5 research outputs found

    Dynamics of Coronal Bright Points as seen by Sun Watcher using Active Pixel System detector and Image Processing (SWAP), Atmospheric Imaging Assembly AIA), and Helioseismic and Magnetic Imager (HMI)

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    The \textit{Sun Watcher using Active Pixel system detector and Image Processing}(SWAP) on board the \textit{PRoject for OnBoard Autonomy\todash 2} (PROBA\todash 2) spacecraft provides images of the solar corona in EUV channel centered at 174 \AA. These data, together with \textit{Atmospheric Imaging Assembly} (AIA) and the \textit{Helioseismic and Magnetic Imager} (HMI) on board \textit{Solar Dynamics Observatory} (SDO), are used to study the dynamics of coronal bright points. The evolution of the magnetic polarities and associated changes in morphology are studied using magnetograms and multi-wavelength imaging. The morphology of the bright points seen in low-resolution SWAP images and high-resolution AIA images show different structures, whereas the intensity variations with time show similar trends in both SWAP 174 and AIA 171 channels. We observe that bright points are seen in EUV channels corresponding to a magnetic-flux of the order of 101810^{18} Mx. We find that there exists a good correlation between total emission from the bright point in several UV\todash EUV channels and total unsigned photospheric magnetic flux above certain thresholds. The bright points also show periodic brightenings and we have attempted to find the oscillation periods in bright points and their connection to magnetic flux changes. The observed periods are generally long (10\todash 25 minutes) and there is an indication that the intensity oscillations may be generated by repeated magnetic reconnection

    Selling displaced people? A multi‐method study of the public communication strategies of international refugee organisations

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    Since 2011, the world has faced a major increase in forced displacement (UNHCR, 2017). As a growing number of states implement restrictive refugee policies, public communication has become essential for refugee organizations (Dijkzeul & Moke, 2005). Therefore, we have examined three international refugee organizations’ discursive strategies towards the Syrian crisis, and their production and social context. A critical discourse analysis of international press releases (N=122) and six semi-structured interviews with press and regional officers have shown that the observed organizations largely dehumanize displaced people and subordinate them to the ‘Western self’ and state interests. Displaced people hardly obtain their own voice. First, press releases’ medium characteristics and the importance of media attention result in a depersonalising humanitarian discourse. Second, we found indications of a post-humanitarian discourse reproducing the humanitarian sector’s ‘marketization’. Third, the examined organizations use the political realist cross-issue persuasion strategy, displaying displaced people as resettlement objects
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