1 / 10

Introduction to Irene’s talk (reminder)

Introduction to Irene’s talk (reminder). The 2007 analysis’ scheme (triggered search). 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)

melissa-rosales
Download Presentation

Introduction to Irene’s talk (reminder)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to Irene’s talk (reminder) The 2007 analysis’ scheme (triggered search) 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 The selection criteria follow G. Halladjian’s strategy Optimization for (steady) PS E-2 Unblinding granted before summer 2010 (Referee: Aart Heijboer) Ph. D Thesis of I. Di Palma (AEI) Coincidence window  500s  GWHEN group, Astropart. Phys. 35 (2011) 1-7

  2. Data and MC samples Data sample • The coincident period of 5L/S5/VSR1 is between January 27th and September 30th, 2007 • lifetime of the selected data sample: 103.281 days (37.8 days for 10pe and 65.5 days for 3pe high threshold) MC sample • Atmospheric neutrinos : • Simulation package: Genhen, weight : Bartol flux • energy range between 10 GeV and 107 GeV • Atmospheric muons: • Simulation package : Corsika, weight : Battistoni’s parameterization • Cosmic neutrinos : • Simulation package: Genhen • weighted with a E-2 energy spectrum • Data and MC sample are reconstructed with the BBfit reconstruction package (v3r6)

  3. Reconstruction used Track 1 Detector line ● Two possible tracks (Mirror solution) ● Track 2 ● ● ● ● Two possible azimuth values (Same zenith) == Due to simplified detector geometry == • Events reconstructed with 2 lines • 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  Better angular accuracy than if taking random track solution  Smaller search box for GW detectors

  4. Cut optimization Cut are applied to maximize the discovery potential in search for E-2 point sources Only up-going events are considered. Method : test statistics LR to get optimum nsig Different values of track and bright point c2 for different zenith angles are tested 70 possible combinations  G. Halladjian, Ph. D, University Marseilles, Dec 2010

  5. Chosen cuts (up-going events) • bc2 >2.2 (reduced contamination of • atmospheric muons) • tc2 <=1.8 for zenith<80° • tc2 <=1.4 for 80°<zenith<90° • 20% contamination from atmospheric • muons for 80°<zenith<90° for zenith<80°

  6. Angular search window μ β 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 • Log-normal (instead of Fisher) distributions are fitted and provided for processing with X-pipeline (weight the scan directions inside the angular window) 90% quantile nhit=7 θ is the location parameter σ is the shape parameter m is the scale parameter

  7. 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 )

  8. Spare

  9. Coincidence window  GWHEN group, Astropart. Phys. 35 (2011) 1-7 Precursor Upper bound for BATSE Collapsar model Time to break out envelope Opaque to g’s Based on BATSE T90’s And FERMI-LAT data  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.  Precursors were observed for ~15% of GRBs (long and short (8%)) Emission mechanisms might be that of prompt GRBs same model

  10. Angular search window μ β 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

More Related