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Foster H.M.,Missouri State University | Reed M.D.,Missouri State University | Telting J.H.,Nordic Optical Telescope | Ostensen R.H.,Catholic University of Leuven | Baran A.S.,University Pedagogiczny
Astrophysical Journal | Year: 2015

We analyze 3 yr of nearly continuous Kepler spacecraft short cadence observations of the pulsating subdwarf B (sdB) star KIC 3527751. We detect a total of 251 periodicities, most in the g-mode domain, but some where p-modes occur, confirming that KIC 3527751 is a hybrid pulsator. We apply seismic tools to the periodicities to characterize the properties of KIC 3527751. Techniques to identify modes include asymptotic period spacing relationships, frequency multiplets, and the separation of multiplet splittings. These techniques allow for 189 (75%) of the 251 periods to be associated with pulsation modes. Included in these are three sets of ℓ = 4 multiplets and possibly an ℓ = 9 multiplet. Period spacing sequences indicate ℓ = 1 and 2 overtone spacings of 266.4 0.2 and 153.2 0.2 s, respectively. We also calculate reduced periods, from which we find evidence of trapped pulsations. Such mode trappings can be used to constrain the core/atmosphere transition layers. Interestingly, frequency multiplets in the g-mode region, which sample deep into the star, indicate a rotation period of 42.6 3.4 days while p-mode multiplets, which sample the outer envelope, indicate a rotation period of 15.3 0.7 days. We interpret this as differential rotation in the radial direction with the core rotating more slowly. This is the first example of differential rotation for a sdB star. © 2015. The American Astronomical Society. All rights reserved..


Baran A.S.,University Pedagogiczny | Telting J.H.,Nordic Optical Telescope | Nemeth P.,Catholic University of Leuven | Nemeth P.,University of Bamberg | And 2 more authors.
Astronomy and Astrophysics | Year: 2015

We present our analysis of Kepler data of a pulsating subdwarf B star, KIC? 8302197. We used Q5-17 data and applied a Fourier technique to extract 30 significant pulsation modes. We searched for multiplets and period-spacing sequences to perform a mode identification and to derive a rotation period. To our surprise, KIC? 8302197 does not show any multiplets. We explain the lack of multiplets by either a very slow rotation (longer than ~1000 days) or a unique (pole-on) orientation of the pulsation axis. Our mode identification relied solely on period spacing. We were successful in identifying modal degrees of most of the detected modes. An analysis of the period stability did not show any evidence of a companion to the host star. In addition to photometric data, several spectroscopic observations were collected. Our twelve radial-velocity measurements constrain a possible orbital radial-velocity amplitude to be smaller than about 10 km? s-1. Furthermore, based on color indices we constrained a possible companion to be an M or later type main sequence, a compact or a substellar object. We found that the atmospheric parameters (Teff = 27 450 ± 200 K, log? g = 5.438 ± 0.033 dex, and log? (nHe /nH) = -2.56 ± 0.07 dex) of KIC? 8302197 are consistent with other slow pulsating subdwarf B stars. From the optical spectra we derived C, N, O, Si and Fe abundances, and set an upper limit for the S abundance. © ESO, 2014.


Wieczorek-Ciurowa K.,Cracow University of Technology | Dulian P.,Cracow University of Technology | Bak W.,University Pedagogiczny | Kajtoch C.,University Pedagogiczny
Przemysl Chemiczny | Year: 2011

Elec. properties of CaTiO3 were modified with Cu ions by high-energy ball milling in air. Several solid state solns. of Ca 1-xCuxTiO3 (0 ≤ × ≤ 0.8) and CaTi1-xCuxO3-δ (x = 0.02 and 0.20) were produced. The addn. of Cu resulted in an improvement of dielec. permittivity, dielec. loss and conductivity of the solns. The optimum compn. was CaTi 0,80Cu0,20O3.


Pokrzywka B.,University Pedagogiczny | Mendys A.,Jagiellonian University | Dzierzega K.,Jagiellonian University | Grabiec M.,Jagiellonian University | Pellerin S.,French National Center for Scientific Research
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2012

Shock wave produced by a laser induced spark in argon at atmospheric pressure was examined using Rayleigh and Thomson scattering. The spark was generated by focusing a laser pulse from the second harmonic (λ = 532 nm) of a nanosecond Nd:YAG laser using an 80 mm focal length lens, with a fluence of 2 kJ·cm - 2. Images of the spark emission were recorded for times between 30 ns and 100 μs after the laser pulse in order to characterize its spatial evolution. The position of the shock wave at several instants of its evolution and for several plasma regions was determined from the Rayleigh-scattered light of another nanosecond Nd:YAG laser (532 nm, 40 J·cm - 2 fluence). Simultaneously, Thomson scattering technique was applied to determine the electron density and temperature in the hot plasma core. Attempts were made to describe the temporal evolution of the shock wave within a self-similar model, both by the simple Sedov-Taylor formula as well as its extension deduced by de Izarra. The temporal radial evolution of the shock position is similar to that obtained within theory taking into account the counter pressure of the ambient gas. Density profiles just behind the shock front are in qualitative agreement with those obtained by numerically solving the Euler equations for instantaneous explosion at a point with counter pressure. © 2012 Elsevier B.V.


Baran A.S.,University Pedagogiczny | Koen C.,University of the Western Cape | Pokrzywka B.,University Pedagogiczny
Monthly Notices of the Royal Astronomical Society: Letters | Year: 2015

We present our analysis of simulated data in order to derive a detection threshold which can be used in the pre-whitening process of amplitude spectra. In case of ground-based data of pulsating stars, this threshold is conventionally taken to be four times the mean noise level in an amplitude spectrum. This threshold is questionable when space-based data are analysed. Our effort is aimed at revising this threshold in the case of continuous 90-d Kepler K2 phase observations. Our result clearly shows that a 95 per cent confidence level, common for ground observations, can be reached at 5.4 times the mean noise level and is coverage dependent. In addition, this threshold varies between 4.8 and 5.7, if the number of cadences is changed. This conclusion should secure further pre-whitening and helps to avoid over-interpretation of spectra of pulsating stars observed with the Kepler spacecraft during K2 phase. We compare our results with the standard approach widely used in the literature. © 2014 The Authors.


Mendys A.,Jagiellonian University | Kanski M.,Jagiellonian University | Farah-Sougueh A.,Jagiellonian University | Farah-Sougueh A.,University of Orléans | And 3 more authors.
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2014

A laser Thomson scattering method was applied to investigate the local Saha-Boltzmann equilibrium in aluminum laser-induced plasma. Plasma was created in ambient air using 4.5 ns pulses from a Nd:YAG laser at 532 nm, focused on an Al target. Spatially resolved measurements, performed for the time interval between 600 ns and 3 μs, show electron density and temperature to decrease from 3.4 × 1023 m- 3 to 0.5 × 1023 m- 3 and from 61,000 K to 13,000 K in the plasma core. The existence of local thermodynamic equilibria in the plasma was verified by comparing the rates of the collisional to radiative processes (the McWhirter criterion), as well as relaxation times and diffusion lengths of different plasma species, with the appropriate rate of electron density evolution and its gradients at given, experimentally determined, electron temperatures. We found these criteria to be much easier to satisfy for metallic plasma species than for nitrogen. The criteria are also easier to satisfy in the plasma core of higher electron density. © 2014 Elsevier B.V.


Mendys A.,Jagiellonian University | Dzierzega K.,Jagiellonian University | Grabiec M.,Jagiellonian University | Pellerin S.,University of Orléans | And 3 more authors.
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2011

The Thomson scattering method was applied to quantify the electron number density and temperature of a laser spark formed in argon. The laser spark was generated by focusing a 15 mJ beam from the second harmonic (λ L = 532 nm) of a nanosecond Nd:YAG laser with an 80 mm focal length lens. Images of the spark emission were obtained for times between 1 ns and 20 μs after the laser pulse in order to characterize its spatial evolution. The electron density and temperature for the core of the plasma plume at different instants of its evolution were determined from the Thomson scattered spectra of another nanosecond Nd:YAG laser (532 nm, 10 to 60 mJ/pulse). In the time interval between 400 ns and 10 μs between the laser induced plasma and Thomson scattering probe pulses, we found ne and Te to decrease from 4.3 × 1023 m- 3 to 2.4 × 10 22 m- 3 and from 50 700 K to 11 100 K, respectively. Special care was paid to the plasma disturbance by the probe laser pulse in Thomson scattering experiments due to absorption of laser photons by electrons through the inverse bremsstrahlung process. © 2011 Elsevier B.V. All rights reserved.


Wala A.,Emerytowany Pracownik Bylego Przedsiebiorstwa Geologicznego W Krakowie | Wolska A.,University Pedagogiczny | Jelen P.,Absolwentka Uniwersytetu Jagiellonskiego
Biuletyn - Panstwowego Instytutu Geologicznego | Year: 2015

The paper describes localization and architecture of a uranium-bearing fault, called the Stary Julianów Fault (uStJ). The fault studied occurs in a north-western fragment of the sudetic part of the Góry Sowie Gneiss Massif (MGS ), in the area of the Wałbrzych Foothills, between Stary Julianów and Dziećmorowice. It is one of faults that make up the northern part of a broad dislocation zone extending from Stary Julianów to Zagórze Ślaskie, in which the occurrence of hydrothermal mineralization, called mineralization from Dziećmorowice, was described. Information about the Stary Julianów Fault obtained during its exploration by underground workings to the depth of 345 m and the extension of 900 m, which were made in the years 1949-1952 in connection with uranium ore mining. The Stary Julianów Fault belongs to "older" faults with direction NW -SE and it is oriented crosswise to macrofold which occurs in Julianów region. The architecture of a fault zone of the Stary Julianów Fault consists of two parts: a fault core and a damage zone. The fault core is represented by narrow zone, composed of the fault rocks with the occurrence of uranium-bearing calcite lenses. The damage zone is brittle deformation with instances of carbonate mineralization and hydrothermal alteration of gneisses. It is particularly wide developed in the east side of the Stary Julianów Fault. The architecture and position of the Stary Julianów Fault in the tectonic structure of the region suggests its formation during the Variscan evolution of the Góry Sowie Gneiss Massif.


Dzierzega K.,Jagiellonian University | Mendys A.,Jagiellonian University | Pokrzywka B.,University Pedagogiczny
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2014

This article describes laser Thomson scattering as applied to investigate laser-induced plasmas originating from gas breakdown or ablation of solid samples. Thomson scattering provides a reliable and direct mean of determining plasma electron density and electron temperature with high spatial and temporal resolution. Moreover, unlike e.g. optical emission spectroscopy, no assumptions about axial symmetry, thermodynamic conditions in the plasma or its chemical composition are needed to quantify these fundamental plasma parameters. Because Thomson scattering is inherently accompanied by Rayleigh light scattering, information about concentration of heavy particles and their temperature can be simultaneously derived from the experimental data. The heavy particle temperature and the electron one are the primary indicators of the plasma thermodynamic equilibrium. The goals of this article are to describe the theory of Thomson scattering relevant for the studies of low-temperature laser-induced plasmas, discuss the instrumental details of Thomson scattering experiments, and review the results of studies in which this technique has been used to characterize laser-induced plasmas. © 2014 Elsevier B.V. All rights reserved.


Dormus K.,University Pedagogiczny
Przeglad Geofizyczny | Year: 2013

Maurycy Pius Rudzki was one of the pioneers of geophysics, an academic discipline that came to being towards the end of the 19th century. After completing his science degree at universities in Lviv and Vienna, Rudzki worked at Russian higher education institutions in Kharkiv and Odessa. Afterwards, he came back to his home country and settled in Krakow. On November 1st, 1895, Rudzki took charge of the Chair of Mathematical Geophysics and Meteorology at the Jagiellonian University. It was the first Chair of Geophysics in Europe. In 1902, Rudzki became the director of the Krakow Observatory, where he conducted meteorological, magnetic and gravimetric research. There, Rudzki also set up one of the first seismological stations in Europe. Rudzki wrote numerous prominent works devoted to the physics of Earth. In addition, he authored several distinguished textbooks, including The Physics of Earth, Theoretical Astronomy and The Rules of Meteorology.

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