A more effective coordinate system for parameter estimation of precessing compact binaries from gravitational waves

Ground-based gravitational wave detectors are sensitive to a narrow range of frequencies, effectively taking a snapshot of merging compact-object binary dynamics just before merger. We demonstrate that by adopting analysis parameters that naturally characterize this 'picture', the physical parameters of the system can be extracted more efficiently from the gravitational wave data, and interpreted more easily. We assess the performance of MCMC parameter estimation in this physically intuitive coordinate system, defined by (a) a frame anchored on the binary's spins and orbital angular momentum and (b) a time at which the detectors are most sensitive to the binary's gravitational wave emission. Using anticipated noise curves for the advanced-generation LIGO and Virgo gravitational wave detectors, we find that this careful choice of reference frame and reference time significantly improves parameter estimation efficiency for BNS, NS-BH, and BBH signals.Comment: 11 pages, 5 figures, submitted to Phys. Rev.

Searching for binary coalescences with inspiral templates: Detection and parameter estimation

There has been remarkable progress in numerical relativity recently. This has led to the generation of gravitational waveform signals covering what has been traditionally termed the three phases of the coalescence of a compact binary - the inspiral, merger and ringdown. In this paper, we examine the usefulness of inspiral only templates for both detection and parameter estimation of the full coalescence waveforms generated by numerical relativity simulations. To this end, we deploy as search templates waveforms based on the effective one-body waveforms terminated at the light-ring as well as standard post-Newtonian waveforms. We find that both of these are good for detection of signals. Parameter estimation is good at low masses, but degrades as the mass of the binary system increases.Comment: 14 pages, submitted to proceedings of the NRDA08 meeting, Syracuse, Aug. 11-14, 200

Basic Parameter Estimation of Binary Neutron Star Systems by the Advanced LIGO/Virgo Network

Within the next five years, it is expected that the Advanced LIGO/Virgo network will have reached a sensitivity sufficient to enable the routine detection of gravitational waves. Beyond the initial detection, the scientific promise of these instruments relies on the effectiveness of our physical parameter estimation capabilities. The majority of this effort has been towards the detection and characterization of gravitational waves from compact binary coalescence, e.g. the coalescence of binary neutron stars. While several previous studies have investigated the accuracy of parameter estimation with advanced detectors, the majority have relied on approximation techniques such as the Fisher Matrix. Here we report the statistical uncertainties that will be achievable for optimal detection candidates (SNR = 20) using the full parameter estimation machinery developed by the LIGO/Virgo Collaboration via Markov-Chain Monte Carlo methods. We find the recovery of the individual masses to be fractionally within 9% (15%) at the 68% (95%) credible intervals for equal-mass systems, and within 1.9% (3.7%) for unequal-mass systems. We also find that the Advanced LIGO/Virgo network will constrain the locations of binary neutron star mergers to a median uncertainty of 5.1 deg^2 (13.5 deg^2) on the sky. This region is improved to 2.3 deg^2 (6 deg^2) with the addition of the proposed LIGO India detector to the network. We also report the average uncertainties on the luminosity distances and orbital inclinations of ideal detection candidates that can be achieved by different network configurations.Comment: Second version: 15 pages, 9 figures, accepted in Ap

The Miskito Settlement Landscape of Eastern Honduras, With Emphasis on the Moravian Contribution.

This dissertation documents the influence of Moravian missionary activities on the Miskito settlement landscape in eastern Honduras---particularly in the areas of settlement morphology, housing, agriculture, and cemeteries. Upon their arrival to the Mosquito Coast in 1849, the missionaries employed a three pronged approach consisting of proselyting, medical treatment, and education to convert the majority of the indigenous population. The missionaries\u27 resulting influence was a significant component and major cultural force in the development of a distinctive Protestant region within Catholic Central America. Moravian contributions to the settlement landscape in sixty-four Miskito villages of eastern Honduras were documented through field observations of material culture, interviews, photographs, and document research in the Moravian Church archives. This information was used to map a hierarchy of Moravian centers illustrating spatially varying degrees of Moravian influence on the Miskito settlement landscape. Principal findings included: (1) Missionaries\u27 modified Miskito settlement morphology by implementing a distinctive settlement type based on the Hurrnhut model whereby church buildings were located on a central square that was bisected by the village road; (2) Moravian church architecture in Honduras passed through three stages beginning with local forms and materials, continuing with European forms and both local and manufactured materials, and concluding with only imported, manufactured materials; (3) Moravian alterations to Miskito housing consisted of changes to form and materials including such the installation of outside walls and inside partitions, frame construction raised above the ground on posts, and the addition of an external kitchen and gallery; (4) Moravian influence on Miskito agriculture included the introduction of new seed crops, increased fruit tree cultivation, and the expansion of traditional dooryard gardens; (5) Missionaries modified Miskito burial practices by discouraging both the isingni ceremony and property destruction, and by instituting the Moravian Easter Dawn Service. Through the analysis of cultural landscapes this dissertation builds a greater understanding of (1) the role of religion in creating ethnic landscapes; (2) the historical and cultural processes involved in the development of a Protestant cultural region within Catholic Central America; and (3) how cultural landscapes may be used by indigenous, peoples to document claims to ancestral lands

Comparing the impact of authentic leadership on Italian and UK police officers’ discretionary power, well-being and commitment

© 2020, Emerald Publishing Limited. Purpose: This paper compares the impact of leadership behaviours on the discretionary power, and well-being, and affective commitment of police officers from Italy and the United Kingdom (UK). In contrast to Italy, UK is an example of a core-New Public Management (NPM) country that has implemented reforms, in turn, changing the management and administration of public organizations. Consequently, it is expected that there will be significant differences in the behaviour of police officers. In particular, the paper examines the antecedents and outcomes of police officers\u27 well-being. Design/methodology/approach: The study involves collecting and analysing survey data using Structural Equation Modelling from 220 Italian and 238 UK police officers. Findings: There was a significant path from Leadership to Discretionary Power to Employee Well-being to Affective Commitment – at least for the Italian sample. The UK sample does not have a significant link between leadership and discretionary power. Discretionary power was similarly low for both groups as was affective commitment. Authentic leadership and discretionary power explained approximately a third of their well-being, particularly discretionary power. Together, directly and indirectly (mediated by well-being), they explained at least a third of police officers\u27 commitment to their organization. Well-being appears to be the key to ensuring effective police officers. Research limitations/implications: The limitation of this paper includes the use of cross-sectional data (Podsakoff et al., 2003). However, a common latent factor (CLF) was included, and several items that were explained by common method variance were controlled, as per George and Pandey\u27s recommendations (2017). Additionally, a Harmon\u27s single factor test was applied to the data. Practical implications: The UK police officers have significantly lower commitment compared with the Italian police officers (non-commitment), and both Italian and UK police officers have less discretionary power and well-being compared with police from the United States of America (USA) police officers and other street-level bureaucrats (SLBs). The findings suggest that the present police leadership behaviours erode rather than supports police officers\u27 discretionary power and well-being, leading to a low organizational commitment. Leadership training will better prepare managers to ensure the well-being of police officers working under conditions of work intensification. Originality/value: The UK police officers have significantly lower commitment compared with the Italian police officers (non-commitment), and both Italian and UK police officers have less discretionary power and well-being compared with US police officers and other SLBs. The findings show that the police leadership erodes rather than supports police officers\u27 discretionary power and well-being, leading to low organizational commitment. Leadership models that enhance employee well-being rather than efficiency targets must be a priority if police are to be prepared to cope effectively with emergencies and pandemics

Potential Environmental Effects of Deepwater Floating Offshore Wind Energy Facilities

Over the last few decades, the offshore wind energy industry has expanded its scope from turbines mounted on foundations driven into the seafloor and standing in less than 60 m of water, to floating turbines moored in 120 m of water, to prospecting the development of floating turbines moored in ~1,000 m of water. Since there are few prototype turbines and mooring systems of these deepwater, floating offshore wind energy facilities (OWFs) currently deployed, their effects on the marine environment are speculative. Using the available scientific literature concerning appropriate analogs, including fixed-bottom OWFs, land-based wind energy facilities, wave and tidal energy devices, and oil and gas platforms, we conducted a qualitative systematic review to estimate the potential environmental effects of deepwater, floating OWFs during operation, as well as potential mitigation measures to address some of the effects. We evaluated six categories of potential effects: changes to atmospheric and oceanic dynamics due to energy removal and modifications, electromagnetic field effects on marine species from power cables, habitat alterations to benthic and pelagic fish and invertebrate communities, underwater noise effects on marine species, structural impediments to wildlife, and changes to water quality. Our synthesis of 89 articles selected for the review suggests that many of these potential effects could be mitigated to pose a low risk to the marine environment if developers adopt appropriate mitigation strategies and best-practice protocols. This review takes the necessary first steps in summarizing the available information on the potential environmental effects of deepwater, floating OWFs and can serve as a reference document for marine scientists and engineers, the energy industry, permitting agencies and regulators of the energy industry, project developers, and concerned stakeholders such as coastal residents, conservationists, and fisheries