84 research outputs found
Extracting urban deprivation indicators using superspectral very-high-resolution satellite imagery
The SOPHIE search for northern extrasolar planets: VI. Three new hot Jupiters in multi-planet extrasolar systems
We present high-precision radial-velocity measurements of three solar-type
stars: HD 13908, HD 159243, and HIP 91258. The observations were made with the
SOPHIE spectrograph at the 1.93-m telescope of Observatoire de Haute-Provence
(France). They show that these three bright stars host exoplanetary systems
composed of at least two companions. HD 13908 b is a planet with a minimum mass
of 0.865+-0.035 Mjup, on a circular orbit with a period of 19.382+-0.006 days.
There is an outer massive companion in the system with a period of 931+-17
days, e = 0.12+-0.02, and a minimum mass of 5.13+-0.25 Mjup. The star HD
159243, also has two detected companions with respective masses, periods, and
eccentricities of Mp = 1.13+-0.05 and 1.9+-0.13 Mjup, = 12.620+-0.004 and
248.4+-4.9 days, and e = 0.02+-0.02 and 0.075+-0.05. Finally, the star HIP
91258 has a planetary companion with a minimum mass of 1.068+-0.038 Mjup, an
orbital period of 5.0505+-0.0015 days, and a quadratic trend indicating an
outer planetary or stellar companion that is as yet uncharacterized. The
planet-hosting stars HD 13908, HD 159243, and HIP 91258 are main-sequence stars
of spectral types F8V, G0V, and G5V, respectively, with moderate activity
levels. HIP 91258 is slightly over-metallic, while the two other stars have
solar-like metallicity. The three systems are discussed in the frame of
formation and dynamical evolution models of systems composed of several giant
planets.Comment: accepted in A&
SOPHIE velocimetry of Kepler transit candidates. V. The three hot Jupiters KOI-135b, KOI-204b and KOI-203b (alias Kepler-17b)
We report the discovery of two new transiting hot Jupiters, KOI-135b and
KOI-204b, that were previously identified as planetary candidates by Borucki et
al. 2011, and, independently of the Kepler team, confirm the planetary nature
of Kepler-17b, recently announced by Desert et al. 2011. Radial-velocity
measurements, taken with the SOPHIE spectrograph at the OHP, and Kepler
photometry (Q1 and Q2 data) were used to derive the orbital, stellar and
planetary parameters. KOI-135b and KOI-204b orbit their parent stars in 3.02
and 3.25 days, respectively. They have approximately the same radius,
Rp=1.20+/-0.06 R_jup and 1.24+/-0.07 R_jup, but different masses Mp=3.23+/-0.19
M_jup and 1.02+/-0.07 M_jup. As a consequence, their bulk densities differ by a
factor of four, rho_p=2.33+/-0.36 g.cm^-3 (KOI-135b) and 0.65+/-0.12 g.cm-3
(KOI-204b). Our SOPHIE spectra of Kepler-17b, used both to measure the
radial-velocity variations and determine the atmospheric parameters of the host
star, allow us to refine the characterisation of the planetary system. In
particular we found the radial-velocity semi-amplitude and the stellar mass to
be respectively slightly smaller and larger than Desert et al. These two
quantities, however, compensate and lead to a planetary mass fully consistent
with Desert et al.: our analysis gives Mp=2.47+/-0.10 M_jup and Rp=1.33+/-0.04
R_jup. We found evidence for a younger age of this planetary system, t<1.8 Gyr,
which is supported by both evolutionary tracks and gyrochronology. Finally, we
confirm the detection of the optical secondary eclipse and found also the
brightness phase variation with the Q1 and Q2 Kepler data. The latter indicates
a low redistribution of stellar heat to the night side (<16% at 1-sigma), if
the optical planetary occultation comes entirely from thermal flux. The
geometric albedo is A_g<0.12 (1-sigma).Comment: submitted to Astronomy and Astrophysic
SOPHIE velocimetry of Kepler transit candidates XII. KOI-1257 b: a highly eccentric three-month period transiting exoplanet
In this paper we report a new transiting warm giant planet: KOI-1257 b. It
was first detected in photometry as a planet-candidate by the
space telescope and then validated thanks to a radial velocity follow-up with
the SOPHIE spectrograph. It orbits its host star with a period of 86.647661 d
3 s and a high eccentricity of 0.772 0.045. The planet transits the
main star of a metal-rich, relatively old binary system with stars of mass of
0.99 0.05 Msun and 0.70 0.07 Msun for the primary and secondary,
respectively. This binary system is constrained thanks to a self-consistent
modelling of the transit light curve, the SOPHIE radial
velocities, line bisector and full-width half maximum (FWHM) variations, and
the spectral energy distribution. However, future observations are needed to
confirm it. The PASTIS fully-Bayesian software was used to validate the nature
of the planet and to determine which star of the binary system is the transit
host. By accounting for the dilution from the binary both in photometry and in
radial velocity, we find that the planet has a mass of 1.45 0.35 Mjup,
and a radius of 0.94 0.12 Rjup, and thus a bulk density of 2.1
1.2 g.cm. The planet has an equilibrium temperature of 511 50 K,
making it one of the few known members of the warm-jupiter population. The
HARPS-N spectrograph was also used to observe a transit of KOI-1257 b,
simultaneously with a joint amateur and professional photometric follow-up,
with the aim of constraining the orbital obliquity of the planet. However, the
Rossiter-McLaughlin effect was not clearly detected, resulting in poor
constraints on the orbital obliquity of the planet.Comment: 39 pages, 17 figures, accepted for publication in Astronomy &
Astrophysic
Rethinking “democratic backsliding” in Central and Eastern Europe – looking beyond Hungary and Poland
This essay introduces contributions to a special issue of East European Politics on “Rethinking democratic backsliding in Central and Eastern Europe”, which seeks to expand the study of democratic regression in CEE beyond the paradigmatic cases of Hungary and Poland. Reviewing these contributions, we identify several directions for research: 1) the need to critique “democratic backsliding”, not simply as a label, but also as an assumed regional trend; 2) a need to better integrate the role of illiberal socio-economic structures such as oligarchical structures or corrupt networks; and 3) a need to (re-)examine the trade-offs between democratic stability and democratic quality. We also note how insights developed researching post-communist regions such as Western Balkans or the post-Soviet space could usefully inform work on CEE backsliding. We conclude by calling for the study of CEE democracy to become more genuinely interdisciplinary, moving beyond some narrowly institutionalist comparative political science assumptions
WASP-113b and WASP-114b, two inflated hot Jupiters with contrasting densities
Aims. We present the discovery and characterisation of the exoplanets WASP-113b and WASP-114b by the WASP surveys, SOPHIE and CORALIE. Methods. The planetary nature of the systems was established by performing follow-up photometric and spectroscopic observations. The follow-up data were combined with the WASP-photometry and analysed with an MCMC code to obtain system parameters. Results. The host stars WASP-113 and WASP-114 are very similar. They are both early G-type stars with an effective temperature of ~5900 K, [Fe/H] ~ 0.12, and log g~ 4.1 dex. However, WASP-113 is older than WASP-114. Although the planetary companions have similar radii, WASP-114b is almost four times heavier than WASP-113b. WASP-113b has a mass of 0.48 MJup and an orbital period of ~4.5 days; WASP-114b has a mass of 1.77 MJup and an orbital period of ~1.5 days. Both planets have inflated radii, in particular WASP-113 with a radius anomaly of ℜ = 0.35. The high scale height of WASP-113b (~950 km) makes it a good target for follow-up atmospheric observations.Publisher PDFPeer reviewe
Spin-orbit inclinations of the exoplanetary systems HAT-P-8, HAT-P-9, HAT-P-16 and HAT-P-23
We report the measurement of the spin-orbit angle of the extra-solar planets
HAT-P-8 b, HAT-P-9 b, HAT-P-16 b and HAT-P-23 b, thanks to spectroscopic
observations performed at the Observatoire de Haute-Provence with the SOPHIE
spectrograph on the 1.93-m telescope. Radial velocity measurements of the
Rossiter-McLaughlin effect show the detection of an apparent prograde, aligned
orbit for all systems. The projected spin-orbit angles are found to be
lambda=-17 deg (+9.2,-11.5), -16 deg (8), -10 deg (16), +15 deg (22) for
HAT-P-8, HAT-P-9, HAT-P-16 and HAT-P-23 respectively, with corresponding
projected rotational velocities of 14.5 (0.8), 12.5 (1.8), 3.9 (0.8), and 7.8
(1.6) km/s. These new results increase to 37 the number of accurately measured
spin-orbit angles in transiting extrasolar systems. We conclude by drawing a
tentative picture of the global behaviour of orbital alignement, involving the
complexity and diversity of possible mechanisms.Comment: accepted in A&
Organizing for impact: International organizations and global pension policy
The internal dynamics and politics of international organizations influence how international policy agendas are set and how effectively they are pursued. International organizations are open systems which respond and adapt to the external policy environment in order to remain relevant to global policymaking. Through an analysis of the internal politics of the World Bank and International Labour Organization, the leading global agenda-setters for pension reform, this article shows that internal political battles and restructuring have a decisive influence on global pensions policy. Appointment of key personnel and internal reorganization can help make certain policy ideas prominent over others. Scholars should pay greater attention to processes of change within international organizations in order to better understand the international agenda setting process
Creating Outsiders: Silent Non-Exit, Broken Voice, and Political Anomie Through Post-Communist Social Policy
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