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Kraków, Poland

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. Source


The paper presents research findings on the stay and scientific work of Pierre Berniard in Poland. This French chemist lived in Poland for about twenty years in the late eighteenth century. He was hired as a scientist by the rich aristocratic Wielopolski family from Pińczów. The authors analysed his publications and unpublished correspondence with Jean Hermann, a scholar and the founder of Cabinet of Natural History in Strasbourg. They have identified a large network of Berniard's scientific correspondents and his contribution to geology. The existence of a written account of his stay in Poland, now lost, was raised by his letters to Hermann. Source


Mendys A.,Jagiellonian University | Dzierzega K.,Jagiellonian University | Grabiec M.,Jagiellonian University | Pellerin S.,University of Orleans | 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. Source


Mendys A.,Jagiellonian University | Kanski M.,Jagiellonian University | Farah-Sougueh A.,Jagiellonian University | Farah-Sougueh A.,University of Orleans | 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. Source


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. Source

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