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1

Search for Planets in Hot Jupiter Systems with Multi-Sector TESS Photometry. IV. Null Detections in 12 Systems

Maciejewski G., Sierzputowska J., Golonka J.

Acta Astronomica

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2023

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Vol. 73, No. 2

159--177

EN

We present the results of our search for nearby planetary companions of transiting hot Jupiters in 12 planetary systems: HAT-P-24, HAT-P-39, HAT-P-42, HAT-P-50, KELT-2, KELT-15, KELT-17, WASP-23, WASP-63, WASP-76, WASP-79, and WASP-161. Our analysis was based on multi-sector time-series photometry from the Transiting Exoplanet Survey Satellite and precise transit timing data sets. We detected no additional transiting planets down to the 2-4 Earth radii regime. For ten hot Jupiters, no departure from linear transit ephemerides was observed. Whilst we refute long-term variations of the orbital period for WASP-161 b, which were claimed in the literature, we notice a tentative hint of the orbital period shortening for WASP-79 b. In addition, we spot a short-period transit timing variation for KELT-2A b with the characteristics typical of the so-called exomoon corridor. We conclude, however, that further observations are required to confirm these findings.

2

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.

3

Search for Planets in Hot Jupiter Systems with Multi-Sector TESS Photometry. II. Constraints on Planetary Companions in 12 Systems

Maciejewski G.

Acta Astronomica

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2022

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Vol. 72, No. 1

1--19

EN

Uninterrupted observations from space-borne telescopes provide the photometric precision that is required to detect shallow transits of small planets missed by ground-based surveys. We used data from the Transiting Exoplanet Survey Satellite (TESS) to search for nearby planetary companions in 12 planetary systems with hot Jupiters: HD 2685, Qatar-10, WASP-4, WASP-48, WASP-58, WASP-91, WASP-120, WASP-121, WASP-122, WASP-140, XO-6, and XO-7. We also applied the transit timing method based on homogeneously determined mid-transit times in order to search for non-transiting companions that could gravitationally perturb the already known planets. We found no additional planets in those systems down to the regime of sub-Neptunian globes. This negative result is in line with statistical studies, supporting the high-eccentricity migration as a pathway of the investigated giant planets to the tight orbits observed today.

4

HD 17092 b Revisited

Adamów M., Niedzielski A. T., Wolszczan A., Maciejewski G.

Acta Astronomica

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2022

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Vol. 72, No. 4

257--266

EN

We present previously unpublished precise radial velocity measurements for HD 17092 and updated keplerian parameters of its low-mass companion HD 17092 b.

5

Search for Planets in Hot Jupiter Systems with Multi-Sector TESS Photometry. I. No Companions in Planetary Systems KELT-18, KELT-23, KELT-24, Qatar-8, WASP-62, WASP-100, WASP-119, and WASP-126

Maciejewski G.

Acta Astronomica

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2020

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Vol. 70, No. 3

181--202

EN

Origins of giant planets on tight orbits, so called hot Jupiters, are a long-lasting question in the planetary formation and evolution theory. The answer seems to be hidden in architectures of those systems that remain only partially understood. Using multi-sector time-series photometry from the Transiting Exoplanet Survey Satellite, we searched for additional planets in the KELT-18, KELT-23, KELT-24, Qatar-8, WASP-62, WASP-100, WASP-119, and WASP-126 planetary systems using both the transit technique and transit timing method. Our homogeneous analysis has eliminated the presence of transiting companions down to the terrestrial-size regime in the KELT-23 and WASP-62 systems, and down to mini-Neptunes or Neptunes in the remaining ones. Transit timing analysis has revealed no sign of either long-term trends or periodic perturbations for all the studied hot Jupiters, including the WASP-126 b for which deviations from a Keplerian model were claimed in the literature. The loneliness of the planets of the sample speaks in favor of the high-eccentricity migration mechanism that probably brought them to their tight orbits observed nowadays. As a by-product of our study, the transit light curve parameters were redetermined with a substantial improvement of the precision for six systems. For KELT-24 b, a joint analysis allowed us to place a tighter constraint on its orbital eccentricity.

6

Planet-Star Interactions with Precise Transit Timing. II. The Radial-Velocity Tides and a Tighter Constraint on the Orbital Decay Rate in the WASP-18 System

Maciejewski G., Knutson H. A., Howard A. W., Isaacson H., Fernández-Lajús E., Di Sisto R. P., Migaszewski C.

Acta Astronomica

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2020

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Vol. 70, No. 1

1--18

EN

From its discovery, the WASP-18 system with its massive transiting planet on a tight orbit was identified as a unique laboratory for studies on tidal planet-star interactions. In an analysis of Doppler data, which include five new measurements obtained with the HIRES/Keck-I instrument between 2012 and 2018, we show that the radial velocity signal of the photosphere following the planetary tidal potential can be distilled for the host star. Its amplitude is in agreement with both theoretical predictions of the equilibrium tide approximation and an ellipsoidal modulation observed in an orbital phase curve. Assuming a circular orbit, we refine system parameters using photometric time series from TESS. With a new ground-based photometric observation, we extend the span of transit timing observations to 28 yr in order to probe the rate of the orbital period shortening. Since we found no departure from a constant-period model, we conclude that the modified tidal quality parameter of the host star must be greater than 3.9×106 with 95% confidence. This result is in line with conclusions drawn from studies of the population of hot Jupiters, predicting that the efficiency of tidal dissipation is 1 or 2 orders of magnitude weaker. As the WASP-18 system is one of the prime candidates for detection of orbital decay, further timing observations are expected to push the boundaries of our knowledge on stellar interiors.

7

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.

8

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.

9

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.

10

New Transit Observations for HAT-P-30 b, HAT-P-37 b, TrES-5 b, WASP-28 b, WASP-36 b and WASP-39 b

Maciejewski G., Dimitrov D., Mancini L., Southworth J., Ciceri S., D'Ago G., Bruni I., Raetz St., Nowak G., Ohlert J., Puchalski D., Saral G., Derman E., Petrucci R., Jofre E., Seeliger M., Henning T.

Acta Astronomica

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2016

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Vol. 66, No. 1

55--74

EN

We present new transit light curves for planets in six extrasolar planetary systems. They were acquired with 0.4-2.2 m telescopes located in west Asia, Europe, and South America. When combined with literature data, they allowed us to redetermine system parameters in a homogeneous way. Our results for individual systems are in agreement with values reported in previous studies. We refined transit ephemerides and reduced uncertainties of orbital periods by a factor between 2 and 7. No sign of any variations in transit times was detected for the planets studied.

11

Konsument wobec innowacji produktowych

Maciejewski G.

Logistyka

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2015

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nr 2

953--960, CD2

PL

Artykuł stanowi głos w dyskusji nad postawami konsumentów wobec innowacji produktowych. Analizując wyniki badań na próbie 410 konsumentów aktywnych na rynku dóbr i usług konsumpcyjnych stwierdzono w większości pozytywne postawy respondentów wobec tego zjawiska. Blisko 2/3 badanych przyznaje, że lubi innowacyjne produkty i kojarzy je z postępem, nowością i lepszą jakością. Mimo to, tylko 1/3 badanych zadeklarowała ich nabycie w ciągu ostatnich 6 miesięcy. Zwolenników innowacji produktowych częściej spotkać można wśród kobiet, niż wśród mężczyzn oraz wśród osób młodych (18-24 lat) niż starszych (40 lat i więcej).

EN

The article is a voice in discussion about consumers’ attitudes towards product innovations. The analysis of research results conducted on 410 consumers says, that most of respondents have positive attitude to this phenomenon. Nearly 2/3 of respondents admit, that they like innovative products and associate them with progress, novelty and better quality. Even so, only 1/3 of respondents declare buying them in next 6 months. Followers of products innovations can be more often found among women than men and among young people (18-24 years) than older (40 years and more).

12

Revisiting Parameters for the WASP-1 Planetary System

Maciejewski G., Ohlert J., Dimitrov D., Puchalski D., Nedoroščík J., Vaňko M., Marka C., Baar S., Raetz St., Seeliger M., Neuhäuser R.

Acta Astronomica

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2014

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Vol. 64, No. 1

27--43

EN

We present thirteen new transit light curves for the WASP-1b exoplanet. Observations were acquired with 0.5 m-1.2 m telescopes between 2007 and 2013. Our homogeneous analysis, which also includes the literature data, results in determining precise system parameters. New values are in agreement with those reported in previous studies. Transit times follow a linear ephemeris with no sign of any transit time variations. This finding is in line with the paradigm that Jupiter-like planets on tight orbits are devoid of close planetary companions. Key words: planetary systems - Stars: individual: WASP-1 - Planets and satellites: individual: WASP-1b

13

On the GJ 436 Planetary System

Maciejewski G., Niedzielski A., Nowak G., Pallé E., Tingley B., Errmann R., Neuhäuser R.

Acta Astronomica

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2014

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Vol. 64, No. 4

323--335

EN

The GJ 436 system contains a transiting planet GJ 436 b which is a hot analogue of Neptune on an eccentric orbit. Recently, two additional transiting sub-Earth planets have been postulated in the literature. We observed three transits of GJ 436 b over the course of three years using two-meter class telescopes, each with a photometric precision better than one millimagnitude. We studied system dynamics based on the existence of the additional planets. We redetermined system parameters, which were in agreement with those found in the literature. We refined the orbital period of GJ 436 b and found no evidence of transit timing variations. The orbital motion of the GJ 436 c planet candidate was found to be significantly affected by the planet b with variations in transit times at a level of 20 minutes. As the orbital period of the GJ 436 d planet candidate remains unknown, our numerical experiments rule out orbits in low-order resonances with GJ 436 b. The GJ 436 system with the hot Neptune and additional two Earth-like planets, if confirmed, would be an important laboratory for studies of formation and evolution of planetary systems.

14

Optimization of functionally gradient materials in valve design under cyclic thermal and mechanical loading

Maciejewski G., Mróz Z.

Computer Assisted Methods in Engineering and Science

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2013

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Vol. 20, no. 2

99--112

EN

The robust and simple optimization method of functionally graded material (FGM) for combined cyclic thermal and mechanical loading with application to valve design is proposed. The optimization procedure starts from the homogeneous ceramic material distribution and after thermomechanical analysis of the whole process, the new distribution of material is determined by reducing concentration of the ceramic phase at places of high tensile stresses and by increasing ceramic contents at places of high effective stresses. The optimal distribution of ceramic phase is found through iterations. We have shown the numerical example of the proposed method for optimization of a composite exhaust valve of combustion engine. The example illustrates the optimal density distribution of ceramic phase of Al2O3 within NiAl matrix. In the design study we have used the transient analysis of stress and temperature fields. The proposed method shares merits of standard optimization and topology optimization, it allows for creating one phase of material inside the other. It can be especially useful to problems of structural elements subjected to thermomechanical loading histories.

15

Research of magnetic properties of permanent magnets in the magnetic circuit with air gap

Karbowiak M., Jankowski B., Kapelski D., Przybylski M., Ślusarek B., Maciejewski G.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 5a

28-30

EN

This work presents results of measurements magnetic properties for permanent magnets in magnetic circuit with different value of air gap. Measurements were conducted at room temperature. Results of the measurements were compared with template data defined according to the inductive method using the histeresisgraph produced by the Italian company Laboratorio Elettrofisico.

PL

W artykule przedstawiono wyniki pomiarów właściwości magnetycznych magnesów trwałych. Pomiary zostały przeprowadzone w temperaturze pokojowej z wykorzystaniem hallotronowych czujników indukcji magnetycznej. Zmieniano wartość szczeliny powietrznej obwodu magnetycznego: 1,62; 2,35; 3,08; 25,6 mm. Wyniki pomiarów porównano z wartościami wzorcowymi otrzymanymi w wyniku pomiarów metodą indukcyjną za pomocą histerezografu włoskiej firmy Laboratorio Elettrofisico.

16

Open Clusters in 2MASS Photometry. II. Mass Function and Mass Segregation

Bukowiecki Ł., Maciejewski G., Konorski P., Niedzielski A.

Acta Astronomica

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2012

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Vol. 62, No. 3

281--296

EN

This is a continuation of our study of open clusters based on the 2-Micron All Sky Survey photometry. Here we present the results of the mass function analysis for 599 known open clusters in the Milky Way. The main goal of this project is a study of the dynamical state of open clusters, the mass segregation effect and an estimate of the total mass and the number of cluster members. We noticed that the cluster size (core and overall radii) decreases along dynamical evolution of clusters. The cluster cores evolve faster than the halo regions and contain proportionally less low-mass stars from the beginning of the cluster dynamical evolution. We also noticed, that the star density decreases for the larger clusters. Finally, we found an empirical relation describing the exponential decrease of the mass function slope with the dynamical evolution of clusters.

17

Refining Parameters of the XO-5 Planetary System with High-Precision Transit Photometry

Maciejewski G., Seeliger M., Adam Ch., Raetz St., Neuhäuser R.

Acta Astronomica

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2011

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Vol. 61, No. 1

25--35

EN

Studies of transiting extrasolar planets provide unique opportunity to get to know the internal structure of those worlds. The transiting exoplanet XO-5 b was found to have an anomalously high Safronov number and surface gravity. Our aim was to refine parameters of this intriguing system and search for signs of transit timing variations. We gathered high-precision light curves for two transits of XO-5 b. Assuming three different limb darkening laws, we found the best-fitting model and redetermined parameters of the system, including planet-to-star radius ratio, impact parameter and central time of transits. Error estimates were derived by the prayer bead method and Monte Carlo simulations. Although system's parameters obtained by us were found to agree with previous studies within one sigma, the planet was found to be notable smaller with the radius of 1.03+0.06-0.05 Jupiter radii. Our results confirm the high Safronov number and surface gravity of the planet. With two new mid-transit times, the ephemeris was refined to BJDTDB=(2454485.66842±0.00028)+(4.1877537±0.000017)E. No significant transit timing variation was detected.

18

Open Clusters in 2MASS Photometry. I. Structural and Basic Astrophysical Parameters

Bukowiecki Ł., Maciejewski G., Konorski P., Strobel A.

Acta Astronomica

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2011

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Vol. 61, No. 3

231--246

EN

The main goal of our project is to obtain a complete picture of individual open clusters from homogeneous data and then search for correlations between their astrophysical parameters. The near-infrared JHKS photometric data from the 2-Micron All Sky Survey were used to determine new coordinates of the centers, angular sizes and radial density profiles for 849 open clusters in the Milky Way. Additionally, age, reddening, distance, and linear sizes were also derived for 754 of them. For these open clusters our results are in satisfactory agreement with the literature data. The analyzed sample contains open clusters with ages in the range from 7 Myr to 10 Gyr. The majority of these clusters are located up to 3 kpc from the Sun, less than 0.4 kpc from the Galactic plane and 6-12 kpc from the Galactic center. The majority of clusters have core radii of about 1.5 pc and the limiting radii of the order of 10 pc. We notice that in the near-infrared, open clusters seem to be greater than in optical bands. We notice that a paucity of clusters is observed at galactic longitudes range from 140° to 200° which probably reflects the real spatial distribution of open clusters in the Galaxy. The lack of clusters was also found in earlier studies.

19

Photometric Studies of Open Clusters: Be 95, Cze 21, Cze 38, Ju 11, King 17, and King 18

Maciejewski G.

Acta Astronomica

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2008

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Vol. 58, No. 4

389--404

EN

Results of investigations of six poorly studied or unstudied open clusters are presented. The ages, interstellar reddenings, distances, and structural parameters were derived based on BV photometry combined with the near-infrared JHKS data. The mass functions were analyzed for four objects and total masses, number of members, and dynamical-evolution parameters were estimated. Berkeley 95 was found to be an extremely young stellar cluster. King 17 and King 18 turned out to be an intermediate-age objects. Czernik 21, Czernik 38, and Juchert 11 were found to be old stellar ensembles of the age of about 1 Gyr old or older. Czernik 38 is located in the Sagittarius Arm while the remaining clusters belong to the Perseus Arm.

20

Elastic micro-strain energy at the austenite-twinned martensite interface

Maciejewski G., Stupkiewicz S., Petryk H.

Archives of Mechanics

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2005

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Vol. 57, nr 4

277-297

EN

A micromechanical scheme is developed for the analysis of elastic micro-strains induced by local incompatibilities at the austenite-twinned martensite interface. The aim of the paper is to estimate the elastic micro-strain energy which is an important factor in the formation of microstructures during the martensitic transformation. The finite deformation framework is applied, consistent with the crystallographic theory of martensite, and full account is taken for elastic anisotropy of the phases. As an example, the microstructures in the cubic-to-orthorhombic transformation in CuAINi shape memory alloy are analyzed by the finite element method for the assumed class of zigzag shapes of the austenite-martensite interface at the micro-level. Finally, the effect of the interphase boundary energy on the microstructure of the transition layer is studied.