55,24 @@ void Alice3Magnet::createMaterials()
   // | Support cylinder |           20            |  8.896   | 0.225  |
   // | Al-strip         |            1            |  8.896   | 0.011  |
   // | NbTi/Cu          |            3            |  1.598   | 0.188  |
-  // | Insulation       |           11            | 17.64    | 0.062  |
+  // | Insulation       |           11            |  17.64   | 0.062  |
   // | Al-stabiliser    |           33            |  8.896   | 0.371  |
   // | Inner cryostat   |           10            |  8.896   | 0.112  |
   // | Outer cryostat   |           30            |  8.896   | 0.337  |
   // +------------------+-------------------------+----------+--------+
+  // Update: 2025-06-16 enabledby setting Alice3PassiveBase.mLayout=1
+  // +------------------+-------------------------+----------+--------+
+  // |  layer           | effective thickness [mm]|  X0 [cm] | X0 [%] |
+  // +------------------+-------------------------+----------+--------+
+  // | Support cylinder |           20            | 8.896 | 0.225     |
+  // | Al-strip         |            1            | 8.896 | 0.011     |
+  // | NbTi/Cu          |            3            | 1.598 | 0.188     |
+  // | Insulation       |           11            | 17.64 | 0.062     |
+  // | Cu-stabiliser    |           22            | 1.436 | 1.532     |
+  // | Inner cryostat   |           10            | 8.896 | 0.112     |
+  // | Outer cryostat   |           30            | 8.896 | 0.337     |
+  // | total            |                         |       | 2.468     |
+  // +------------------+-------------------------+----------+--------+
   // Geometry will be oversimplified in two wrapping cylindrical Al layers (symmetric for the time being) with a Copper layer in between.
 
   //
@@ -90,6 +104,15 @@ void Alice3Magnet::ConstructGeometry()
 {
   createMaterials();
 
+  // Passive Base configuration parameters
+  auto& passiveBaseParam = Alice3PassiveBaseParam::Instance();
+  const bool doCopperStabilizer = (passiveBaseParam.mLayout == o2::passive::MagnetLayout::CopperStabilizer);
+  if (doCopperStabilizer) {
+    mRestMaterialThickness -= 3.3; // cm Remove the Aluminium stabiliser
+    mRestMaterialThickness += 2.2; // cm Add the Copper stabiliser
+    LOG(debug) << "Alice 3 magnet: using Copper Stabilizer with thickness " << mRestMaterialThickness << " cm";
+  }
+
   TGeoManager* geoManager = gGeoManager;
   TGeoVolume* barrel = geoManager->GetVolume("barrel");
   if (!barrel) {
@@ -102,22 +125,22 @@ void Alice3Magnet::ConstructGeometry()
   auto kMedVac = matmgr.getTGeoMedium("ALICE3_MAGNET_VACUUM");
 
   // inner wrap
-  LOGP(debug, "Alice 3 magnet: creating inner wrap with inner radius {} and thickness {}", mInnerWrapInnerRadius, mInnerWrapThickness);
+  LOGP(debug, "Alice 3 magnet: creating inner wrap with inner radius {} cm and thickness {} cm", mInnerWrapInnerRadius, mInnerWrapThickness);
   TGeoTube* innerLayer = new TGeoTube(mInnerWrapInnerRadius, mInnerWrapInnerRadius + mInnerWrapThickness, mZLength / 2);
   TGeoTube* innerVacuum = new TGeoTube(mInnerWrapInnerRadius + mInnerWrapThickness, mCoilInnerRadius, mZLength / 2);
   // coils layer
-  LOGP(debug, "Alice 3 magnet: creating coils layer with inner radius {} and thickness {}", mCoilInnerRadius, mCoilThickness);
+  LOGP(debug, "Alice 3 magnet: creating coils layer with inner radius {} cm and thickness {} cm", mCoilInnerRadius, mCoilThickness);
   TGeoTube* coilsLayer = new TGeoTube(mCoilInnerRadius, mCoilInnerRadius + mCoilThickness, mZLength / 2);
   TGeoTube* restMaterial = new TGeoTube(mRestMaterialRadius, mRestMaterialRadius + mRestMaterialThickness, mZLength / 2);
   TGeoTube* outerVacuum = new TGeoTube(mRestMaterialRadius + mRestMaterialThickness, mOuterWrapInnerRadius, mZLength / 2);
   // outer wrap
-  LOGP(debug, "Alice 3 magnet: creating outer wrap with inner radius {} and thickness {}", mOuterWrapInnerRadius, mOuterWrapThickness);
+  LOGP(debug, "Alice 3 magnet: creating outer wrap with inner radius {} cm and thickness {} cm", mOuterWrapInnerRadius, mOuterWrapThickness);
   TGeoTube* outerLayer = new TGeoTube(mOuterWrapInnerRadius, mOuterWrapInnerRadius + mOuterWrapThickness, mZLength / 2);
 
   TGeoVolume* innerWrapVol = new TGeoVolume("innerWrap", innerLayer, kMedAl);
   TGeoVolume* innerVacuumVol = new TGeoVolume("innerVacuum", innerVacuum, kMedVac);
   TGeoVolume* coilsVol = new TGeoVolume("coils", coilsLayer, kMedCu);
-  TGeoVolume* restMaterialVol = new TGeoVolume("restMaterial", restMaterial, kMedAl);
+  TGeoVolume* restMaterialVol = new TGeoVolume("restMaterial", restMaterial, doCopperStabilizer ? kMedCu : kMedAl);
   TGeoVolume* outerVacuumVol = new TGeoVolume("outerVacuum", outerVacuum, kMedVac);
   TGeoVolume* outerWrapVol = new TGeoVolume("outerWrap", outerLayer, kMedAl);
 

Detectors/Upgrades/ALICE3/Passive/src/PassiveBaseParam.cxx

@@ -0,0 +1,13 @@
+// Copyright 2019-2020 CERN and copyright holders of ALICE O2.
+// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
+// All rights not expressly granted are reserved.
+//
+// This software is distributed under the terms of the GNU General Public
+// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#include "Alice3DetectorsPassive/PassiveBaseParam.h"
+O2ParamImpl(o2::passive::Alice3PassiveBaseParam);

Detectors/Upgrades/ALICE3/Passive/src/PassiveLinkDef.h

@@ -16,6 +16,7 @@
 #pragma link off all functions;
 
 #pragma link C++ class o2::passive::Alice3PassiveBase + ;
+#pragma link C++ class o2::passive::Alice3PassiveBaseParam + ;
 #pragma link C++ class o2::passive::Alice3Pipe + ;
 #pragma link C++ class o2::passive::Alice3Absorber + ;
 #pragma link C++ class o2::passive::Alice3Magnet + ;