Publications by authors named "Trifonov T"

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.

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Surveys have shown that super-Earth and Neptune-mass exoplanets are more frequent than gas giants around low-mass stars, as predicted by the core accretion theory of planet formation. We report the discovery of a giant planet around the very-low-mass star GJ 3512, as determined by optical and near-infrared radial-velocity observations. The planet has a minimum mass of 0.

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The crystal structure of naturally occurring zaccariniite (RhNiAs) has been studied in Transmission Electron Microscopy (TEM) with variable angle Precession Electron Diffraction (PED) techniques. The analysis of the data has yielded tetragonal cell parameters of 3.86, 3.

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Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer.

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The reorganization through high-temperature annealing of closely-packed pore arrays can be exploited to create ultra-thin (<20 µm) monocrystalline silicon layers that can work as cheap and flexible substrates for both the electronic and the photovoltaic industries. By introducing a periodic diameter modulation along deep etched pores, many thin layers can be produced from a single substrate and in a single technological process. Besides the periodicity, the exact shape of the modulation also has a profound impact on the process and subtle profile changes can lead to important differences on the process outcome.

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In this Letter we report on the thermal properties of macroporous silicon photonic crystals with the unit cell gradually varied along the pore axis. We show experimentally that arbitrarily large omnidirectional total-reflectance bands can be produced with such structures. We also demonstrate that those bands can be effectively used to reduce thermal radiation in large spectral bands.

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We address the need to develop efficient algorithms for numerical simulation of models, based in part or entirely on adaptive resonance theory. We introduce modifications that speed up the computation of the gated dipole field (GDF) in the Exact ART neural network. The speed increase of our solution amounts to at least an order of magnitude for fields with more than 100 gated dipoles.

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A total of 2400 incomplete helminthological postmortem examinations were carried out with sheep in 1972-1976. Four species of helminths were found in the liver: D. lanceatum (80.

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A total of 55726 Ixodes ticks were collected from farm and wild animals on the territory of Bourgas district in the 1958-1964 period and were specifically differentiated. At a later study in the region of the town of Michourin other 26722 ticks were collected from sheep. A total of 15 species were determined.

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