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We investigate 1D exoplanetary distributions using a novel analysis algorithm based on the continuous wavelet transform. The analysis pipeline includes an estimation of the wavelet transform of the probability density function (p.d.f.) without pre-binning, use of optimized wavelets, a rigorous significance testing of the patterns revealed in the p.d.f., and an optimized minimum-noise reconstruction of the p.d.f. via matching pursuit iterations.In the distribution of orbital periods, \(P\), our analysis revealed a narrow subfamily of exoplanets within the broad family of “warm Jupiters”, or massive giants with \(P\gtrsim 300~\mbox{d}\), which are often deemed to be related with the iceline accumulation in a protoplanetary disk. We detected a p.d.f. pattern that represents an upturn followed by an overshooting peak spanning \(P\sim 300\mbox{--}600~\mbox{d}\), right beyond the “period valley”. It is separated from the other planets by p.d.f. concavities from both sides. It has at least 2-sigma significance.In the distribution of planet radii, \(R\), and using the California Kepler Survey sample properly cleaned, we confirm the hints of a bimodality with two peaks about \(R=1.3R_{\oplus }\) and \(R=2.4R_{ \oplus }\), and the “evaporation valley” between them. However, we obtain just a modest significance for this pattern, 2-sigma only at the best. Besides, our follow-up application of the Hartigan and Hartigan dip test for unimodality returns 3 per cent false alarm probability (merely 2.2-sigma significance), contrary to 0.14 per cent (or 3.2-sigma), as claimed by Fulton et al. (2017). 相似文献
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Astronomy Reports - The results of many-year infrared observations of the Herbig AeBe star AB Aur at 1-5 μm (JHKLM bands) are presented. The duration of the photometric series, together with... 相似文献
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Geotectonics - The tectonics, morphological features, and development stages of the Belomorian‒Severodvinsk shear zone (northwestern part) found in the East European Platform are considered.... 相似文献
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The structural setting and geochemistry of the Devonian dikes in the Kola Peninsula are considered. The alkaline dikes are
controlled by rift- and drift-related structural elements. The first type of structures is exemplified by the Khibiny-Kontozero
Fault Zone, which is regarded as a propagation zone of the East Barents Rift. The second type comprises Early Precambrian
structural elements reactivated during Devonian drift of the East European Plate. Alkaline dikes occur in the ring structures
at the ends of rifts and in the accommodation zones where the polarity of the main fault plane changes. These are the sites
of accumulation and abrupt relaxation of tectonic stresses. Despite the significant differences in the petrography and chemistry
of alkaline dikes, all of them are enriched in REE, apparently due to the elevated concentrations of these elements in the
fluids. The dolerite dikes at the Murmansk Coast are located in the outer zone of the vast, concentrically zoned plateau basalt
province with the East Barents Trough as its center. According to geophysical data, basaltic flows are suggested within this
trough. The dolerite dikes increase in number in the inland propagation zone of the East Barents Trough extending in the Baltic
Shield. The alkaline igneous rocks of the Kola Peninsula were formed under local compression at the periphery of the plateau
basalt province. 相似文献
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E. N. Terekhov A. S. Baluev T. F. Shcherbakova I. S. Ipat’eva 《Doklady Earth Sciences》2012,442(2):226-234
A structural-geochemical study has been conducted on the dikes of presumably Devonian mafic rocks confined to a small graben
filled in with Riphean sedimentary rocks hosted by Early Precambrian granite-gneiss of the Murmansk block. It has been demonstrated
that the dolerite dikes of this region can be considered as manifestations of trap magmatism whose products fill in the foundation
of the East Barents riftogenic downfold. In turn, manifestations of alkaline and kimberlite rocks of the White Sea region
are confined to the peripheral portion of the trap magnetism area. Zircons from dolerite transecting Late Riphean sediments
examined in two laboratories have a concordant age of 2.74–2.72 Ba, while zircons from a similar dike located in granite-gneiss
of the basement are characterized by an age range of 2700–155 Ma, and the concordant age based on 4 points is 790 Ma. All
these factors indicate that the age determinations of the mafic rocks are ambiguous, particularly in the zone of transition
from the center of the trap province to its periphery, where alkaline magmatism is observed. 相似文献
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Roman V. Baluev 《Celestial Mechanics and Dynamical Astronomy》2011,111(1-2):235-266
We use full available array of radial velocity data, including recently published HARPS and Keck observatory sets, to characterize the orbital configuration of the planetary system orbiting GJ876. First, we propose and describe in detail a fast method to fit perturbed orbital configuration, based on the integration of the sensitivity equations inferred by the equations of the original N-body problem. Further, we find that it is unsatisfactory to treat the available radial velocity data for GJ876 in the traditional white noise model, because the actual noise appears autocorrelated (and demonstrates non-white frequency spectrum). The time scale of this correlation is about a few days, and the contribution of the correlated noise is about 2 m/s (i.e., similar to the level of internal errors in the Keck data). We propose a variation of the maximum-likelihood algorithm to estimate the orbital configuration of the system, taking into account the red noise effects. We show, in particular, that the non-zero orbital eccentricity of the innermost planet d, obtained in previous studies, is likely a result of misinterpreted red noise in the data. In addition to offsets in some orbital parameters, the red noise also makes the fit uncertainties systematically underestimated (while they are treated in the traditional white noise model). Also, we show that the orbital eccentricity of the outermost planet is actually ill-determined, although bounded by ~0.2. Finally, we investigate possible orbital non-coplanarity of the system, and limit the mutual inclination between the planets b and c orbits by 5°?C15°, depending on the angular position of the mutual orbital nodes. 相似文献
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Complex geological and geophysical data obtained during recent research by the Marine Arctic Geological Survey Expedition
OJSC (MAGSE) indicate that the Riphean Chapoma graben located on the southeastern shore of the Kola Peninsula has its extension
under the Gorlo Strait of the White Sea water area and joins the Leshukonsk riftogenous graben as an extended narrow trench
in the crystal foundation of the platform. From this it follows that the Chapoma graben is the central segment of the White
Sea paleorift system. Only the northwestern edge and probably the upper part of the graben section outcrop on the Kola Peninsula,
which represents a highly elevated block of the platform foundation. To emphasize the unity of this paleorift zone, it makes
sense to call it the Chapomo-Leshukonsk Paleorift in contrast to the traditional name Kerets-Leshukonsk. The echelon position of the riftogenous troughs of the Chapomo-Leshukonsk paleorift, the form itself of the Leshukonsk and
Azopolsk troughs being close to pull-apart assumes their occurrence and development under transtension conditions with elements
of the right-side shear along the steep northeastern edges of the grabens. 相似文献