1 / 17

Upper limit map of a Gravitational Wave Background

Upper limit map of a Gravitational Wave Background. For the stochastic analysis group Stefan Ballmer California Institute of Technology. Outline. Reminder: The S4 Radiometer analysis Additional checks since August LSC meeting (Asked for by review committee). Detection Strategy, point source.

cwest
Télécharger la présentation

Upper limit map of a Gravitational Wave Background

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. Upper limit map of aGravitational Wave Background For the stochastic analysis group Stefan Ballmer California Institute of Technology Stefan Ballmer, Caltech

  2. Outline • Reminder: The S4 Radiometer analysis • Additional checks since August LSC meeting(Asked for by review committee) Stefan Ballmer, Caltech

  3. Detection Strategy, point source Point Spread Function • Cross-correlation estimator • Theoretical variance • Optimal Filter Strain Power: Choose N such that: Stefan Ballmer, Caltech

  4. S4 Upper Limit map , H(f)=const Stefan Ballmer, Caltech

  5. S4 Upper Limit map , H(f)~f-3 Stefan Ballmer, Caltech

  6. Frequency dependentStrain Upper Limit Sco-X1 Artist’s impression: NASA Strain (RMS) Stefan Ballmer, Caltech

  7. Software InjectionPoint Sources at 1e-47 (SNR~10) BTW: Isotropic search returns only a 1.2 sigma result for this! Stefan Ballmer, Caltech

  8. Software InjectionPoint Sources # ra dec Inj. Point_Estimate ratio Sigma SNR ----------------------------------------------------------------------------- 1 6 45 2e-48 1.474e-48 0.7368 9.456e-49 1.559 2 9 -60 2e-48 2.831e-48 1.415 1.102e-48 2.569 3 12 60 2e-48 1.839e-48 0.9193 9.913e-49 1.855 4 15 -75 2e-48 3.009e-48 1.505 1.171e-48 2.569 5 18 0 2e-48 3.068e-48 1.534 1.267e-48 2.422 1 6 45 1e-47 9.602e-48 0.9602 9.5e-49 10.11 2 9 -60 1e-47 1.032e-47 1.032 1.105e-48 9.34 3 12 60 1e-47 1.014e-47 1.014 1.005e-48 10.09 4 15 -75 1e-47 1.102e-47 1.102 1.175e-48 9.38 5 18 0 1e-47 1.065e-47 1.065 1.276e-48 8.349 Stefan Ballmer, Caltech

  9. Effect of timing transient Stefan Ballmer, Caltech

  10. Effect of timing transient Stefan Ballmer, Caltech

  11. Effect of timing transientDifference But is there a residual effect? Stefan Ballmer, Caltech

  12. Effect of timing transientDifference between H1 and L1 TT There is a small systematic associated with this… Stefan Ballmer, Caltech

  13. Conservative estimateof systematic error • Use maximumdifference betweenL1 and H1, x 1/sqrt(2)as maximum errorestimate • Use no-subtraction minus H1-subtraction difference as position dependence map • Add systematic to statistical error in quadrature Stefan Ballmer, Caltech

  14. Change in upper limit mapBefore Stefan Ballmer, Caltech

  15. Change in upper limit mapAfter Stefan Ballmer, Caltech

  16. Summary • Most questions/remarks from review committee addressed • Will be presented at Texas Symposium, Melbourne • Some minor corrections needed for Paper, will becirculated to LSC shortly. Stefan Ballmer, Caltech

  17. The End Stefan Ballmer, Caltech

More Related