Muon-induced neutral particle background for a shallow depth Iron Calorimeter detector

The 51 kton Iron Calorimeter (ICAL) detector for measuring atmospheric muon neutrinos and muon anti-neutrinos separately will enable addressing the neutrino mass hierarchy problem. This will be the flagship experiment at the India based Neutrino Observatory (INO) and will be located in a cavern in a mountain with a rock cover of 1 km in all directions. This will help reduce the cosmic muon background by a factor of 106 with respect to that at sea level. In this work, the possibility of a 100 m shallow depth ICAL (SICAL) is explored. To achieve a similar cosmic muon background reduction as at 1 km depth a cosmic muon veto detector (CMVD) which can reject muons with an efficiency of 99.99% is required. However an important background could be neutral long lived particles such as neutrons and K0L produced in interactions of muons with rock closest to ICAL. The charged particles produced in muon-nuclear interactions can be vetoed but the neutral particle can pass through CMVD undetected and subsequently mimic a neutrino like event in ICAL In this contribution the results of a GEANT4 based simulation to estimate this background in SICAL are presented.