42 research outputs found

    The 3D Structure of N132D in the LMC: A Late-Stage Young Supernova Remnant

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    We have used the Wide Field Spectrograph (WiFeS) on the 2.3m telescope at Siding Spring Observatory to map the [O III] 5007{\AA} dynamics of the young oxygen-rich supernova remnant N132D in the Large Magellanic Cloud. From the resultant data cube, we have been able to reconstruct the full 3D structure of the system of [O III] filaments. The majority of the ejecta form a ring of ~12pc in diameter inclined at an angle of 25 degrees to the line of sight. We conclude that SNR N132D is approaching the end of the reverse shock phase before entering the fully thermalized Sedov phase of evolution. We speculate that the ring of oxygen-rich material comes from ejecta in the equatorial plane of a bipolar explosion, and that the overall shape of the SNR is strongly influenced by the pre-supernova mass loss from the progenitor star. We find tantalizing evidence of a polar jet associated with a very fast oxygen-rich knot, and clear evidence that the central star has interacted with one or more dense clouds in the surrounding ISM.Comment: Accepted for Publication in Astrophysics & Space Science, 18pp, 8 figure

    An Observational Overview of Solar Flares

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    We present an overview of solar flares and associated phenomena, drawing upon a wide range of observational data primarily from the RHESSI era. Following an introductory discussion and overview of the status of observational capabilities, the article is split into topical sections which deal with different areas of flare phenomena (footpoints and ribbons, coronal sources, relationship to coronal mass ejections) and their interconnections. We also discuss flare soft X-ray spectroscopy and the energetics of the process. The emphasis is to describe the observations from multiple points of view, while bearing in mind the models that link them to each other and to theory. The present theoretical and observational understanding of solar flares is far from complete, so we conclude with a brief discussion of models, and a list of missing but important observations.Comment: This is an article for a monograph on the physics of solar flares, inspired by RHESSI observations. The individual articles are to appear in Space Science Reviews (2011

    Measuring Success in Family Businesses: The Concept of Configurational Fit

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    The problems associated with measuring success in small businesses are primarily caused by a lack of comparable data due to the ambiguity of success and by subjective biases. Success evaluation is dominated by the estimates of business owners, who tend to overestimate overall success and internal strengths. However, reliable success measurement instruments would be useful for small business owners/managers as well as small business policymakers. The main purposes of this article are to compare various measures of success, to explore the differences in their outcomes, and to analyze whether a model of success measurement using configurational fit can be used to overcome subjective biases. The study is based on a recent survey of 103 small family-owned businesses in the eastern Austrian border region. Our analysis of the data confirmed the existence of the measurement problems mentioned above. While some individual indicators show significant biases as well as effects due to company age, size and industry, the aggregated indicator based on the concept of configurational fit seems to be an appropriate means of overcoming most of these drawbacks.(author's abstract
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