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arXiv · 1407.8333

Method for all-sky searches of continuous gravitational wave signals using the frequency-Hough transform

Pia Astone·Alberto Colla·Sabrina D'Antonio·Sergio Frasca·Cristiano Palomba
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Abstract

In this paper we present a hierarchical data analysis pipeline for all-sky searches of continuous gravitational wave signals, like those emitted by spinning neutron stars asymmetric with respect to the rotation axis, with unknown position, rotational frequency and spin-down. The core of the pipeline is an incoherent step based on a particularly efficient implementation of the Hough transform, that we call frequency-Hough, that maps the data time-frequency plane to the source frequency/spin-down plane for each fixed direction in the sky. Theoretical ROCs and sensitivity curves are computed and the dependency on various thresholds is discussed. A comparison of the sensitivity loss with respect to an "optimal" method is also presented. Several other novelties, with respect to other wide-parameter analysis pipelines, are also outlined. They concern, in particular, the construction of the grid in the parameter space, with over-resolution in frequency and parameter refinement, candidate selection and various data cleaning steps which are introduced to improve search sensitivity and rejection of false candidates.

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Pia Astone, Alberto Colla, Sabrina D'Antonio, Sergio Frasca, Cristiano Palomba. 2014-07-31. Method for all-sky searches of continuous gravitational wave signals using the frequency-Hough transform. https://doi.org/10.1103/physrevd.90.042002

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