Photonics WorkshopAMANDA/IceCube Collaboration Meeting

Berkeley, March 19, 2005

Going the last mile…

Photonics Workshop, Berkeley, March 19, 2005

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

Ice Model Basics

• Need to describe photon(A,t) around light sources (muon tracks, cascades) for simulations of AMANDA events

• Tables of photon(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

power-law for dust

flat for bubbles

bu

bb

les

scattering by dust

Photonics Workshop, Berkeley, March 19, 2005

Light Absorption in South Pole ice

absorption follows dust profile

flat (weak temp. dependence)

absorptionby ice

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

photonicsBulk PTD Layered PTD

PTD vs. photonics: layering

average ice type 1 type 2 type 3 “real” ice

3

3

3

1

1

2

2

2

2

2

2

Photonics Workshop, Berkeley, March 19, 2005

PTD-based ice models

MAM, mamintasens16-layer“Kurt”, stdkurt, sudkurtbulkkgmf125

See talk on ice models at Madison AMANDA meeting in 2003 for details

Photonics Workshop, Berkeley, March 19, 2005

We’re getting there…

Photonics Workshop, Berkeley, March 19, 2005

frozen subglacial lake

airborne radar imaging (Blankenship et al.)

South Pole stationand AMANDA

IceCube

For IceCube:Are the dust layers horizontal

on km-scale?

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)