IceCube Construction and Analysis Report

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IceCube Construction and Analysis Report

• Martijn Duvoort
• Sterrekundig Instituut Utrecht
• Faculty of Science, Department of Physics and
  Astronomy, University of Utrecht
• Princetonplein 5, NL-3584 CC Utrecht, The
  Netherlands M.R.Duvoort_at_phys.uu.nl
  http//www.phys.uu.nl/duvoort

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Neutrino Astronomy
Cosmic accelerator
1 pc 3 ly 1018 cm
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Introducing IceCube
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IceCube
IceTop
total of 40 Strings IceCube 0.5 km3 AMANDA
0.016 km3
Air shower detetor threshold 300 TeV
InIce
first data 2005 upgoing muon 18. Juli 2005
70-80 Strings , 60 Optical Modules 17 m between
Modules 125 m between Strings
AMANDA 19 Strings 677 Modules
Three more deployment seasons to finish in 2011
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IceCube 40

• First km-scale detector
• 31 times AMANDA
• Fully digital waveforms
• In-ice timing calibration
• 0.5 - 1 degree resolution
• (depending on track length)
• Data since March 2008

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IC22 Events
( Red hits early yellow/green/blue later )
IceCube DOM locations blue, AMANDA OM locations
red
Downward cosmic-ray event (muon bundle)
Upward candidate n event
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IceCube extensions Deep Core

• IceCube DOM technology
• AMANDA has no veto coverage from top, (which is
  where the muons come from)
• Ice below 2100m is exceptionally clear,
  significantly better even than current ice model.
  
• Swedish proposal funded by Wallenberg Foundation

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Current GRB analyses

• ? - ? coincident analysis per GRB
• Fails in case of time difference
• Rolling time window
• Needs GRB with multiple ? detections
• Only 1 10 of GRBs will induce signal ?
• Halzen Hooper 1999, Astrophys. J. 527 (1999)
  L93
• Need new method
• Should cope with time difference
• Should allow for cumulative statistics

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Stacking
? data
Need to cut the background!
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Stacking around the GRB

• Bkg suppression by GRB location
• 5 deg area around GRB position
• 0.5 1 deg resolution ? cut bkg keep signal
• Used 100 GRBs
• background determination ? off-time sample

Signal Background
On-source
Background
Off-time
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Sensitivity of our method

• Parameters determining sensitivity
• Number of bursts in sample
• Fraction f of GRBs which yield a signal ?
• Detection in case of 5 s effect
• Minimal f as function of GRBs for detection
• Swift and GLAST nicely coincide with IceCube

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Conclusion
Astropart. Phys 28 (2008) 540
f the fraction of GRBs inducing a signal ?

• 1 km3 ? detector discovery in coming year(s)

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Current Status

• Data reconstruction
• 4 years of full AMANDA data
• 2 years of IceCube data
• Off-time bkg determination in process
• (blind) sample used to settle final analysis cuts
• Unblinding proposal expected this spring
• Run final analysis on unblinded sample