We report the discovery by the CoRoT satellite of a new transiting giant planet in a 2.83 days orbit about a V = 15.5 solar analog star (M * = 1.08± 0.08 M , R * = 1.1± 0.1 R , T eff = 5675± 80 K). ...This new planet, CoRoT-12b, has a mass of 0.92± 0.07 M Jup and a radius of 1.44± 0.13 R Jup. Its low density can be explained by standard models for irradiated planets.
Close-in extrasolar planets experience extreme tidal interactions with their host stars. This may lead to a reduction of the planetary radius and a spin-up of stellar rotation. Tidal interactions ...have been computed for a number of extrasolar planets in circular orbits within 0.06 AU, namely for OGLE-TR-56 b. We compare our range of the tidal dissipation value with two dissipation models from Sasselov (CITE) and conclude that our choices are equivalent to these models. However, applied to the planet OGLE-TR-56 b, we find in contrast to Sasselov (CITE) that this planet will spiral-in toward the host star in a few billion years. We show that the average and maximum value of our range of dissipation are equivalent to the linear and quadratic dissipation models of Sasselov (CITE). Due to limitations in the observational techniques, we do not see a possibility to distinguish between the two dissipation models as outlined by Sasselov (CITE). OGLE-TR-56 b may therefore not be well suited to serve as a test case for dissipation models. The probable existence of OGLE-TR-3 b at 0.02 AU and the discovery of OGLE-TR-113 b at 0.023 AU and OGLE-TR-132 b at 0.03 AU may also counter Sasselovs (CITE) assumption of a pile-up stopping boundary at 0.04 AU.
In this paper, the CoRoT ExoplanetScience Team announces its 14th discovery. Herein, we discuss the observations and analyses that allowed us to derive the parameters of this system: a hot Jupiter ...with a mass of 7.6 ± 0.6 Jupiter masses orbiting a solar-type star (F9V) with a period of only 1.5 d, less than 5 stellar radii from its parent star. It is unusual for such a massive planet to have such a small orbit: only one other known higher mass exoplanet orbits with a shorter period. The CoRoT space mission, launched on December 27, 2006, has been developed and is operated by the CNES, with the contribution of Austria, Belgium, Brazil, ESA (RSSD and Science Program), Germany and Spain.
Aims: We report the discovery of CoRoT-16b, a low density hot jupiter that orbits a faint G5V star (mV = 15.63) in 5.3523 ± 0.0002 days with slight eccentricity. A fit of the data with no a priori ...assumptions on the orbit leads to an eccentricity of 0.33 ± 0.1. We discuss this value and also derive the mass and radius of the planet. Methods: We analyse the photometric transit curve of CoRoT-16 given by the CoRoT satellite, and radial velocity data from the HARPS and HIRES spectrometers. A combined analysis using a Markov chain Monte Carlo algorithm is used to get the system parameters. Results: CoRoT-16b is a 0.535 -0.083/+0.085 MSUBJ/SUB, 1.17 -0.14/+0.16 RSUBJ/SUB hot Jupiter with a density of 0.44 -0.14/+0.21 g cmSUP-3/SUP. Despite its short orbital distance (0.0618 ± 0.0015 AU) and the age of the parent star (6.73 ± 2.8 Gyr), the planet orbit exhibits significantly non-zero eccentricity. This is very uncommon for this type of objects as tidal effects tend to circularise the orbit. This value is discussed taking into account the characteristics of the star and the observation accuracy. The CoRoT space mission, launched on December 27, 2006, has been developed and is operated by the CNES with the contribution of Austria, Belgium, Brasil, ESA, Germany, and Spain.Observations made with the HARPS spectrograph at ESO La Silla Observatory (HARPS programs 083.C-0186 and 184.C-0639) and the HIRES spectrograph at the Keck Observatory (NASA-Keck programs N035Hr, N143Hr and N095Hr).
Context. CoRoT is a pioneering space mission devoted to the analysis of stellar variability and the photometric detection of extrasolar planets. Aims. We present the list of planetary transit ...candidates detected in the first field observed by CoRoT, IRa01, the initial run toward the Galactic anticenter, which lasted for 60 days. Methods. We analysed 3898 sources in the coloured bands and 5974 in the monochromatic band. Instrumental noise and stellar variability were taken into account using detrending tools before applying various transit search algorithms. Results. Fifty sources were classified as planetary transit candidates and the most reliable 40 detections were declared targets for follow-up ground-based observations. Two of these targets have so far been confirmed as planets, CoRoT-1b and CoRoT-4b, for which a complete characterization and specific studies were performed.
K2-141 b is a transiting, small (1.5
R
⊕
) ultra-short-period (USP) planet discovered by the
Kepler
space telescope orbiting a K-dwarf host star every 6.7 h. The planet's high surface temperature of ...more than 2000 K makes it an excellent target for thermal emission observations. Here we present 65 h of continuous photometric observations of K2-141 b collected with
Spitzer's
Infrared Array Camera (IRAC) Channel 2 at 4.5 μm spanning ten full orbits of the planet. We measured an infrared eclipse depth of ${f_{{{\rm{p}} \mathord{\left/ {\vphantom {{\rm{p}} {{{\rm{f}}_{\rm{*}}} \right. \kern-\nulldelimiterspace} {{{\rm{f}}_{\rm{*}}} = 142.9_{ - 39.0}^{38.5}$ ppm and a peak to trough amplitude variation of $A = 120.6_{ - 43.0}^{42.3}$ ppm. The best fit model to the
Spitzer
data shows no significant thermal hotspot offset, in contrast to the previously observed offset for the well-studied USP planet 55 Cnc e. We also jointly analyzed the new
Spitzer
observations with the photometry collected by
Kepler
during two separate K2 campaigns. We modeled the planetary emission with a range of toy models that include a reflective and a thermal contribution. With a two-temperature model, we measured a dayside temperature of ${T_{{\rm{p,d}}} = 2049_{ - 359}^{362}$ K and a night-side temperature that is consistent with zero (
T
p,n
< 1712 K at 2
σ
). Models with a steep dayside temperature gradient provide a better fit to the data than a uniform dayside temperature (ΔBIC = 22.2). We also found evidence for a nonzero geometric albedo ${A_{\rm{g}}} = 0.282_{ - 0.078}^{0.070}$. We also compared the data to a physically motivated, pseudo-2D rock vapor model and a 1D turbulent boundary layer model. Both models fit the data well. Notably, we found that the optical eclipse depth can be explained by thermal emission from a hot inversion layer, rather than reflected light. A thermal inversion may also be responsible for the deep optical eclipse observed for another USP, Kepler-10 b. Finally, we significantly improved the ephemerides for K2-141 b and c, which will facilitate further follow-up observations of this interesting system with state-of-the-art observatories such as
James Webb
Space Telescope.
The Berlin Exoplanet Search Telescope (BEST) wide-angle telescope installed at the Observatoire de Haute-Provence and operated in remote control from Berlin by the Institut fur Planetenforschung, ...DLR, has observed the CoRoT target fields prior to the mission. The resulting archive of stellar photometric light curves is used to search for deep transit events announced during CoRoT's alarm mode to aid in fast photometric confirmation of these events. The 'initial run' field of CoRoT (IRa01) was observed with BEST in 2006 November and December for 12 nights. The first 'long run' field (LRc01) was observed from 2005 June to September for 35 nights. After standard CCD data reduction, aperture photometry has been performed using the ISIS image subtraction method. About 30,000 light curves were obtained in each field. Transits of the first detected planets by the CoRoT mission, CoRoT-1b and CoRoT-2b, were found in archived data of the BEST survey and their light curves are presented here. Such detections provide useful information at the early stage of the organization of follow-up observations of satellite alarm-mode planet candidates. In addition, no period change was found over ~4 years between the first BEST observation and last available transit observations.
In this research, we describe the application of the complexes o-C₆H₄(NSiMe₃)₂ZrCl₂ (1), o-C₆H₄(NSiMe₃)₂TiBr₂ (2), o-C₆H₄(NSiMe₃)₂TiCl₂ (3), C₂H₄(NSiMe₃)₂ZrCl₂ (4), in the ethylene polymerization ...with different Al/M ratios and temperatures. These complexes presented significant catalytic activities in the presence of methyaluminoxane (MAO) as cocatalyst and toluene as solvent, producing high molecular weight linear polyethylenes. Zirconium complexes were more active at 60°C and titanium complexes at 40°C. Zirconium complex (1) showed the best values of activity (347 kg PE/mol Zr h atm) for Al/Zr ratio of 340 and 60°C of temperature. In ethylene-1-hexene copolymerization, the best result was also reached with catalyst 1, at the same conditions.
Kamil crater (Egypt) is a natural laboratory for the study of processes and products associated with the impacts of small iron projectiles on the Earth’s crust. In particular, because of the ...distinctive composition of the impactor (an ungrouped Ni-rich ataxite) and the target (Cretaceous sandstones and minor wackes) it offers a unique opportunity to study impactor–target physical–chemical interactions. Continuing the study of impact melt ejecta, we investigated the mineralogy and geochemistry of 25 Fe-Ni spherules - representative of a suite of 135 - recovered from the soil around the crater. Samples were collected during our 2010 geophysical expedition and investigated by combining scanning electron microscope imaging, electron probe microanalyzer and Raman spectroscopy analyses. Spherules range in size from 100 to 500 µm and show a variety of dendritic textures and mineral compositions dominated by Fe-Ni oxides of the wüstite – bunsenite and magnetite – trevorite series or Fe-Ni metal. All these features indicate quenching of high temperature (1600–1500 °C) oxide or metal liquid droplets under varying oxidizing conditions. A geochemical affinity with the iron impactor recorded by the Fe, Co, Ni ratios in the constituent phases (average Ni/Co element ratio of 25.1 ± 7.6; average Ni/(Ni + Fe) molar ratio of 0.21 ± 0.13), combined with target contamination (i.e., the ubiquitous occurrence of Si and Al from trace to minor amounts), document their origin as impact melt spherules formed through the physical and chemical interaction between metal projectile and silicate target melts and air. We propose a petrogenetic model that envisions formation as liquid droplet residues of immiscible projectile in a mixed silicate melt and their subsequent separation as individual spherules by stripping during hypervelocity ejection. We also argue that this model applies to all impact events produced by small iron projectiles and that such individual Fe-Ni oxide and metal spherules should be common impact products, despite little documentation in the literature. Our detailed mineralogical and geochemical characterization will facilitate their distinction from other, similar spherules of different origin (cosmic spherules, ablation spherules) often encountered in the geologic record.
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