Rapid Bayesian position reconstruction for gravitational-wave transients

Within the next few years, Advanced LIGO and Virgo should detect gravitational waves from binary neutron star and neutron star-black hole mergers. These sources are also predicted to power a broad array of electromagnetic transients. Because the electromagnetic signatures can be faint and fade rapidly, observing them hinges on rapidly inferring the sky location from the gravitational-wave observations. Markov chain Monte Carlo methods for gravitational-wave parameter estimation can take hours or more. We introduce BAYESTAR, a rapid, Bayesian, non-Markov chain Monte Carlo sky localization algorithm that takes just seconds to produce probability sky maps that are comparable in accuracy to the full analysis. Prompt localizations from BAYESTAR will make it possible to search electromagnetic counterparts of compact binary mergers.Comment: 23 pages, 12 figures, published in Phys. Rev.

IMPLICATIONS OF RAISING THE NONFAT SOLIDS STANDARDS FOR BEVERAGE MILK

An econometric model of the dairy industry was used to estimate the effects on farmers, consumers, and taxpayers of nationwide adoption of the California nonfat solids standards for fluid milk. It was estimated that adoption of the California standards would raise farm-level milk prices by 1 to 5 percent in the short run and by 1 to 2 percent in the long run. The average retail price of fluid milk would rise by 9 to 13 cents per gallon. Dairy program costs fall under most scenarios, but could rise if surpluses fall to levels that would trigger increases in the support price.Agricultural and Food Policy,

Marching Band Show Design Tips for Smaller Bands

This project takes an in depth look at the marching band scoring system in the attempt to aid small school bands. The adjudicator sheets of the competitive marching band circuit were evaluated to see what criteria judges are looking for in a performance. To attain the highest scoring rating, it seems that the performance needs to be original, captivating, and executed with high accuracy based on the research. The first two expectations, original and captivating, are objective to the individual and require custom elements, referred to as non-performance variables throughout the paper. This paper sought to find what judges look for and offer suggestions to aid small schools in the scoring process as compared to larger ensembles

The Local Ecological Effect of Long Tailed Jaegers Nesting in the Subarctic

While carrying out geomorphological field work in the Ruby Range, Yukon Territory ... during the summers of 1967 and 1968, an extension of the known breeding grounds of the long tailed jaeger (Stercorarius longicaudus) was observed. A pair of these birds nested on the same southeast-facing slope both years and their presence affected the local ecology in significant ways. For example, they maintained a constant vigil and promptly chased away any predator which came close to the slope. This provided an umbrella for other animals on the slope such as ground squirrels, pika, marmot, and ptarmigan. As a result the population of these animals was higher and their behaviour was more uninhibited than in surrounding areas. This became even more noticeable, by contrast, upon returning to the field in the summer of 1972 and finding the jaegers missing. The feather remains of one adult jaeger were discovered and the atmosphere on the slope was very different. ...Although the Ruby Range is approximately 900 km south of the previously documented nesting area of the long tailed jaeger, several jaegers were sighted here. My research was concerned with solifluction lobe development in the Ruby Range and detailed work was carried out on four adjacent slopes facing southeast, southwest, east, and north. ... The jaegers' nest was located in approximately the same place both years, on a lobe tread in a small basin between two mossy hummocks. ... Occasionally we would hear the jaegers begin their high shrill calls and look in the direction they were flying to see an eagle .... The same treatment was allotted other predators such as wolf, fox, bear, and wolverine. ... The virtual elimination of predators from the slope during the summer was somewhat counterbalanced by the jaegers themselves, however, since they harvested many small rodents on the slope, i.e., shrews, lemmings, voles, and mice of various kinds. But for the larger burrowing mammals, such as ground squirrels, pika, marmot, as well as the ptarmigan, it provided a rather trouble-free existence. On a comparative basis the population of burrowing animals was vastly greater on the southeast-facing slope than the other exposures, and although the major explanation for this may be because of the more favourable environment on the south-east, it is nevertheless felt that the jaegers' presence contributed significantly to the relatively high population. ... there was a clear and observable difference in the ecology of the slope because of the jaegers' presence. Such ecological relationships are replete in nature and we have a great deal to learn about and from them

The Collapse of Solifluction Lobes as a Factor in Vegetating Blockfields

In the Ruby Mt area of southwestern Yukon, tongues and islands of vegetation occur in certain blockfields, which through normal processes develop soil and vegetation only very slowly, due to a lack of near-surface water and great diurnal temperature extremes during summer. The collapse occurs when the lobes move from the meadow onto the steeper slope of the blockfield where composition of vegetation changes and where there is a deeper active layer. Once collapsed, they flow downslope transporting clumps of vegetation which may establish themselves along the mud-flow channel or levee. Thus certain arctic and alpine slopes are vegetated more quickly than would otherwise be possible.L'effondrement de lobes de solifluxion, facteur de colonisation des champs de blocs par la végétation. Selon les processus normaux, le développement du sol et de la végétation dans les champs de blocs est très lent. C'est pourquoi, dans les monts Ruby, dans le sud-ouest du territoire du Yukon, on est surpris de trouver des langues et des îlots de végétation au milieu de certains champs de blocs. On propose comme mécanisme responsable de ce phénomène l'effondrement des lobes de solifluxion des pentes voisines. En passant de la pente douce de l'alpe à celle, plus forte, des champs de blocs, les lobes ne peuvent plus se maintenir à cause de cette pente plus prononcée, du changement de composition de la végétation et de l'épaisseur plus grande du mollisol. En s'effondrant, les lobes fluent le long de la pente, entraînant des masses de végétation qui s'établissent quelque part le long du chenal de coulée ou sur ses levées. De cette façon, de petits avant-postes de végétation se créent et accélèrent ainsi le processus qui, autrement, serait interminablement plus long

Is A New Type of Checking Account Around the Corner?

Dr. Price is Professor of Finance and Chairman, Department of Finance and Law in the School of Business, Georgia Southern College

Conservative, gravitational self-force for a particle in circular orbit around a Schwarzschild black hole in a Radiation Gauge

This is the second of two companion papers on computing the self-force in a radiation gauge; more precisely, the method uses a radiation gauge for the radiative part of the metric perturbation, together with an arbitrarily chosen gauge for the parts of the perturbation associated with changes in black-hole mass and spin and with a shift in the center of mass. We compute the conservative part of the self-force for a particle in circular orbit around a Schwarzschild black hole. The gauge vector relating our radiation gauge to a Lorenz gauge is helically symmetric, implying that the quantity h_{\alpha\beta} u^\alpha u^\beta (= h_{uu}) must have the same value for our radiation gauge as for a Lorenz gauge; and we confirm this numerically to one part in 10^{13}. As outlined in the first paper, the perturbed metric is constructed from a Hertz potential that is in term obtained algebraically from the the retarded perturbed spin-2 Weyl scalar, \psi_0 . We use a mode-sum renormalization and find the renormalization coefficients by matching a series in L = \ell + 1/2 to the large-L behavior of the expression for the self-force in terms of the retarded field h_{\alpha\beta}^{ret}; we similarly find the leading renormalization coefficients of h_{uu} and the related change in the angular velocity of the particle due to its self-force. We show numerically that the singular part of the self-force has the form f_{\alpha} \propto < \nabla_\alpha \rho^{-1}>, the part of \nabla_\alpha \rho^{-1} that is axisymmetric about a radial line through the particle. This differs only by a constant from its form for a Lorenz gauge. It is because we do not use a radiation gauge to describe the change in black-hole mass that the singular part of the self-force has no singularity along a radial line through the particle and, at least in this example, is spherically symmetric to subleading order in \rho.Comment: 21 pages, 2 figure

The CHA's Plan for Transformation: How Have Residents Fared?

Summarizes findings from studies on how relocation from distressed public housing changed former residents' quality of life, including living conditions, safety, poverty, employment, health, well-being of children, and satisfaction. Outlines implications

Tiling strategies for optical follow-up of gravitational wave triggers by wide field of view telescopes

Binary neutron stars are among the most promising candidates for joint gravitational-wave and electromagnetic astronomy. The goal of this work is to investigate the strategy of using gravitational wave sky-localizations for binary neutron star systems, to search for electromagnetic counterparts using wide field of view optical telescopes. We examine various strategies of scanning the gravitational wave sky-localizations on the mock 2015-16 gravitational-wave events. We propose an optimal tiling-strategy that would ensure the most economical coverage of the gravitational wave sky-localization, while keeping in mind the realistic constrains of transient optical astronomy. Our analysis reveals that the proposed tiling strategy improves the sky-localization coverage over naive contour-covering method. The improvement is more significant for observations conducted using larger field of view telescopes, or for observations conducted over smaller confidence interval of gravitational wave sky-localization probability distribution. Next, we investigate the performance of the tiling strategy for telescope arrays and compare their performance against monolithic giant field of view telescopes. We observed that distributing the field of view of the telescopes into arrays of multiple telescopes significantly improves the coverage efficiency by as much as 50% over a single large FOV telescope in 2016 localizations while scanning around 100 sq. degrees. Finally, we studied the ability of optical counterpart detection by various types of telescopes. In Our analysis for a range of wide field-of-view telescopes we found improvement in detection upon sacrificing coverage of localization in order to achieve greater observation depth for very large field-of-view - small aperture telescopes, especially if the intrinsic brightness of the optical counterparts are weak.Comment: Accepted for publication in A&A. 10 pages, 10 figure

Assessing Online Viewing Practices Among College Students

This article focuses on media literacy education for college students. First, we conducted psychometric analyses to verify the properties of the Critical Evaluation and Analysis of Media (CEAM) scale. CEAM measures college students’ self-reported practices for critically evaluating and analyzing the credibility, audience, and technical design elements of online media, such as news, advertisement, and entertainment media. Using CEAM, our second goal was to identify trends in critical viewing practices among first-year students enrolled in college. Results of confirmatory factor analysis (CFA) and item response theory (IRT) supported a three-factor structure for the CEAM scale. Composite score reliability for all items comprising the total scale displayed strong evidence for the internal consistency of the scale with a Coefficient Alpha (α) of .91. Score reliability estimates for each subscale follow: (a) Questioning Credibility (α = .80), (b) Recognizing Audience (α = .78), and (c) Recognizing Design (α = .81). Findings from the study indicate that while first-year college students generally perceive they have adequate practices in recognizing audience in media messages and questioning the credibility of news, there is room for improvement in questioning the credibility of advertisements, suggesting that college instructors should focus more on advertising literacy