IceCube: initial performance

1
IceCube initial performance

• Deployment during austral summer 04-05
• Reconstruction of digital waveforms
• Time calibration
• Detector verification with flashers
• Muon reconstruction
• Timing verification with muons
• Coincident muon IceTop shower events

Dmitry Chirkin, LBNL
for the IceCube collaboration
2
IceCube introduction

• Deep ice array IceCube
• Digital readout technology
• 80 strings / 60 DOMs each
• 17 m DOM spacing
• 125 m between strings
• hexagonal pattern over 1 km2x1 km

3
The first muon IceTop shower coincident event
January 23 First runs with the four IceTop
stations (8 tanks) taken January 29 131 NZT
First IceCube string deployed February 9 First
shower/muon coincidence events found
4
Waveform pulse reconstruction
5
Time Calibration
6
Timing verification with flashers
7
IceCube muon data reconstruction
8
Muon time calibration verification

• reconstruct muon tracks without DOM X
• plot the time residual for DOM X for nearby
  reconstructed tracks
• if scattering length is longer than the distance
  cut (10 m) the most likely residual should be 0,
  otherwise residual will show delay increasing
  with the amount of scattering.

9
IceTop and in-ice coincidences
10
Summary

• The first IceCube string and four IceTop
  stations were deployed last austral summer
  analysis began after freeze-in.
• The ability to reconstruct muons and air
  showers, and to detect muons coincident with air
  showers was demonstrated
• The observed muon flux is consistent with the
  expectation from the simulation
• The overall detector timing uncertainty was
  measured to be below 3 ns
• The first elements of the IceCube detector
  perform as expected, or better.
• Deployment of up to 10 IceCube strings and 20
  IceTop tanks is scheduled for the coming season.

11
Reconstruction of the simulated data