Photonics Workshop AMANDA/IceCube Collaboration Meeting Berkeley, March 19, 2005 Going the last mile…

Photonics Workshop Objectives Review where we stand - Debugging/testing complete? - Do we have all the tools we need? Coordinate how we proceed - Final go for mass production Photonics in IceCube - Do we have a plan? If not, make one Photonics Workshop, Berkeley, March 19, 2005

Photonics Workshop Agenda Introduction Kurt Woschnagg 10’ Status of photonics development Johan Lundberg 45’ Update on PSI Thomas Burgess 10’ New features Michelangelo D’Agostino 15’ Photonics with simuperl Markus Ackermann 10’ Wuppertal photonics production Christopher Wiebusch 10’ Discussion All 60’ Merging with Simulation Workshop Photonics Workshop, Berkeley, March 19, 2005

Photonics Workshop, Berkeley, March 19, 2005 Ice Model Basics Need to describe Fphoton(A,t) around light sources (muon tracks, cascades) for simulations of AMANDA events Tables of Fphoton(A,t) are calculated using Monte Carlo propagation of photons through scattering and absorbing medium (ice) Dependence on distance, OM orientation, ice properties, etc Prefer to have simplifications (symmetries, averages, approximations) but must pay price for these Photonics Workshop, Berkeley, March 19, 2005

Light Scattering in South Pole ice flat for bubbles bubbles power-law for dust scattering by dust Photonics Workshop, Berkeley, March 19, 2005

Light Absorption in South Pole ice flat (weak temp. dependence) absorption by ice absorption follows dust profile Photonics Workshop, Berkeley, March 19, 2005

Light propagation codes: two approaches PTD Photons propagated through ice with homogeneous prop. Uses average scattering No intrinsic layering: each OM sees homogeneous ice, different OMs may see different ice Fewer tables Faster Approximations Photonics Photons propagated through ice with varying properties All wavelength dependencies included Layering of ice itself: each OM sees real ice layers More tables Slower Detailed Photonics Workshop, Berkeley, March 19, 2005

Photonics Workshop, Berkeley, March 19, 2005 PTD vs. photonics: layering Bulk PTD Layered PTD photonics 2 3 2 1 2 3 2 1 2 3 2 average ice type 1 type 2 type 3 “real” ice Photonics Workshop, Berkeley, March 19, 2005

Photonics Workshop, Berkeley, March 19, 2005 PTD-based ice models MAM, mamint asens 16-layer “Kurt”, stdkurt, sudkurt bulk kgm f125 See talk on ice models at Madison AMANDA meeting in 2003 for details Photonics Workshop, Berkeley, March 19, 2005

Photonics Workshop, Berkeley, March 19, 2005 We’re getting there… Photonics Workshop, Berkeley, March 19, 2005

airborne radar imaging South Pole station and AMANDA airborne radar imaging (Blankenship et al.) For IceCube: Are the dust layers horizontal on km-scale? The flat radar profile in lower left indicates a subglacial lake ~8 km from South Pole at depth 2.8 km. It was once liquid and may still contain microbial life in a permafrost layer. It is hydraulically isolated. It is a mix of sediment and ice. IceCube frozen subglacial lake Photonics Workshop, Berkeley, March 19, 2005

Photonics Workshop, Berkeley, March 19, 2005 Discussion Topics Table production: what, where, when Systematics (special tables) Special sources Table fitting Do we still have a size/memory problem? NN fits IceCube L4? Special needs: Extended ice table DOM description Future complications Non-horizontal dust layers (breaking the last symmetry) Photonics Workshop, Berkeley, March 19, 2005