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Laser absorption spectroscopy
Vyhlídka, Štěpán ; Plašil, Radek (advisor) ; Hrubý, Vojtěch (referee)
Study of recombination of molecular ionts in cold plasma plays a key role in our understanding of chemical kinetics in interstellar space or in upper layers of planetar atmospheres. Various metods are used for its study of which important part is laser absorption spectroscopy. Concentration or temperature of measured ionts can be found from their absorption spectra. In the presented work two spectroscopic techniques are briefly introduced - Cavity ringdown spectroscopy and Laser induced reaction technique. Main me- chanisms for spectral linewidth broadening are described and from absorption spectra of H+ 3 and N+ 2 ionts measured by above-mentioned techniques their kine- tic temperature is discovered. Because it is affected by spectral width of applied laser diodes, a part of this work also deals with description of its measurement by self-heterodyne method or Fabry-Pérot interferometer. The spectral width is found for infrared diode DFB laser. 1
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Recombination of ions in plasma at 50-300 K
Rubovič, Peter ; Glosík, Juraj (advisor) ; Fárník, Michal (referee) ; Korolov, Ihor (referee)
A B S T R A C T Title: Recombination of Ions in Plasma at 50 − 300 K Author: Peter Rubovič Supervisor: Prof. RNDr. Juraj Glosík, DrSc. Abstract: Main part of this doctoral thesis lies in a study of recom- bination of atomic and molecular ions in low temperature plasmatic environment with emphasis on effect of third bodies. Stationary After- glow equipped with Cavity Ring Down Spectrometer and Cryogenic Flowing Afterglow with Langmuir Probe II were used to obtain recom- bination rate coefficients. Electron assisted collisional radiative recom- bination of Ar+ ion was studied in the temperature range of 50−100 K and helium assisted collisional radiative recombination was observed too. Both H+ 3 and its isotopologue D+ 3 were studies in flowing after- glow and spectroscopically in stationary afterglow as well. Binary re- combination rate coefficients and ternary recombination rate coeffi- cients for helium assisted ternary recombination were determined in the temperature range of 50 − 250 K. These coefficients were deter- mined also for pure ortho- and para- nuclear spin configurations of H+ 3 in the temperature range of 80 − 200 K. Keywords: dissociative recombination, collisional radiative recombi- nation, H+ 3 , D+ 3 , Ar+ viii
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Recombination of ions in plasma at 50-300 K
Rubovič, Peter
A B S T R A C T Title: Recombination of Ions in Plasma at 50 − 300 K Author: Peter Rubovič Supervisor: Prof. RNDr. Juraj Glosík, DrSc. Abstract: Main part of this doctoral thesis lies in a study of recom- bination of atomic and molecular ions in low temperature plasmatic environment with emphasis on effect of third bodies. Stationary After- glow equipped with Cavity Ring Down Spectrometer and Cryogenic Flowing Afterglow with Langmuir Probe II were used to obtain recom- bination rate coefficients. Electron assisted collisional radiative recom- bination of Ar+ ion was studied in the temperature range of 50−100 K and helium assisted collisional radiative recombination was observed too. Both H+ 3 and its isotopologue D+ 3 were studies in flowing after- glow and spectroscopically in stationary afterglow as well. Binary re- combination rate coefficients and ternary recombination rate coeffi- cients for helium assisted ternary recombination were determined in the temperature range of 50 − 250 K. These coefficients were deter- mined also for pure ortho- and para- nuclear spin configurations of H+ 3 in the temperature range of 80 − 200 K. Keywords: dissociative recombination, collisional radiative recombi- nation, H+ 3 , D+ 3 , Ar+ viii
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Electron Ion Recombination in Low Temperature Plasma
Dohnal, Petr ; Glosík, Juraj (advisor)
The presented work focuses on study of electron - positive ion recombination in low temperature plasma. The principal method used were Flowing afterglow with Langmuir probe and Stationary afterglow with Cavity Ring-Down Spectrometer. For the first time electron and neutral assisted collisional radiative recombination of Ar+ ions was studied in temperature range of 50 - 200 K. Resulting ternary recombination rate coefficients are in good agreement with theoretical predictions. Recombination of H3 + and D3 + ions with electrons was studied in the temperature range of 50 - 300 K and binary and ternary recombination rate coefficients were obtained. The effect of nuclear spin on recombination of H3 + ions with electrons was studied in the temperature range of 80 - 200 K and state selective recombination rate coefficients were obtained for ortho- and para-H3 + . Results show that at 80 K para-H3 + recombines with electrons substantially faster than ortho-H3 + .
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Electron Ion Recombination in Low Temperature Plasma
Dohnal, Petr ; Glosík, Juraj (advisor)
The presented work focuses on study of electron - positive ion recombination in low temperature plasma. The principal method used were Flowing afterglow with Langmuir probe and Stationary afterglow with Cavity Ring-Down Spectrometer. For the first time electron and neutral assisted collisional radiative recombination of Ar+ ions was studied in temperature range of 50 - 200 K. Resulting ternary recombination rate coefficients are in good agreement with theoretical predictions. Recombination of H3 + and D3 + ions with electrons was studied in the temperature range of 50 - 300 K and binary and ternary recombination rate coefficients were obtained. The effect of nuclear spin on recombination of H3 + ions with electrons was studied in the temperature range of 80 - 200 K and state selective recombination rate coefficients were obtained for ortho- and para-H3 + . Results show that at 80 K para-H3 + recombines with electrons substantially faster than ortho-H3 + .
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Recombination of molecular ions with electrons at low temperatures
Kálosi, Ábel ; Plašil, Radek (advisor) ; Kudrna, Pavel (referee)
The aim of this work is the experimental study of recombination of molecular ions with electrons at low temperatures (< 300 K). The work gives an overview of the diagnostic methods, modelling of chemical kinetics, and experimental ap- paratuses Cryo-FALP II and SA-CRDS used in the undertaken measurements. Two processes were studied in the course of this work: state-selective binary disso- ciative recombination of H+ 3 ions in para-H+ 3 and ortho-H+ 3 states, and H2-assisted ternary recombination of H+ 3 . The main result of the state-selective dissociative recombination study is that the rate of recombination in the para-H+ 3 state is at least three times higher than in the ortho-H+ 3 state at 60 K. The study of H2- assisted recombination gave a better understanding of ternary processes of H+ 3 ions and removed further discrepancies between results of afterglow experiments.
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Recombination of ions in plasma at 50-300 K
Rubovič, Peter
A B S T R A C T Title: Recombination of Ions in Plasma at 50 − 300 K Author: Peter Rubovič Supervisor: Prof. RNDr. Juraj Glosík, DrSc. Abstract: Main part of this doctoral thesis lies in a study of recom- bination of atomic and molecular ions in low temperature plasmatic environment with emphasis on effect of third bodies. Stationary After- glow equipped with Cavity Ring Down Spectrometer and Cryogenic Flowing Afterglow with Langmuir Probe II were used to obtain recom- bination rate coefficients. Electron assisted collisional radiative recom- bination of Ar+ ion was studied in the temperature range of 50−100 K and helium assisted collisional radiative recombination was observed too. Both H+ 3 and its isotopologue D+ 3 were studies in flowing after- glow and spectroscopically in stationary afterglow as well. Binary re- combination rate coefficients and ternary recombination rate coeffi- cients for helium assisted ternary recombination were determined in the temperature range of 50 − 250 K. These coefficients were deter- mined also for pure ortho- and para- nuclear spin configurations of H+ 3 in the temperature range of 80 − 200 K. Keywords: dissociative recombination, collisional radiative recombi- nation, H+ 3 , D+ 3 , Ar+ viii
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Recombination of ions in plasma at 50-300 K
Rubovič, Peter ; Glosík, Juraj (advisor) ; Fárník, Michal (referee) ; Korolov, Ihor (referee)
A B S T R A C T Title: Recombination of Ions in Plasma at 50 − 300 K Author: Peter Rubovič Supervisor: Prof. RNDr. Juraj Glosík, DrSc. Abstract: Main part of this doctoral thesis lies in a study of recom- bination of atomic and molecular ions in low temperature plasmatic environment with emphasis on effect of third bodies. Stationary After- glow equipped with Cavity Ring Down Spectrometer and Cryogenic Flowing Afterglow with Langmuir Probe II were used to obtain recom- bination rate coefficients. Electron assisted collisional radiative recom- bination of Ar+ ion was studied in the temperature range of 50−100 K and helium assisted collisional radiative recombination was observed too. Both H+ 3 and its isotopologue D+ 3 were studies in flowing after- glow and spectroscopically in stationary afterglow as well. Binary re- combination rate coefficients and ternary recombination rate coeffi- cients for helium assisted ternary recombination were determined in the temperature range of 50 − 250 K. These coefficients were deter- mined also for pure ortho- and para- nuclear spin configurations of H+ 3 in the temperature range of 80 − 200 K. Keywords: dissociative recombination, collisional radiative recombi- nation, H+ 3 , D+ 3 , Ar+ viii
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Electron Ion Recombination in Low Temperature Plasma
Dohnal, Petr ; Glosík, Juraj (advisor) ; Čurík, Roman (referee) ; Novotný, Oldřich (referee)
The presented work focuses on study of electron - positive ion recombination in low temperature plasma. The principal method used were Flowing afterglow with Langmuir probe and Stationary afterglow with Cavity Ring-Down Spectrometer. For the first time electron and neutral assisted collisional radiative recombination of Ar+ ions was studied in temperature range of 50 - 200 K. Resulting ternary recombination rate coefficients are in good agreement with theoretical predictions. Recombination of H3 + and D3 + ions with electrons was studied in the temperature range of 50 - 300 K and binary and ternary recombination rate coefficients were obtained. The effect of nuclear spin on recombination of H3 + ions with electrons was studied in the temperature range of 80 - 200 K and state selective recombination rate coefficients were obtained for ortho- and para-H3 + . Results show that at 80 K para-H3 + recombines with electrons substantially faster than ortho-H3 + .
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Laser absorption spectroscopy
Vyhlídka, Štěpán ; Plašil, Radek (advisor) ; Hrubý, Vojtěch (referee)
Study of recombination of molecular ionts in cold plasma plays a key role in our understanding of chemical kinetics in interstellar space or in upper layers of planetar atmospheres. Various metods are used for its study of which important part is laser absorption spectroscopy. Concentration or temperature of measured ionts can be found from their absorption spectra. In the presented work two spectroscopic techniques are briefly introduced - Cavity ringdown spectroscopy and Laser induced reaction technique. Main me- chanisms for spectral linewidth broadening are described and from absorption spectra of H+ 3 and N+ 2 ionts measured by above-mentioned techniques their kine- tic temperature is discovered. Because it is affected by spectral width of applied laser diodes, a part of this work also deals with description of its measurement by self-heterodyne method or Fabry-Pérot interferometer. The spectral width is found for infrared diode DFB laser. 1
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