Distinguishing transient signals and instrumental disturbances in semi-coherent searches for continuous gravitational waves with line-robust statistics

11th Edoardo Amaldi Conference on Gravitational Waves

Keitel, David^1

Albert-Einstein-Institut, Callinstr. 38, Hannover

30167, Germany^1

关键词: Bayesian approaches;    Bayesian model selection;    Computational costs;    Continuous-wave signals;    Detection statistic;    Interferometric detectors;    Quasi-monochromatic;    Transient disturbances;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/716/1/012003/pdf
DOI  :  10.1088/1742-6596/716/1/012003

来源: IOP

【 摘 要 】

Non-axisymmetries in rotating neutron stars emit quasi-monochromatic gravitational waves. These long-duration 'continuous wave' signals are among the main search targets of ground-based interferometric detectors. However, standard detection methods are susceptible to false alarms from instrumental artefacts that resemble a continuous-wave signal. Past work [Keitel, Prix, Papa, Leaci and Siddiqi 2014, Phys. Rev. D 89 064023] showed that a Bayesian approach, based on an explicit model of persistent single-detector disturbances, improves robustness against such artefacts. Since many strong outliers in semi-coherent searches of LIGO data are caused by transient disturbances that last only a few hours or days, I describe in a recent paper [Keitel D 2015, LIGO-P1500159] how to extend this approach to cover transient disturbances, and demonstrate increased sensitivity in realistic simulated data. Additionally, neutron stars could emit transient signals which, for a limited time, also follow the continuous-wave signal model. As a pragmatic alternative to specialized transient searches, I demonstrate how to make standard semi-coherent continuous-wave searches more sensitive to transient signals. Focusing on the time-scale of a single segment in the semi-coherent search, Bayesian model selection yields a simple detection statistic without a significant increase in computational cost. This proceedings contribution gives a brief overview of both works.