1 / 7

“Instrumental” Interpretation of the Burst Search

“Instrumental” Interpretation of the Burst Search. Peter Saulson Syracuse University LIGO-G020081-00-Z. Outline. 1. Why an “instrumental” interpretation? 2. Filters for the instrumental interpretation 3. Pipeline of the instrumental interpretation

kenadia
Download Presentation

“Instrumental” Interpretation of the Burst Search

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. “Instrumental” Interpretation of the Burst Search Peter Saulson Syracuse University LIGO-G020081-00-Z Burst Group Instrumental Interpretation Overview

  2. Outline 1. Why an “instrumental” interpretation? 2. Filters for the instrumental interpretation 3. Pipeline of the instrumental interpretation 4. Constructing an instrumental upper limit 5. Open questions Burst Group Instrumental Interpretation Overview

  3. Why an instrumental interpretation? The Burst Group is charged with looking for signals whose waveforms aren’t predicted. Our tools are designed with this in mind. We can interpret our results in terms of astronomical models. But given our assumption of ignorance, we need to be sure to interpret our search with a minimum of assumptions about the signals. Instrumental interpretation stays closest to the measurement. We’ll say there were no gravity waves stronger than X at a rate of Y, in each of a large set of tiles in the time-frequency plane. Burst Group Instrumental Interpretation Overview

  4. Filters for the instrumental interpretation By assumption, we aren’t doing matched filtering. We want to look with eyes wide open. At as wide a set of durations and frequency bands as we can. Any DSO could be useful for the instrumental interpretation. Simplest to describe in terms of the excess power statistic, with its explicit coverage of t-f plane. Burst Group Instrumental Interpretation Overview

  5. Pipeline for the instrumental interpretation For each t-f tile: 1. Generate single-ifo triggers, with low threshold. 2. Find coincident events, and make histogram. 3. Construct ensemble of false-coincidence histograms, to determine probability distribution for each bin of coincidence histogram. 4. Test actual coincidence histogram for consistency with chance. 5. Quantify any excess above chance rate. For set of t-f tiles: Include trials factor in discussion of significance. Burst Group Instrumental Interpretation Overview

  6. Constructing an instrumental upper limit Calibration checked by injection of simulated signals. But upper limit is quoted in terms of hrms or h(f) in a band, not in terms of particular signals. A rate vs. strength curve defines the upper limit for each tile. Burst Group Instrumental Interpretation Overview

  7. Open questions • How many t-f tiles? • Coincidence definition (e.g. req’t on strength match?) • Resolution of individual events into “best” tile? • Look only for events above threshold where we expect none, or can we set a more stringent upper limit? • Computational burden of many tiles, many trials for false coincidence histograms? Burst Group Instrumental Interpretation Overview

More Related