Precession during merger 1: Strong polarization changes are observationally accessible features of strong-field gravity during binary black hole merger

The short gravitational wave signal from the merger of compact binaries encodes a surprising amount of information about the strong-field dynamics of merger into frequencies accessible to ground-based interferometers. In this paper we describe a previously-unknown "precession" of the peak emission direction with time, both before and after the merger, about the total angular momentum direction. We demonstrate the gravitational wave polarization encodes the orientation of this direction to the line of sight. We argue the effects of polarization can be estimated nonparametrically, directly from the gravitational wave signal as seen along one line of sight, as a slowly-varying feature on top of a rapidly-varying carrier. After merger, our results can be interpreted as a coherent excitation of quasinormal modes of different angular orders, a superposition which naturally "precesses" and modulates the line-of-sight amplitude. Recent analytic calculations have arrived at a similar geometric interpretation. We suspect the line-of-sight polarization content will be a convenient observable with which to define new high-precision tests of general relativity using gravitational waves. Additionally, as the nonlinear merger process seeds the initial coherent perturbation, we speculate the amplitude of this effect provides a new probe of the strong-field dynamics during merger. To demonstrate the ubiquity of the effects we describe, we summarize the post-merger evolution of 104 generic precessing binary mergers. Finally, we provide estimates for the detectable impacts of precession on the waveforms from high-mass sources. These expressions may identify new precessing binary parameters whose waveforms are dissimilar from the existing sample.Comment: 11 figures; v2 includes response to referee suggestion

Erodibility of hill peat

peer-reviewedThe project was funded by the European Union Structural Funds EAGGF distributed under the Department of Agriculture and Food Stimulus Fund.The energy necessary to entrain soil in water depends on the soil strength. Once entrained, the settling velocity of the eroded soil in water is of fundamental importance to the processes of sediment transport and deposition. In this paper, stream power theory and transport concepts coupled with the equation of continuity were used to derive a transport-limited peat concentration. The ratio of the log of the actual sediment concentration in surface run-off to the log of the transport-limited sediment concentration was the index of erosion used. The value of this index is a measure of the sensitivity of peat to erosion by sheet flow. Four peats were subjected to a range of overland flow rates under two slopes in a laboratory flume. The peats represented peat farmed in a sustainable manner (Leenane), overgrazed peat (Maam), peat undergoing erosion (Newport) and peat which had undergone weathering following exposure by a landslip (Croagh Patrick). Both in situ and surface damaged slabs were studied. The results indicate that shearing and remoulding of a wet peat surface (e.g., by animal treading) and weathering of exposed drained peat surfaces predispose peat to erosion. Defoliation by overgrazing is considered to be of secondary importance.Department of Agriculture, Food and the MarineEuropean Union Structural Funds EAGG

Prediction Markets: Alternative Mechanisms for Complex Environments with Few Traders

Double auction prediction markets have proven successful in large-scale applications such as elections and sporting events. Consequently, several large corporations have adopted these markets for smaller-scale internal applications where information may be complex and the number of traders is small. Using laboratory experiments, we test the performance of the double auction in complex environments with few traders and compare it to three alternative mechanisms. When information is complex we find that an iterated poll (or Delphi method) outperforms the double auction mechanism. We present five behavioral observations that may explain why the poll performs better in these settings

Impact of pig slurry amendments on phosphorus, suspended sediment and metal losses in laboratory runoff boxes under simulated rainfall

peer-reviewedLosses of phosphorus (P) when pig slurry applications to land are followed by a rainfall event or losses from soils with high P contents can contribute to eutrophication of receiving waters. The addition of amendments to pig slurry spread on high P Index soils may reduce P and suspended sediment (SS) losses. This hypothesis was tested at laboratory-scale using runoff boxes under simulated rainfall conditions. Intact grassed soil samples, 100 cm-long, 22.5 cm-wide and 5 cm-deep, were placed in runoff boxes and pig slurry or amended pig slurry was applied to the soil surface. The amendments examined were: (1) commercial grade liquid alum (8% Al2O3) applied at a rate of 0.88:1 [Al:total phosphorus (TP)] (2) commercial-grade liquid ferric chloride (38% FeCl3) applied at a rate of 0.89:1 [Fe:TP] and (3) commercial-grade liquid poly-aluminium chloride (PAC) (10% Al2O3) applied at a rate of 0.72:1 [Al:TP]. The grassed soil was then subjected to three rainfall events (10.3 ± 0.15 mm h−1) at time intervals of 48, 72, and 96 h following slurry application. Each sod received rainfall on 3 occasions. Results across three rainfall events showed that for the control treatment, the average flow weighted mean concentration (FWMC) of TP was 0.61 mg L−1, of which 31% was particulate phosphorus (PP), and the average FWMC of SS was 38.1 mg L−1. For the slurry treatment, there was an average FWMC of 2.2 mg TP L−1, 47% of which was PP, and the average FWMC of SS was 71.5 mg L−1. Ranked in order of effectiveness from best to worst, PAC reduced the average FWMC of TP to 0.64 mg L−1 (42% PP), FeCl3 reduced TP to 0.91 mg L−1 (52% PP) and alum reduced TP to 1.08 mg L−1 (56% PP). The amendments were in the same order when ranked for effectiveness at reducing SS: PAC (74%), FeCl3 (66%) and alum (39%). Total phosphorus levels in runoff plots receiving amended slurry remained above those from soil only, indicating that, although incidental losses could be mitigated by chemical amendment, chronic losses from the high P index soil in the current study could not be reduced.The first author gratefully acknowledges the award of the EMBARK scholarship from IRCSET to support this study

Quality management and e-commerce: the role of codes of conduct governing the use of technology

Discussion of the relationship between TQM and information and communications technology (ICT) normally focuses either on technological issues, or on the role of ICT in enabling the achievement of quality goals by means of business process re-engineering. Less attention has been paid to the effects that the increased utilisation of ICT is having on management style, and on the quality of relationships. This paper reports on research undertaken into the development, implementation and enforcement of codes of conduct designed to govern employees' use of ICT. A study of 125 London-based employers found that, although such codes had been introduced in nearly three-quarters of the organisations, the majority failed to address a key issue of concern to customers' privacy of personal data. Furthermore, the codes themselves were seen to have little influence on the behaviour of employees. The reasons for this are discussed within a TQM framework, and suggestions made as to how compliance might be improved in future