Neutrino Point Source Searches with AMANDAII mDAQ

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Neutrino Point Source Searches with AMANDA-II
m-DAQ

• Jim Braun

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m-DAQ Point Source Searches
Would like to combine all years into a reasonably
unified final event sample and publish point
source result in early 2008 Sample will also be
used by John K. and others
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Data Filtering

• Two main data sets
• 2000-2004 Filtered to L3 (1G events ? 1M
  events) with Zeuthen scheme
• 2005-2006 Filtered to L3 with UW scheme
• Zeuthen and UW filtering very similar
• Do not need to refilter to achieve a reasonably
  uniform event sample

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Final Event Sample

• Final event samples are significantly different!

• Zuethen 2000-2004
• Strong likelihood difference cut (downgoing vs.
  unconstrained)
• Strong P_hit smoothness cut
• Strong paraboloid error cut
• 1K events/year
• High Purity
  

• UW 2005-2006
• Weaker likelihood difference cut at horizon
• Weaker P_hit smoothness cut
• Strong paraboloid error cut
• Weak direct length cut
• Maximum sensitivity near horizon

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Event Selection

• Need a uniform event selection for all years
• Non-uniform selection is confusing
• Non-uniform selection would tend to combine the
  undesirable properties of both selections
• Choose Zeuthen cuts for final event sample
• Match 2000-2004 publication
• 91 of events from 2005-2006 with Zeuthen cuts
  are already contained in UW sample

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Final Event Sample
6166 Total events in final sample
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Normalization

• Data normalized to average of Barr et al. and
  Honda 2006 model atmospheric neutrino predictions
• Corrects for uncertainties in MC
• (e.g. ice properties, OM sensitivity)
• Final normalization 0.901
• ? Ratio of starting/final normalization indicates
  sample is 97 pure

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Final Sample
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Final Sample