相关论文: Spectroscopic study of unique line broadening and …
Water bath calorimetry was used to demonstrate one more peculiar phenomenon associated with a certain class of mixed gas plasmas termed resonant transfer, or RT plasmas. Specifically, He/H2 (10%) (500 mTorr), Ar/H2 (10%) (500 mTorr), and…
Balmer spectra are investigated which are obtained from hydrogen droplets irradiated by ultra-short intense laser pulses. A unified quantum statistical description of bremsstrahlung, the Stark broadening and the van der Waals profile of…
In this paper the selective broadening of the atomic hydrogen lines in pure H2 and Ar/H2 mixtures in a large 'GEC' cell (36 cm length_ 14 cm ID) was mapped as a function of position, H2/Ar ratio, time, power, and pressure. Several…
This thesis is about the designing and constructing a microwave ion source. The ions are generated in a thermal and dense hydrogen plasma by microwave induction. The plasma is generated by using a microwave source with a frequency of 2.45…
A study of the line shapes of hydrogen Balmer series lines in RF generated low pressure H2/He plasmas produced results suggesting a catalytic process between helium and hydrogen species results in the generation of 'hot' (ca. 28 eV) atomic…
Using femtosecond laser pulses at 800 and 400 nm, we characterize the formation of underdense channels in air generated by laser filamentation at the millijoule energy level by means of transverse interferometry. We find that using tight…
The formation of plasma channels with nonuniformity of about +- 3.5% has been demonstrated. The channels had a density of 1.2x10^19 cm-3 with a radius of 15 um and with length >= 2.5 mm. The channels were formed by 0.3 J, 100 ps laser…
In this paper we describe a simple and inexpensive method to generate plasma using a kitchen microwave. The microwave-generated plasma is characterized by spectroscopic analysis and compared with the absorption spectra of a gas discharge…
In this paper, the interaction of a 1064 nm continuum-wave laser with inductively-coupled plasma generated in a fluorescent light bulb has been studied both experimentally and theoretically. The absorption coefficients pertaining to the…
Some essential features of the ion plasma wave in both kinetic and fluid descriptions are presented. The wave develops at wavelengths shorter than the electron Debye radius. Thermal motion of electrons at this scale is such that they…
Differentially rotating flows of unmagnetized, highly conducting plasmas have been created in the Plasma Couette Experiment. Previously, hot-cathodes have been used to control plasma rotation by a stirring technique [C. Collins et al.,…
Studies on finite-size plasma have attracted a lot of attention lately. They can form by ionizing liquid droplets by lasers. The dynamical behavior of such plasma droplets is, therefore, a topic of significant interest. In particular,…
Understanding the formation and long-timescale evolution of atmospheric plasmas produced by ultrashort, long wavelength IR (LWIR) pulses is an important but partially understood problem. Of particular interest are plasmas produced in air…
Selective H-atom line broadening was found to be present throughout the volume (13.5 cm ID x 38 cm length) of RF generated H2O plasmas in a GEC cell. Notably, at low pressures (ca. <0.08 Torr), a significant fraction (ca. 20%) of the atomic…
A study of Helium-Neon laser plasma lines was done using a double grating spectrometer and a He-Ne laser with an emission wavelength of 632.8 nm (15,802 cm$^{-1}$). The absolute wavenumber, measured to within $\sim0.1$ cm$^{-1}$, and…
Branched flow is an interesting phenomenon that can occur in diverse systems. It is usually linear in the sense that the flow does not alter the medium properties. Branched flow of light on thin films was recently discovered. A question of…
We developed an experimental platform for studying magnetic reconnection in an external magnetic field with simultaneous measurements of plasma imaging, flow velocity, and magnetic-field variation. Here, we investigate the stagnation and…
Linearly polarized solitary waves, arising from the interaction of an intense laser pulse with a plasma, are investigated. New localized structures, in the form of exact \Changes{numerical} nonlinear solutions of the one-dimensional…
Langmuir probe techniques have been used to study time and spatially resolved electron densities and electron temperatures in pulse-modulated hydrogen discharges in two different planar microwave reactors (fmicrowave= 2.45 GHz, tpulse= 1…
In recent decades, different types of plasma sources have been used for various types of plasma processing, such as, etching and thin film deposition. The critical parameter for effective plasma processing is high plasma density. One type…