31 research outputs found

    Models of gravitational lens candidates from Space Warps CFHTLS

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    We report modelling follow-up of recently-discovered gravitational-lens candidates in the Canada France Hawaii Telescope Legacy Survey. Lens modelling was done by a small group of specially-interested volunteers from the SpaceWarps citizen-science community who originally found the candidate lenses. Models are categorised according to seven diagnostics indicating (a) the image morphology and how clear or indistinct it is, (b) whether the mass map and synthetic lensed image appear to be plausible, and (c) how the lens-model mass compares with the stellar mass and the abundance-matched halo mass. The lensing masses range from ~10^11 Msun to >10^13 Msun. Preliminary estimates of the stellar masses show a smaller spread in stellar mass (except for two lenses): a factor of a few below or above ~10^11 Msun. Therefore, we expect the stellar-to-total mass fraction to decline sharply as lensing mass increases. The most massive system with a convincing model is J1434+522 (SW05). The two low-mass outliers are J0206-095 (SW19) and J2217+015 (SW42); if these two are indeed lenses, they probe an interesting regime of very low star-formation efficiency. Some improvements to the modelling software (SpaghettiLens), and discussion of strategies regarding scaling to future surveys with more and frequent discoveries, are included.Comment: 16 pages, 10 figures, 1 table, online supplement table_1.csv contains additional detailed numbers shown in table 1 and figure

    Money, (Co)Production and Power in Digital

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    This article discusses the contribution of critical political economy approaches to digital journalism studies and argues that these offer important correctives to celebratory perspectives. The first part offers a review and critique of influential claims arising from self-styled new studies of convergence culture, media and creative industries. The second part discusses the contribution of critical political economy in examining digital journalism and responding to celebrant claims. The final part reflects on problems of restrictive normativity and other limitations within media political economy perspectives and considers ways in which challenges might be addressed by more synthesising approaches. The paper proposes developing radical pluralist, media systems and comparative analysis, and advocates drawing on strengths in both political economy and culturalist traditions to map and evaluate practices across all sectors of digital journalism

    Reflections on the ascendancy of technology in the media and its implications for organisations and their leaders.

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    Technology is placing new demands on the media industry. Creative output is no longer simply the content itself, but the ‘containers’ in which it appears. Media industry leaders and practitioners must now understand the strategic importance of technology in all its dimensions. Yet more than this, they must be able to make the necessary – and often difficult – adjustments inside organisations. This essay draws on two exploratory research projects into technology transitions in the media industry. The findings suggest the ascendancy of technology does not necessitate a diminution in the importance of creative content. However, it does raise two key challenges: first, a need for new ‘editorial-technological’ competencies, and second, a shift in media workplace culture to recognise the equivalency in importance between classic media creative skills and the newer but equally intellectually demanding tech-media skills

    Innovators in Digital News

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    News organisations are struggling with technology transitions and fearful for their future. Yet a cadre of these institutions – some new, some old – has emerged who are succeeding with digital news. Why are Vice and BuzzFeed investing in journalism and why are pedigree journalists joining them? Why are established news organisations letting experienced journalists go but recruiting technologists? This book looks at several key players in the digital news industry – including the Guardian, the New York Times, Quartz, BuzzFeed and Vice – and draws on extensive first-hand research inside the organisations. How do they operate? How do they innovate? This book identifies and discusses the common elements that underlie their success, and provides valuable pointers for how all players, legacy and clean sheet, can seize the growth potential that digital markets present.</p

    Strategisches Management und Nachhaltigkeit in den Medien – Erkenntnisse aus Theorie und Praxis

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