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China’s rise in a liberal world order in transition – introduction to the FORUM
In a time of great uncertainty about the future and resilience of the liberal world order this Forum focuses on China’s rise and interplay with the foundations of that liberal order. The key question is the extent to and variegated ways in which China - with its (re)ascendance to power and potential global leadership – is adapting to and perhaps even strengthening liberal institutions and rules of the game, confronting them, or developing alternative paths. In this introduction to the Forum we advance three key points based on the contributions. First, contrasting the orthodox binary scenarios of either inevitable conflict or co-optation offered in the mainstream IR debate, the Forum highlights the possibility of a third scenario of China’s interplay with the liberal world and its key actors, institutions, and rules. A hybrid and variegated scenario that entails both conflict and adaptation, differently entangled in different issue areas. Second, it stresses the need to conceptualize and empirically comprise the essentially interlinked nature of domestic state-society models and the global political economy. Third, we argue for a perspective that incorporates underlying economic and social structures and the power relations embedded therein
Dusty tails of evaporating exoplanets. II. Physical modelling of the KIC 12557548b light curve
Evaporating rocky exoplanets, such as KIC 12557548b, eject large amounts of
dust grains, which can trail the planet in a comet-like tail. When such objects
occult their host star, the resulting transit signal contains information about
the dust in the tail. We aim to use the detailed shape of the Kepler light
curve of KIC 12557548b to constrain the size and composition of the dust grains
that make up the tail, as well as the mass loss rate of the planet. Using a
self-consistent numerical model of the dust dynamics and sublimation, we
calculate the shape of the tail by following dust grains from their ejection
from the planet to their destruction due to sublimation. From this dust cloud
shape, we generate synthetic light curves (incorporating the effects of
extinction and angle-dependent scattering), which are then compared with the
phase-folded Kepler light curve. We explore the free-parameter space thoroughly
using a Markov chain Monte Carlo method. Our physics-based model is capable of
reproducing the observed light curve in detail. Good fits are found for initial
grain sizes between 0.2 and 5.6 micron and dust mass loss rates of 0.6 to 15.6
M_earth/Gyr (2-sigma ranges). We find that only certain combinations of
material parameters yield the correct tail length. These constraints are
consistent with dust made of corundum (Al2O3), but do not agree with a range of
carbonaceous, silicate, or iron compositions. Using a detailed, physically
motivated model, it is possible to constrain the composition of the dust in the
tails of evaporating rocky exoplanets. This provides a unique opportunity to
probe to interior composition of the smallest known exoplanets.Comment: 18 pages, 11 figures, A&A accepte
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