1,011,904 research outputs found
Solar Physics and the Solar-Stellar Connection at Dome C
Solar magnetic fields evolve on many time-scales, e.g., the generation,
migration, and dissipation of magnetic flux during the 22-year magnetic cycle
of the Sun. Active regions develop and decay over periods of weeks. The
build-up of magnetic shear in active regions can occur within less than a day.
At the shortest time-scales, the magnetic field topology can change rapidly
within a few minutes as the result of eruptive events such as flares, filament
eruptions, and coronal mass ejections. The unique daytime seeing
characteristics at Dome C, i.e., continuous periods of very good to excellent
seeing during almost the entire Antarctic summer, allow us to address many of
the top science cases related to the evolution of solar magnetic fields. We
introduce the Advanced Solar Photometric Imager and Radiation Experiment and
present the science cases for synoptic solar observations at Dome C.
Furthermore, common science cases concerning the solar-stellar connection are
discussed in the context of the proposed International Concordia Explorer
Telescope.Comment: 8 pages, 2 b/w figures, submitted to 2nd ARENA Conference on "The
Astrophysical Science Cases at Dome C'', H. Zinnecker, H. Rauer, and N.
Epchtein (eds.), EAS Publications Serie
The rhetoric of “science diplomacy": Innovation for the EU's scientific cooperation? EL-CSID Working Paper Issue 2018/16 • April 2018
In the recent years, the EU policy discourse has endorsed the notion of “science diplomacy” that
points to the interaction between scientific research and foreign policy as instrumental in the societal
and political progress. Commissioner for science, research and innovation Carlos Moedas is
particularly keen on seeing “the EU play an increasingly active and visible role in international science
diplomacy” (Moedas, 2016). In doing so, the EU is part of, and perhaps leading among, those global
actors that have jumped on the “science diplomacy” bandwagon, where the activities concerned with
scientific cooperation (such as part of the work by UNESCO or The World Academy of Sciences –
TWAS) are framed as “science diplomacy”
The Collective Consciousness of Information Technology Research: Ways of seeing Information Technology Research: Its Objects and Territories
The collective consciousness of effective groups of researchers is characterised by shared understandings of their research object or territory. In the relatively new field of information technology research, rapid expansion and fragmentation of the territory has led to different perceptions about what constitutes information technology research. This project explores a facet of the collective consciousness of disparate groups of researchers and lays a foundation for constructing shared research objects. Making IT researchers’ ways of seeing explicit may help us understand some of the complexities associated with inter and intra disciplinary collaboration amongst research groups, and the complexities associated with technology transfer to industry. This report analyses IT research, its objects and territories, as they are constituted by IT researchers associated with the sub-disciplines of information systems, computer science and information security. A phenomenographic approach is used to elicit data from a diverse range of IT researchers in semistructured interviews. This data is analysed to show (1) the variation in meaning associated with the idea of IT research and (2) the awareness structures through which participants experience variation in ways of seeing the object and territories of IT research. An Outcome Space represents the interrelation between different ways of seeing the territory. Eight ways of seeing IT research, its objects and territories, were found: The Technology Conception, The Information Conception, The Information and Technology Conception, The Communication Conception, The Ubiquitous Conception, The Sanctioned Conception, The Dialectic Conception and The Constructed Conception. These are described in detail and illustrated with participants’ quotes. Finally, some recommendations for further research are made
Laser-only adaptive optics achieves significant image quality gains compared to seeing-limited observations over the entire sky
Adaptive optics laser guide star systems perform atmospheric correction of
stellar wavefronts in two parts: stellar tip-tilt and high-spatial-order
laser-correction. The requirement of a sufficiently bright guide star in the
field-of-view to correct tip-tilt limits sky coverage. Here we show an
improvement to effective seeing without the need for nearby bright stars,
enabling full sky coverage by performing only laser-assisted wavefront
correction. We used Robo-AO, the first robotic AO system, to comprehensively
demonstrate this laser-only correction. We analyze observations from four years
of efficient robotic operation covering 15,000 targets and 42,000 observations,
each realizing different seeing conditions. Using an autoguider (or a
post-processing software equivalent) and the laser to improve effective seeing
independent of the brightness of a target, Robo-AO observations show a 39+/-19%
improvement to effective FWHM, without any tip-tilt correction. We also
demonstrate that 50% encircled-energy performance without tip-tilt correction
remains comparable to diffraction-limited, standard Robo-AO performance.
Faint-target science programs primarily limited by 50% encircled-energy (e.g.
those employing integral field spectrographs placed behind the AO system) may
see significant benefits to sky coverage from employing laser-only AO.Comment: Accepted for publication in The Astronomical Journal. 7 pages, 6
figure
PILOT: design and capabilities
The proposed design for PILOT is a general-purpose, wide-field 1 degree 2.4m,
f/10 Ritchey-Chretien telescope, with fast tip-tilt guiding, for use 0.5-25
microns. The design allows both wide-field and diffraction-limited use at these
wavelengths. The expected overall image quality, including median seeing, is
0.28-0.3" FWHM from 0.8-2.4 microns. Point source sensitivities are estimated.Comment: 4 pages, Proceedings of 2nd ARENA conference 'The Astrophysical
Science Cases at Dome C', Potsdam, 17-21 September 200
Plant capitalism and company science: the Indian career of Nathaniel Wallich
The career of the Danish-born botanist Nathaniel Wallich, superintendent of the Calcutta Botanic Garden from 1815 to 1846, illustrates the complex nature of botanical science under the East India Company and shows how the plant life of South Asia was used as a capital resource both in the service of the Company's economic interests and for Wallich's own professional advancement and international reputation. Rather than seeing him as a pioneer of modern forest conservation or an innovative botanist, Wallich's attachment to the ideology of ‘improvement’ and the Company's material needs better explain his longevity as superintendent of the Calcutta garden. Although aspects of Wallich's career and botanical works show the importance of circulation between Europe and India, more significant was the hierarchy of knowledge in which indigenous plant lore and illustrative skill were subordinated to Western science and in which colonial science frequently lagged behind that of the metropolis
Seeing, Wind and Outer Scale Effects on Image Quality at the Magellan Telescopes
We present an analysis of the science image quality obtained on the twin 6.5
metre Magellan telescopes over a 1.5 year period, using images of ~10^5 stars.
We find that the telescopes generally obtain significantly better image quality
than the DIMM-measured seeing. This is qualitatively consistent with
expectations for large telescopes, where the wavefront outer scale of the
turbulence spectrum plays a significant role. However, the dominant effect is
found to be wind speed with Magellan outperforming the DIMMs most markedly when
the wind is strongest. Excluding data taken during strong wind conditions (>10
m/s), we find that the Magellan telescopes still significantly outperform the
DIMM seeing, and we estimate the site to have L_0 ~ 25 m on average. We also
report on the first detection of a negative bias in DIMM data. This is found to
occur, as predicted, when the DIMM is affected by certain optical aberrations
and the turbulence profile is dominated by the upper layers of the atmosphere.Comment: Accepted for publication in PASP. 10 pages, 12 figures
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