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Search for Planets in Hot Jupiter Systems with Multi-Sector TESS Photometry. III. A Study of Ten Systems Enhanced with New Ground-Based Photometry

Maciejewski G., Fernández M., Sota A., Amado P. J., Ohlert J., Bischoff ., Stenglein W., Mugrauer M., Michel K.-U., Golonka J., Blanco Solsona A., Lapeña E., Molins Freire J., de los Ríos Curieses A., Temprano Sicilia J. A.

Acta Astronomica

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2023

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Vol. 73, No. 1

57--86

EN

The loneliness of hot Jupiters supports the high-eccentricity migration as a primary path leading to the formation of systems with those planets stripped of any close-in planetary companions. Here we present the null results of searches for low-mass planets close to hot Jupiters in 10 planetary systems: HAT-P-4, HAT-P-10, HAT-P-12, HAT-P-17, HAT-P-19, HAT-P-32, HAT-P-44, Qatar-6, TrES-4, and WASP-48. We employed multi-sector time-series photometry from the Transiting Exoplanet Survey Satellite enhanced with new ground-based transit light curves to determine the sizes of hypothetical planets that might still avoid being detected. We redetermined transit parameters for the known hot Jupiters using a homogeneous approach. We refuted transit timing variations for HAT-P-12 b, claimed recently in the literature. The transit timing data permitted us to place tighter constraints on third bodies in HAT-P-19 and HAT-P-32 systems detected in Doppler measurements. We also study four multi-periodic pulsating variable stars in the field around HAT-P-17.

2

A Newtonian Model for the WASP-148 Exoplanetary System Enhanced with TESS and Ground-based Photometric Observations

Maciejewski G., Fernández M., Sota A., García Segura A. J.

Acta Astronomica

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2020

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Vol. 70, No. 3

203--217

EN

The WASP-148 planetary system has a rare architecture with a transiting Saturn-mass planet on a tight orbit which is accompanied by a slightly more massive planet on a nearby outer orbit. Using new space-born photometry and ground-based follow-up transit observations and data available in literature, we performed modeling that accounts for gravitational interactions between both planets. Thanks to the new transit timing data for planet b, uncertainties of orbital periods and eccentricities for both planets were reduced relative to previously published values by a factor of 3-4. Variation in transit timing has an amplitude of about 20 min and can be easily followed-up with a 1-m class telescopes from the ground. An approximated transit ephemeris, which accounts for gravitational interactions with an accuracy up to 5 min, is provided. No signature of transits was found for planet c down to the Neptune-size regime. No other transiting companions were found down to a size of about 2.4 Earth radii for interior orbits. We notice, however, that the regime of terrestrial-size planets still remains unexplored in that system.

3

CoRoT-18 b: Analysis of High-Precision Transit Light Curves with Starspot Features

Raetz St., Heras A. M., Gondoin P., Fernández M., Casanova V., Schmidt T. O. B., Maciejewski G.

Acta Astronomica

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2019

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Vol. 69, No. 3

205--226

EN

When a planet occults a spotty area on a stellar surface, the flux increases and a characteristic feature in a light curve - a bump - is observed. Among the planets detected by the CoRoT-mission CoRoT-18 is especially interesting as it exhibited spot crossings that we have analyzed in detail. We used four ground-based observations obtained at a 1.5-m telescope in Spain and the 13 available CoRoT-transits to refine and constrain stellar, planetary and geometrical parameters of the system. We found that the derived physical properties slightly deviate from the previously published values, most likely due to the different treatment of the stellar activity. Following of a spot over several transits enabled us to measure the stellar rotation period and the spin-orbit alignment. Our derived values of Prot=5.19±0.03 d and λ=6±13° are in agreement with the literature values that were obtained with other methods. Although we cannot exclude a very old age for CoRoT-18, our observations support the young star hypothesis and, hence, yield constraints on the time-scale of planet formation and migration.

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Planet-Star Interactions with Precise Transit Timing. I. The Refined Orbital Decay Rate for WASP-12 b and Initial Constraints for HAT-P-23 b, KELT-1 b, KELT-16 b, WASP-33 b and WASP-103 b

Maciejewski G., Fernández M., Aceituno F., Martín-Ruiz S., Ohlert J., Dimitrov D., Szyszka K., von Essen C., Mugrauer M., Bischoff R., Michel K.-U., Mallonn M., Stangret M., Moździerski D.

Acta Astronomica

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2018

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Vol. 68, No. 4

371--401

EN

Theoretical calculations and some indirect observations show that massive exoplanets on tight orbits must decay due to tidal dissipation within their host stars. This orbital evolution could be observationally accessible through precise transit timing over a course of decades. The rate of planetary in-spiraling may not only help us to understand some aspects of evolution of planetary systems, but also can be used as a probe of the stellar internal structure. In this paper we present results of transit timing campaigns organized for a carefully selected sample of the Northern hemisphere hot Jupiter-like planets which were found to be the best candidates for detecting planet-star tidal interactions. Among them, there is the WASP-12 system which is the best candidate for possessing an in-falling giant exoplanet. Our new observations support the scenario of orbital decay of WASP-12 b and allow us to refine its rate. The derived tidal quality parameter of the host star Q'*=(1.82±0.32)×105 is in agreement with theoretical predictions for subgiant stars. For the remaining systems – HAT-P-23, KELT-1, KELT-16, WASP-33, and WASP-103 – our transit timing data reveal no deviations from the constant-period models, hence constraints on the individual rates of orbital decay were placed. The tidal quality parameters of host stars in at least four systems – HAT-P-23, KELT-1, WASP-33, and WASP-103 – were found to be greater than the value reported for WASP-12. This is in line with the finding that those hosts are main sequence stars, for which efficiency of tidal dissipation is predicted to be relatively weak.

5

Mining cartography in Spain

Fernández M., Prado L., Sánchez A. B.

Geoinformatica Polonica

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2017

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T. 16

149--157

EN

One of the most important points in the mining activity is the control of the exploitation carried out up to date in order to guarantee safety and correct rescue actions in the first place, and in relation to the actions of the development of work, relations between underground work with the outside and know how they affect each other, without a doubt the essential tools to carry out these tasks correctly are the plans and maps.

PL

Jednym z najważniejszych zadań w działalności górniczej jest kontrola prowadzonej eksploatacji, przede wszystkim w celu zagwarantowania bezpieczeństwa i właściwego prowadzenia akcji ratunkowych. Istotny element stanowią także działania dotyczące przebiegu eksploatacji oraz związki pomiędzy pracami podziemnymi i powierzchnią oraz ich wzajemne oddziaływanie. Bez wątpienia ważnymi narzędziami do poprawnej realizacji wymienionych zadań są plany i mapy.