Download - Introduction to Irene’s talk (reminder)
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Introduction to Irene’s talk (reminder)
Coincidence window 500s GWHEN group, Astropart. Phys. 35 (2011) 1-7
Ph. D Thesis of I. Di Palma (AEI)
Ph. D Thesis of B. Bouhou (APC) Updates on this work:
- 17 May - 20 May Clermont-Ferrand meeting (2010)
- 20 Sep - 24 Sep Paris meeting (2010)
- 22 Nov - 25 Nov Amsterdam meeting (2010)
- 07 Feb - 10 Feb CERN meeting (2011)
- 06 Jun - 10 Jun Moscow meeting (2011)
Internal note: ANTARES-PHYS-2011-003
wiki page:
http://antares.in2p3.fr/internal/dokuwiki/doku.php?id=link
Updates on this work:
- 17 May - 20 May Clermont-Ferrand meeting (2010)
- 20 Sep - 24 Sep Paris meeting (2010)
- 22 Nov - 25 Nov Amsterdam meeting (2010)
- 07 Feb - 10 Feb CERN meeting (2011)
- 06 Jun - 10 Jun Moscow meeting (2011)
Internal note: ANTARES-PHYS-2011-003
wiki page:
http://antares.in2p3.fr/internal/dokuwiki/doku.php?id=link
The selection criteria followG. Halladjian’s strategy
Optimization for (steady) PS E-2
Unblinding granted before summer 2010(Referee: Aart Heijboer)
The 2007 analysis’ scheme (triggered search)The 2007 analysis’ scheme (triggered search)
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Data and MC samples
lifetime of the selected data sample: 103.281 days (37.8 days for 10pe and 65.5 days for 3pe high threshold)
Data sample The coincident period of 5L/S5/VSR1 is between January 27th and September 30th, 2007
Simulation package: Genhen, weight : Bartol flux
energy range between 10 GeV and 107 GeV
Simulation package : Corsika, weight : Battistoni’s parameterization
Atmospheric neutrinos :
Atmospheric muons:
Simulation package: Genhen
weighted with a E-2 energy spectrum
Data and MC sample are reconstructed with the BBfit reconstruction package (v3r6)
Cosmic neutrinos :
MC sample
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Better angular accuracy than if taking random track solution Smaller search box for GW detectors
Two possible tracks(Mirror solution)
Two possible azimuth values (Same zenith)
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Track 1
Track 2
Detector line
Reconstruction used
• Events reconstructed with 2 lines
== Due to simplified detector geometry ==
• The version of the reconstruction offers the possibility to get the azimuth of the mirror solution in the case of events reconstructed with two lines
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Cut optimizationCut are applied to maximize the discovery potential in search for E-2 point sourcesOnly up-going events are considered.Method : test statistics LR to get optimum nsig
Different values of track and bright point 2 for different zenith angles are tested 70 possible combinations
G. Halladjian, Ph. D, University Marseilles, Dec 2010
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Chosen cuts (up-going events)• b2 >2.2 (reduced contamination ofatmospheric muons)• t2 <=1.8 for zenith<80° • t2 <=1.4 for 80°<zenith<90°
• 20% contamination from atmosphericmuons
for zenith<80°
for 80°<zenith<90°
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Angular search window
βμ
ν
The space angle β between the true neutrino direction and the reconstructed muon direction (E-2 spectrum) defines the angular accuracy
The angular search window is defined as 50% quantile ( or 90% quantile ) of the β distribution in bins of reconstructed declination (10°) and number of hits
90% quantile
nhit=7
Log-normal (instead of Fisher) distributions are fitted and provided for processing with X-pipeline (weight the scan directions inside the angular window)
θ is the location parameter
m is the scale parameterσ is the shape parameter
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The HEN candidate list time Dec(°) RA (°) lines hits ASW(50%) ASW(90%) weight
….
….
• 18 events reconstructed with 3 lines and more.• 198 events reconstructed with exactly two lines : 2 solutions• Total number of events ( 18 + 2*198 )
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Spare
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Coincidence window
Fig. 1. (a) active central engine before the relativistic jet has broken out of the stellar envelope; (b) active central engine with the relativistic jet broken out of the envelope; (c) delay between the onset of the precursor and the main burst; (d) duration corresponding to 90% of GeV photon emission; (e) time span of central engine activity.
Based on BATSE T90’sAnd FERMI-LAT data
Collapsar modelTime to break out envelope
Opaque to ’s
Precursors were observed for ~15% of GRBs (long and short (8%)) Emission mechanisms might be that of prompt GRBs same model
PrecursorUpper bound for BATSE
GWHEN group, Astropart. Phys. 35 (2011) 1-7
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Angular search window
βμ
ν
The error β on the neutrino direction is defined as the angular difference between the true neutrino direction and the reconstructed muon direction (E-2 spectrum)
The angular search window is defined as 50% quantile ( or 90% quantile ) of the β distribution in bins of reconstructed declination (10°) and number of hits
ASW 50% ASW 90% used for GW+HEN search