POINT SOURCE ANALYSIS WITH 5-LINE DATA SUMMARY AWG PHONE CALL Juan Pablo Gómez-Gozález 20 th April

5Lines Analysis Juan Pablo Gómez-González OUTLINE Summary of the Valencia PLS analysis with 5-line data Data sample selection based in optimum sensitivity Data-MC comparisons (quick review) Analysis techniques Sensitivities w/ & w/o systematics Candidate source list Conclusions 2

5Lines Analysis Juan Pablo Gómez-González OUTLINE Ingredients for the PLS analysis Declination distribution of real data events reconstructed with Bbfit strategy Detector performance: Neutrino angular resolution  inject signal events Neutrino effective area  get flux limits 3 Techniques to look for point sources Binned method Unbinned  EM algorithm (crosscheck with 1 free parameter EM)

5Lines Analysis Juan Pablo Gómez-González DECLINATION DISTRIBUTION 4 The proposed cut (see previous presentations) is   < 1.8 This sample contains 331 events from real data  data νμ bg  data νμ bg New MC production (option –C2) used to simulate atmospheric muons CORSIKA with Fluka parametrization

5Lines Analysis Juan Pablo Gómez-González QUALITY OF THE RECONSTRUCTION 5 elevation < -10   cumulative distribution Good agreement in the region selected New muon mc simulation (option -C2 in TriggerEfficiency)

5Lines Analysis Juan Pablo Gómez-González DETECTOR PERFORMANCE 6 Angular resolution As a function of the neutrino energy In function of the declination angle Weighted by a neutrino flux of E^-2 Offline reconstruction strategy: no optimal angular resolution but most robust dealing With background noise Between 3 and 5 degrees depending on the declination

5Lines Analysis Juan Pablo Gómez-González DETECTOR PERFORMANCE 7 Neutrino Effective area Effective area (averaged over the neutrino energy) weighted by a neutrino flux of E^-2 as a function of the declination Effective area as a function of the neutrino energy Used to compute flux limits

5Lines Analysis Juan Pablo Gómez-González FIXED SOURCE SEARCH 8 We look for clusters at a given direction in the sky As our search is centred at a specific region the probability of the background to mimic a source results reduced In absence of signal an upper limit to the flux 5.5e-8 cm^-2 s^-1 at dec = -60º can be set The average increase of the unbinned method over the binned oneis about 25%. Results from the fixed sigma method compatibles

5Lines Analysis Juan Pablo Gómez-González FIXED SOURCE SEARCH 9 Discovery Potentials (EM) Percentage of success of discovering a point-like source over the atmospheric neutrino background 5 events coming from a source at dec = -30º to have a 50% probability of a 3sigma discovery 9 events coming from a source at dec = -30º to have a 50% probability of a 5sigma discovery

5Lines Analysis Juan Pablo Gómez-González ALL SKY SEARCH 10 Discovery Power (EM) Almost 11 events coming from a source at dec = -30º to have a 50% probability of a 3sigma discovery No assumption about the position of the source is made Worst signal-bg discrimination Binned method Dicovey flux  0.4e-7 cm^-2 s^-1 (dec = -60º) Events needed for a dicovery (3sigmas, 50% SP) trasleted to fluc

5Lines Analysis Juan Pablo Gómez-González SYSTEMATICS COMPUTATION 11 Compute the impact on the limits when we are considering systematics effects Binned method Unbinned method (up) Efficiency  15% (dw) Angular resolution Efficiency (up left) Angular resolution (up right) Both effect s(dw) 1)25 % impact 2)10% “ “ 3)30 % ” “

5Lines Analysis Juan Pablo Gómez-González CANDIDATE SOURCE LIST 12 The list is kept but the Ice-Cube hotspot could be removed Presented in Conferences Documented: ANTARES-PHYS Sky map of sources selected in galactic coordinates together with the ANTARES visibility

5Lines Analysis Juan Pablo Gómez-González CONCLUSIONS 13 Complete analysis with 5-lines detector data presented (but All sky sensitivity curves near) Reconstruction quality parameter (BBfit strategy) show a good agreement in the region selected Final sample chosen (optimum sensitivity) contains 331 events Two different techniques (Binned method and EM-algorithm) used following to different approaches (Fixed source search and All sky search) List of candidate sources already documented Web page and an Internal note work almost done (review process)