28 research outputs found

    Progress in the Design of the Atacama Large Aperture Submillimeter Telescope

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    The Atacama Large Aperture Submillimeter Telescope (AtLAST) aims to be the premier next generation large diameter (50 meter) single dish observatory capable of observations across the millimeter/submillimeter spectrum, from 30~GHz to 1~THz. AtLAST will be sited in Chile at approximately 5100 meters above sea level, high in the Atacama Desert near Llano de Chajnantor. The novel rocking-chair telescope design allows for a unprecedentedly wide field of view (FoV) of 1-2∘^\circ diameter, a large receiver cabin housing six major instruments, and high structural stability during fast scanning operations (up to ∌3∘\sim 3^\circ per second in azimuth). Here we describe the current status of, and expected outcomes for, the antenna design study, which will be completed in 2024.Comment: Accepted for the URSI GASS 2023, Sapporo, Japan, 19-26 August 2023. 4 pages, 3 figure

    The Utility of Video Diaries for Organizational Research

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    This article assesses the utility of video diaries as a method for organization studies. While it is frequently suggested that video-based research methodologies have the capacity to capture new data about the minutiae of complex organizational affairs, as well as offering new forms of dissemination to both academic and professional audiences, little is known about the specific benefits and drawbacks of video diaries. We compare video diaries with two established and “adjacent” methods: traditional diary studies (written or audio) and other video methods. We evaluate each in relation to three key research areas: bodily expressions, identity, and practice studies. Our assessment of video diaries suggests that the approach is best used as a complement to other forms of research and is particularly suited to capturing plurivocal, asynchronous accounts of organizational phenomena. We use illustrations from an empirical research project to exemplify our claims before concluding with five points of advice for researchers wishing to employ this method

    Women In the weighing room: gender discrimination on the thoroughbred racetrack

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    Women jockeys are a small minority on the thoroughbred racetrack and securesignificantly fewer racing mounts than their male counterparts. This suggests female jockeys are facing discriminatory barriers, in one of the only major professional sportswhere men and women compete against each other on equal terms. This exploratorystudy considers discriminatory barriers that exist and the effects they have on women’scomparative profile and participation in the flat racing industry. Six participants wererecruited for the study from different areas within the industry, and with at least threeyears experience. Information was derived from semi structured individual interviews. The data was analysed using discourse analysis techniques. Five main themes wereevident: a culture of sexism, including the sense that women are more nurturing;opportunities, including for women to become trainers; body shape and strength; riskand danger; industry fashion and trends. The results from this study suggest women face discrimination in horseracing onaccount of a number of factors, the three main perceived reasons are due to theirphysical strength, body shape and the tradition and history embedded within theindustry. Whilst there is a shift starting to occur where more women are coming throughin flat racing, this is slow. Participants consider that women may find these barriers andperceptions held by others difficult to overcome, which may result in their inability toachieve equality in this sport. Given the exploratory character of the study, conclusionsare tentative and we propose a number of areas for further research

    ERIS: revitalising an adaptive optics instrument for the VLT

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    ERIS is an instrument that will both extend and enhance the fundamental diffraction limited imaging and spectroscopy capability for the VLT. It will replace two instruments that are now being maintained beyond their operational lifetimes, combine their functionality on a single focus, provide a new wavefront sensing module that makes use of the facility Adaptive Optics System, and considerably improve their performance. The instrument will be competitive with respect to JWST in several regimes, and has outstanding potential for studies of the Galactic Center, exoplanets, and high redshift galaxies. ERIS had its final design review in 2017, and is expected to be on sky in 2020. This contribution describes the instrument concept, outlines its expected performance, and highlights where it will most excel.Comment: 12 pages, Proc SPIE 10702 "Ground-Based and Airborne Instrumentation for Astronomy VII

    Simulating medium-spectral-resolution exoplanet characterization with SCALES angular/reference differential imaging

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    SCALES (Slicer Combined with Array of Lenslets for Exoplanet Spectroscopy) is a 2 - 5 micron high-contrast lenslet-based integral field spectrograph (IFS) designed to characterize exoplanets and their atmospheres. The SCALES medium-spectral-resolution mode uses a lenslet subarray with a 0.34 x 0.36 arcsecond field of view which allows for exoplanet characterization at increased spectral resolution. We explore the sensitivity limitations of this mode by simulating planet detections in the presence of realistic noise sources. We use the SCALES simulator scalessim to generate high-fidelity mock observations of planets that include speckle noise from their host stars, as well as other atmospheric and instrumental noise effects. We employ both angular and reference differential imaging as methods of disentangling speckle noise from the injected planet signals. These simulations allow us to assess the feasibility of speckle deconvolution for SCALES medium resolution data, and to test whether one approach outperforms another based on planet angular separations and contrasts

    A chemical survey of exoplanets with ARIEL

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    Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 ÎŒm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio

    Book of Ruth Session 1

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    In The Book of Ruth is a great love story, tremendous love story. But it\u27s really a great character builder, too. And I\u27d like to point out some of these attributes of the characters of this book with you

    Book of Ruth Session 2

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    Naomi, Ruth and Boa

    Book of Ruth Session 3

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    Quickly, so you don\u27t burn yourself on that candle if you have your Bibles handy, let\u27s turn to the Book of Ruth, Chapter two, where we left off yesterday morning. And we just introduced, as Ron Hayford said, the love story that Ruth and Boaz have meant and they\u27ve fallen in love with one another. But now, as you come to this love story section and the book ends, you see that there\u27s really a profound love story between God and the reader of this book, and that the story of these two people are nothing more than a bigger picture for what God has for you