Aperture Increase Options for the Dutch Open Telescope

This paper is an invitation to the international community to participate in the usage and a substantial upgrade of the Dutch Open Telescope on La Palma (DOT, \url{http://dot.astro.uu.nl}). We first give a brief overview of the approach, design, and current science capabilities of the DOT. The DOT database (\url{http://dotdb.phys.uu.nl/DOT}) now contains many tomographic image sequences with 0.2-0.3 arcsec resolution and up to multi-hour duration. You are welcome to pull them over for analysis. The main part of this contribution outlines DOT upgrade designs implementing larger aperture. The motivation for aperture increase is the recognition that optical solar physics needs the substantially larger telescope apertures that became useful with the advent of adaptive optics and viable through the DOT's open principle, both for photospheric polarimetry at high resolution and high sensitivity and for chromospheric fine-structure diagnosis at high cadence and full spectral sampling. Realization of an upgrade requires external partnership(s). This report about DOT upgrade options therefore serves also as initial documentation for potential partners.Comment: in press,"Physics of Chromospheric Plasmas" (Coimbra), ASP 368, 573 (2007

Populist communication in the new media environment: a cross-regional comparative perspective

The changing terms of mediation place new demands, opportunities and risks on the performance of the political persona. Visibility has become a double-edged sword, leaving representatives vulnerable to exposure while new tools provide opportunities for emerging entrepreneurial actors. This double risk to elites’ mediated personas—exposure and challenge from entrepreneurs—renders their armour of authenticity dangerously fragile, which nourishes a public sense of being inefficaciously represented. It is this climate in which populism currently flourishes around the globe. Three primary criteria of mediated self-representation by politicians—visibility, authenticity and efficacy—form the focus of this paper: how do populists negotiate such demands in different democratic contexts, and wherein lies the symbiosis between populism and the new media environment suggested by the literature? To answer this, the paper compares two populist cases responding to different democratic contexts: UKIP, a right-wing party from an established democracy (UK), and the Economic Freedom Fighters (EFF), a left-wing party from a transitional democracy (South Africa). The objects of study are disruptive performances by these parties, which are considered emblematic manifestations of populist ideology as they establish a Manichaean relationship between the elite and populist actors who embody the people. The paper introduces disruption as a multi-faceted and significant analytical concept to explain the populist behaviour and strategies that underlie populist parties’ responses to the demands for visibility, authenticity and efficacy that the new media environment places upon political representatives. Using mixed methods with an interpretive focus, the paper paints a rich picture of the contexts, meanings and means of construction of populist performances

The European Solar Telescope

The European Solar Telescope (EST) is a project aimed at studying the magnetic connectivity of the solar atmosphere, from the deep photosphere to the upper chromosphere. Its design combines the knowledge and expertise gathered by the European solar physics community during the construction and operation of state-of-the-art solar telescopes operating in visible and near-infrared wavelengths: the Swedish 1m Solar Telescope, the German Vacuum Tower Telescope and GREGOR, the French Télescope Héliographique pour l'Étude du Magnétisme et des Instabilités Solaires, and the Dutch Open Telescope. With its 4.2 m primary mirror and an open configuration, EST will become the most powerful European ground-based facility to study the Sun in the coming decades in the visible and near-infrared bands. EST uses the most innovative technological advances: the first adaptive secondary mirror ever used in a solar telescope, a complex multi-conjugate adaptive optics with deformable mirrors that form part of the optical design in a natural way, a polarimetrically compensated telescope design that eliminates the complex temporal variation and wavelength dependence of the telescope Mueller matrix, and an instrument suite containing several (etalon-based) tunable imaging spectropolarimeters and several integral field unit spectropolarimeters. This publication summarises some fundamental science questions that can be addressed with the telescope, together with a complete description of its major subsystems

The European Solar Telescope

The European Solar Telescope (EST) is a project aimed at studying the magnetic connectivity of the solar atmosphere, from the deep photosphere to the upper chromosphere. Its design combines the knowledge and expertise gathered by the European solar physics community during the construction and operation of state-of-the-art solar telescopes operating in visible and near-infrared wavelengths: the Swedish 1m Solar Telescope, the German Vacuum Tower Telescope and GREGOR, the French Télescope Héliographique pour l’Étude du Magnétisme et des Instabilités Solaires, and the Dutch Open Telescope. With its 4.2 m primary mirror and an open configuration, EST will become the most powerful European ground-based facility to study the Sun in the coming decades in the visible and near-infrared bands. EST uses the most innovative technological advances: the first adaptive secondary mirror ever used in a solar telescope, a complex multi-conjugate adaptive optics with deformable mirrors that form part of the optical design in a natural way, a polarimetrically compensated telescope design that eliminates the complex temporal variation and wavelength dependence of the telescope Mueller matrix, and an instrument suite containing several (etalon-based) tunable imaging spectropolarimeters and several integral field unit spectropolarimeters. This publication summarises some fundamental science questions that can be addressed with the telescope, together with a complete description of its major subsystems

Aperture Increase Options for the Dutch Open Telescope

Abstract. This paper is an invitation to the international community to participate in the usage and a substantial upgrade of the Dutch Open Telescope on La Palma (DOT