const Int_t kNsect = 18; // Number of sectors in the full detector
const Int_t kNplan = 6; // Number of planes of the TRD
const Int_t kNcham = 5; // Number of chambers in z-direction
+const Int_t kNdet = kNsect * kNplan * kNcham;
const Float_t kRmin = 294.0; // r-dimensions of the TRD
const Float_t kRmax = 368.0;