arXiv subjects

P. B. Covas

Publications and source records attributed to P. B. Covas.

21 records · Page 2Linked to original sources

arXiv2019

BinarySkyHough: a new method to search for continuous gravitational waves from unknown neutron stars in binary systems

Non-axysymmetric, fast-spinning unknown neutron stars in binary systems may emit continuous gravitational waves (nearly-monochromatic long-duration signals) which can be detected by ground-based detectors like LIGO and Virgo. In this paper we present a new pipeline, called $\textit{BinarySkyHough}$, that can carry out all-sky searches for neutron stars in binary systems by exploiting the usage of graphics processing units. We give a detailed explanation of this new pipeline, and we present simulations which allow us to estimate the sensitivity of the new pipeline, which is approximately twice as sensitive as the best active pipeline with a comparable computational cost.

astro-ph.IM↗

arXiv2018

Improving astrophysical parameter estimation via offline noise subtraction for Advanced LIGO

The Advanced LIGO detectors have recently completed their second observation run successfully. The run lasted for approximately 10 months and lead to multiple new discoveries. The sensitivity to gravitational waves was partially limited by correlated noise. Here, we utilize auxiliary sensors that witness these correlated noise sources, and use them for noise subtraction in the time domain data. This noise and line removal is particularly significant for the LIGO Hanford Observatory, where the improvement in sensitivity is greater than 20%. Consequently, we were also able to improve the astrophysical estimation for the location, masses, spins and orbital parameters of the gravitational wave progenitors.

astro-ph.IM↗

arXiv2018

Identification and mitigation of narrow spectral artifacts that degrade searches for persistent gravitational waves in the first two observing runs of Advanced LIGO

Searches are under way in Advanced LIGO and Virgo data for persistent gravitational waves from continuous sources, e.g. rapidly rotating galactic neutron stars, and stochastic sources, e.g. relic gravitational waves from the Big Bang or superposition of distant astrophysical events such as mergers of black holes or neutron stars. These searches can be degraded by the presence of narrow spectral artifacts (lines) due to instrumental or environmental disturbances. We describe a variety of methods used for finding, identifying and mitigating these artifacts, illustrated with particular examples. Results are provided in the form of lists of line artifacts that can safely be treated as non-astrophysical. Such lists are used to improve the efficiencies and sensitivities of continuous and stochastic gravitational wave searches by allowing vetoes of false outliers and permitting data cleaning.

astro-ph.IM↗