1 / 18

Recent Advances in Neutrino Detection: Analysis Strategies and Results Overview from AMANDA-II

This overview presents analysis strategies and recent results from AMANDA-II, a neutrino detection experiment. Topics covered include point-source searches, stacking of AGN sources, diffuse energy spectrum analysis, and more innovative strategies like transient searches and searches for dark matter candidates. AMANDA-II comprises 677 PMTs on 19 strings detecting Cherenkov light at the South Pole. Key results include limits on single point sources and stacking of AGN sources. No significant signals above the atmospheric flux have been detected so far, but these analyses provide valuable insights and constraints on current models. Future efforts will continue with IceCube.

helencohen
Download Presentation

Recent Advances in Neutrino Detection: Analysis Strategies and Results Overview from AMANDA-II

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. Analysis strategies and recent results from AMANDA-II

  2. Overview • Introduction: • Neutrino detection • AMANDA-II • Analysis strategies results: • Point-source • Stacking of point-source (AGN) • Isotropic / diffuse analysis • Diffuse energy spectrum

  3. Astroparticle physics

  4. 677 PMTs on 19 strings Cherenkov light South Pole Dome road to work AMANDA Summer camp 1500 m Amundsen-Scott South Pole Station 2000 m [not to scale] AMANDA/IceCube

  5. Stacking strategy – sum signal of point sources of same source class Search for a diffuse signal: use complete northern hemisphere Analysis strategies Point source searches – significance map ?clustering of neutrinos identified photon sources AMANDA/IceCube field of view: northern hemisphere

  6. Other strategies • Cascade analyses • Transient searches: • Flares of permanent objects • Gamma Ray Bursts  stacking approach, temporal clustering • SGR 1860-20 • Dark matter searches • WIMPs • Magnetic Monopoles • Atmospheric muons, charm contribution great but too short time!

  7. Search for single point sources Event map 4282 events in 5 years (2000-2004) –effective time: 1001 days 90% confidence levelflux upper limits for the northern hemisphere in 0.5 deg bins (15% systematic error included) Achterberg et al. 2007,astro-ph/0611063

  8. Search for single point sources Limit map No significant signal 90% confidence levelflux upper limits for the northern hemisphere in 0.5 deg bins (15% systematic error included) Achterberg et al. 2007,astro-ph/0611063

  9. Stacking of AGN • GeV blazars (EGRET) – GeV • Unidentified EGRET sources – unidGeV • Infrared sources – IR • HAEO-A-detected keV sources – keV(H) • ROSAT-detected keV sources – keV(R) • TeV blazars - TeV • Compact Steep Spectrum and Giga-Hertz peaked sources – CSS/GpS • FR-I galaxies including M87 – FR-I(M) • FR-I galaxies without M87 – FR-I • FR-II galaxies – FR-II • Radio-weak quasars – QSO Achterberg et al. 2007,astro-ph/0611063

  10. Stacking of AGN Achterberg et al. 2007,astro-ph/0611063

  11. Isotropic / diffuse analysis • Atmospheric neutrino flux follows Eν-3.7 • Search for extra-galactic contribution • AGN (1) (Becker/Biermann/ Rhode) • AGN (3 and 4) (Mannheim/Protheroe/ Rachen) • GRBs (2) (Waxman/Bahcall)

  12. AMANDA 2000-03 W-B IceCube 1 yr Isotropic / diffuse analysis Achterberg et al., astro-ph/0705.1315

  13. Diffuse energy spectrum • General case: • measured distr. → unfolding → true distr. • Using RUN for unfolding: • measured distr. A (E) • measured distr. B (E) → RUN → energy distribution • measured distr. C (E) • More than three measured distributions (E): • combine N-2 observables to a new variable • using a neural network for combining

  14. Diffuse energy spectrum variable 1 variable 2 variable 3 variable 4 variable 5 variable 6 Neural Net RUN variable 7 variable 8

  15. Diffuse energy spectrum comparison: result 2000 with 2000-2003 preliminary preliminary

  16. Fit on atm. prediction (2000-2003) preliminary preliminary • Fit on the atmos. prediction (Volkova) • (atmos.+ extrat.)  flux – (fit value)  flux

  17. Limits preliminary [1] Achterberg et al., astro-ph/0705.1315

  18. Summary • Data from 2000-2004 taken with AMANDA-II are analyzed • Different search strategies: • Steady point sources (single sources & stacking) • Diffuse search, spectrum up to 100 TeV • …and more… • Analyses show so far no signal above atmospheric flux • Constraints on current models possible • Future: IceCube

More Related