  The magnetized Iron CALorimeter detector (ICAL) which is proposed to be built
in the India-based Neutrino Observatory (INO) laboratory, aims to study
atmospheric neutrino oscillations primarily through charged current
interactions of muon neutrinos and anti-neutrinos with the detector. The
response of muons and charge identification efficiency, angle and energy
resolution as a function of muon momentum and direction are studied from
GEANT4-based simulations in the peripheral regions of the detector. This
completes the characterisation of ICAL with respect to muons over the entire
detector and has implications for the sensitivity of ICAL to the oscillation
parameters and mass hierarchy compared to the studies where only the
resolutions and efficiencies of the central region of ICAL were assumed for the
entire detector.
  Selection criteria for track reconstruction in the peripheral region of the
detector were determined from the detector response. On applying these, for the
1--20 GeV energy region of interest for mass hierarchy studies, an average
angle-dependent momentum resolution of 15--24%, reconstruction efficiency of
about 60--70% and a correct charge identification of about 97% of the
reconstructed muons were obtained. In addition, muon response at higher
energies upto 50 GeV was studied as relevant for understanding the response to
so-called rock muons and cosmic ray muons. An angular resolution of better than
a degree for muon energies greater than 4 GeV was obtained in the peripheral
regions, which is the same as that in the central region.
