A Search for Hierarchical Triples using Kepler Eclipse Timing

We present the first results of a Kepler survey of 41 eclipsing binaries that we undertook to search for third star companions. Such tertiaries will periodically alter the eclipse timings through light travel time and dynamical effects. We discuss the prevalence of starspots and pulsation among these binaries and how these phenomena influence the eclipse times. There is no evidence of short period companions (P < 700 d) among this sample, but we do find evidence for long term timing variations in 14 targets (34%). We argue that this finding is consistent with the presence of tertiary companions among a significant fraction of the targets, especially if many have orbits measured in decades. This result supports the idea that the formation of close binaries involves the deposition of angular momentum into the orbital motion of a third star.Comment: AJ, in press, 104 pages, 2 figure sets plus 1 regular figur

A hierarchical search for gravitational waves from supermassive black hole binary mergers

We present a method to search for gravitational waves from coalescing supermassive binary black holes in LISA data. The search utilizes the $\mathcal{F}$-statistic to maximize over, and determine the values of, the extrinsic parameters of the binary system. The intrinsic parameters are searched over hierarchically using stochastically generated multi-dimensional template banks to recover the masses and sky locations of the binary. We present the results of this method applied to the mock LISA data Challenge 1B data set.Comment: 11 pages, 2 figures, for GWDAW-12 proceedings edition of CQ

「中国ビジネス最前線視察団」に参加して

1.はじめに　2. 旅程　3. テレビ番組　4. 上海および広州の水　5. 中国で活躍する日本企業　6. おわりに

The Pioneer Anomaly

Radio-metric Doppler tracking data received from the Pioneer 10 and 11 spacecraft from heliocentric distances of 20-70 AU has consistently indicated the presence of a small, anomalous, blue-shifted frequency drift uniformly changing with a rate of ~6 x 10^{-9} Hz/s. Ultimately, the drift was interpreted as a constant sunward deceleration of each particular spacecraft at the level of a_P = (8.74 +/- 1.33) x 10^{-10} m/s^2. This apparent violation of the Newton's gravitational inverse-square law has become known as the Pioneer anomaly; the nature of this anomaly remains unexplained. In this review, we summarize the current knowledge of the physical properties of the anomaly and the conditions that led to its detection and characterization. We review various mechanisms proposed to explain the anomaly and discuss the current state of efforts to determine its nature. A comprehensive new investigation of the anomalous behavior of the two Pioneers has begun recently. The new efforts rely on the much-extended set of radio-metric Doppler data for both spacecraft in conjunction with the newly available complete record of their telemetry files and a large archive of original project documentation. As the new study is yet to report its findings, this review provides the necessary background for the new results to appear in the near future. In particular, we provide a significant amount of information on the design, operations and behavior of the two Pioneers during their entire missions, including descriptions of various data formats and techniques used for their navigation and radio-science data analysis. As most of this information was recovered relatively recently, it was not used in the previous studies of the Pioneer anomaly, but it is critical for the new investigation.Comment: 165 pages, 40 figures, 16 tables; accepted for publication in Living Reviews in Relativit

Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler

We report the distribution of planets as a function of planet radius (R_p), orbital period (P), and stellar effective temperature (Teff) for P < 50 day orbits around GK stars. These results are based on the 1,235 planets (formally "planet candidates") from the Kepler mission that include a nearly complete set of detected planets as small as 2 Earth radii (Re). For each of the 156,000 target stars we assess the detectability of planets as a function of R_p and P. We also correct for the geometric probability of transit, R*/a. We consider first stars within the "solar subset" having Teff = 4100-6100 K, logg = 4.0-4.9, and Kepler magnitude Kp < 15 mag. We include only those stars having noise low enough to permit detection of planets down to 2 Re. We count planets in small domains of R_p and P and divide by the included target stars to calculate planet occurrence in each domain. Occurrence of planets varies by more than three orders of magnitude and increases substantially down to the smallest radius (2 Re) and out to the longest orbital period (50 days, ~0.25 AU) in our study. For P < 50 days, the radius distribution is given by a power law, df/dlogR= k R^\alpha. This rapid increase in planet occurrence with decreasing planet size agrees with core-accretion, but disagrees with population synthesis models. We fit occurrence as a function of P to a power law model with an exponential cutoff below a critical period P_0. For smaller planets, P_0 has larger values, suggesting that the "parking distance" for migrating planets moves outward with decreasing planet size. We also measured planet occurrence over Teff = 3600-7100 K, spanning M0 to F2 dwarfs. The occurrence of 2-4 Re planets in the Kepler field increases with decreasing Teff, making these small planets seven times more abundant around cool stars than the hottest stars in our sample. [abridged]Comment: Submitted to ApJ, 22 pages, 10 figure

Two images of Nantes as a ‘Green Model’ of Urban Planning and Governance: The ‘Collaborative City’ Versus the ‘Slow City’

This article examines how the city of Nantes, European Green Capital in 2013, came to promote plans for a new international airport at Notre-Dame-des-Landes. Deploying poststructuralist discourse theory, it analyses how the highly politicised struggle against the airport reveals the limits of the Nantes model of urban sustainability and collaboration, giving rise to a counter model, which we provisionally characterise as the ‘slow city’. While the struggle against the airport can be understood as a rural social movement, we show how its ideals and logics have been progressively displaced to Nantes itself, disclosing new images and possibilities of urban governance

Orientalising deafness: race and disability in imperial Britain

This article explores the conflations and connections that postcolonial and disability scholars have drawn between ‘race’, ‘colonialism’ and ‘disability’ from a historical perspective. By looking at the connections drawn between ‘race’ and ‘disability’ in the context of nineteenth-century imperial Britain, I hope to probe beyond them to examine the origins and implications of their interplay. I do so by focusing on ideas about deafness, an impairment radically reconfigured in the colonial period, and inflected with concerns about degeneration, belonging, heredity and difference. Disability, I argue, not only operated as an additional ‘category of difference’ alongside ‘race’ as a way of categorising and subjugating the various ‘others’ of Empire, but intersected with it. The ‘colonisation’ of disabled people in Britain and the ‘racial other’ by the British were not simply simultaneous processes or even analogous ones, but were part and parcel of the same cultural and discursive system. The colonising context of the nineteenth century, a period when British political, economic and cultural expansion over areas of South Asia, Australasia and Africa increased markedly, structured the way in which all forms of difference were recognised and expressed, including the difference of deafness. So too did the shifts in the raced and gendered thinking that accompanied it, as new forms of knowledge were developed to justify, explain and contest Britain's global position and new languages were developed through which to articulate otherness. Such developments reconfigured the meaning of disability. Disability was, in effect, ‘orientalised’. ‘Race’ I argue was formative in shaping what we have come to understand as ‘disability’ and vice versa; they were related fantasies of difference