Validation of the ALICE material budget between TPC and TOF detectors

This note presents a method to validate the material budget of the ALICE apparatus located at midrapidity between the Time Projection Chamber (TPC) and the Time-of-Flight (TOF) detector. The analysis is performed in p$-$Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV using pure samples of protons from $\Lambda \rightarrow \rm{p} + \pi^{-}$ decays and pions from $\rm{K}^{0}_{\rm S} \rightarrow \pi^{+} + \pi^{-}$ decays which are reconstructed with the Inner Tracking System (ITS) and TPC. The TOF$-$TPC matching efficiency (i.e. the ratio between the number of hadrons with a matched hit in the TOF to those reconstructed in the TPC) is investigated for pions and protons as a function of the momentum at the TPC inner radius $p_{\rm TPC}$. The results are compared with detailed Monte Carlo simulations based on GEANT3 and GEANT4 transport codes used for propagation of particles through the ALICE apparatus. As a result, the material budget between TPC and TOF is validated using protons and pions in the momentum interval of $0.5 < p_{\rm TPC} < 5.0$ GeV/$c$ with a precision of $\lesssim 5\%$.