Light tracking for glaciers and oceans – Scattering and absorption in heterogeneous media with PHOTONICS

In the field of neutrino astronomy, glacial ice or deep ocean water are used as detector medium. Elementary particle interactions are studied using in situ detectors recording time distributions and fluxes of the faint photon fields of Cherenkov radiation, typically generated by ultra-relativistic muons. The Photonics software package was developed to determine photon flux and time distributions throughout a volume through Monte Carlo simulation. Photons are propagated and time distributions are recorded throughout a cellular grid constituting the simulation volume, and the Mie scattering is realized using wavelength and position dependent parameterisations. The photon tracking results are stored for transparent access through ansi-c and c++ interfaces. In this paper the Photonics light propagation routines and methodology are introduced and applied to the IceCube and Antares neutrino telescopes. The way in which inhomogeneities of the Antarctic glacial ice distort the signatures of elementary particle interactions, and how Photonics can be used to account for these effects, is described.