Michels and Muons Calibration 
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This is a simulation based on Geant4. We are looking for the response of a LAr detector due to the injection of muons. Moreover, we identify the creation of the Michel electron, where we will retrieve the vertex information. 


 1) GEOMETRY
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Dimensions are based on G4CCMDetectorConstruction implemented in the CCMAnalysis (excluding the CWs and shielding).

- Outer and Inner Cryostat.

- reflector foils coated with TPB that separate the veto Active and active volume, 

- Active volume: It is cylinder filled with LAr. It is the inner SD where will capture the hits associated with the primary secondary particles result from the injection of muons as well identify the Michel creation.    

- Veto: It is a SD cylinder filled with LAr. Envolve the active volume, and registered also depositions of energy. 

- Cosmic Watchers (CWs): there are six prisms of poly their mission is to constraint the directions in which the Michel is created. 

- Shielding: It is an arrange of concrete and steel blocks that surrounded the CCM detector. 


2) GENERATOR
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 - Muons are generated from a geometrical construction. Muons are created on a tangent plane (4m length) of a spherical hemisphere (radius 16m). We use MC random numbers generator that follow the Smith-Duller parametrization and the angular distribution follow the profile cos^{2}.

 - To the Michel analysis, we must include an additional constraint in the injection of muons, that is, muons are created such that go through any of the six pairs of CWs arange on the outer cryostat. We assume that the muons travel in a straight line from the point where is created to the center of each CWs, only are accepted muons that deposited energy both the top and bottom CW in each pair. 


3) EVENT
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- Event is the information retrieved from the collection of hits from the SDs, the vertex information of the primary particles as well as the identification of the Michel. After the extraction of the information we will fill the histograms that compose the tree saved in the .root files. 

 In the tree we can identify the MUON INFORMATION which contain the vertex information of the primary muon, the deposited energy of the muons as their secondaries both in the veto and the inner volume, and the length traced by the muons in the active volume. Moreover, the tree identify the MICHEL INFORMATION which contain the deposited energy of the michel, and the vertex information (position, energy, direction)     

4) DETECTOR RESPONSE
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All the information to simulate and analyse that will define the Event is recorded in the hits, step and track information.

 ---- SD active volume
      --- LArSD: pass the information that will be recorded in the hits collection: deposited energy, hit position, particle name, creator process, parentID of muons as well their secondaries.

 ----- SD veto 
      --- VetoSD: record the same information of the LArSD class. 

 ---- SD CWs
      --- CWSD: This record the deposited energy of the muons that go through the top and bottom CWs in each pair. In the same class is saved the histograms.  

 ---- Tracking Action
     --- identify the track associated with the creation of a Michel. We use a threshold of 1 MeV due to the decay in orbit of muon minus is a competitive process with the nuclear capture, then below of this energy should correspond only with cascade electrons (in the order of KeV).
 
 ---- Stepping Action
     --- call the information of Tracking action and retrieve the information associated to the step of the Michel. Here we recover the vertex kinetic energy, the step length and the vertex position of the Michel. This information is pass to the Event class. 
  
5) ANALYSIS
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In the run action class is created two Ntuples, one is associated to the level of hits (VetoSD and LArSD) and the other is relate to the Event. All the Ntuples are saved in two output files in a root file format.

6) Processes 

PhysicsList::HadronElasticPhysicsHP
|---- High precision on neutron processes 

PhysicsList::G4HadronElasticPhysics
|---- All hadron elastic models

PhysicsList::G4IonPhysics
|-----Interactions with ions
  |___ Elastic/inelastic nuclear reactions 

PhysicsList::PhysListEmStandard
|---gamma
   |____G4RayleighScattering, G4PhotoElectricEffect, G4ComptonScattering, G4GammaConversion
|---electron
   |____G4eMultipleScattering()
   |____G4eIonisation()
   |____G4eBremsstrahlung()
|---mu+ or mu- 
   |_____G4MuMultipleScattering()
   |_____G4MuIonisation()
   |_____G4MuBremsstrahlung()
   |_____G4MuPairProduction()
|---proton or pion + or pion - 
   |_____G4hMultipleScattering()
   |_____ G4hIonisation()
   |_____G4hBremsstrahlung()
   |_____G4hPairProduction()
   
PhysicsList::G4StoppingPhysics
|-- handle the atomic capture mainly included to the muon minus capture.

PhysicsList::DecayPhysicsList
   
Particles
│
├── Leptons (e⁻, μ⁻, τ⁻)
│    └─ EM interactions (ionization, bremsstrahlung) [PhysListEmStandard]
│    └─ Decay (muon, tau) [G4DecayPhysics]
│
├── Hadrons (proton, neutron, pion, kaon)
│    └─ EM interactions (ionization) [PhysListEmStandard]
│    └─ Hadronic inelastic (e.g., pion absorption) 
│    └─ Decay (pion decay, kaon decay) [G4DecayPhysics]
│
└── Ions (alpha, C, Fe, U nuclei)
     └─ Elastic/inelastic nuclear reactions [G4IonPhysics]
     └─ Radioactive decay (beta, alpha, fission) [G4RadioactiveDecayPhysics]


7) Compilation 

for the compilation we just set in the terminal window
./build/simlar run1.mac 
assumming that the compilation is executing outside the build directory. the run1.mac is the macro that handle the logic of the simulation, it will depend if we just want to retrieve the Muon analysis or the Michel analysis.