A theoretical model for subnanosecond evolution of a nonequilibrium, inhomogeneous free-electron gas in a laser filament or microfilament wake channel is presented. The spatial distributions of electron density and temperature calculated in axially symmetric geometry as a function of time reveal dynamics on the picosecond time scale that is principally driven by a combination of thermal conduct...

Bright betatron x-ray has been generated using an Ar clustering gas jet target irradiated with a 3 TW ultra-high contrast laser. The measured emission flux with photon energy > 2.4 keV reaches 2×10 8 photons/shot. It is ten-fold enhancement comparing to the emission flux produced by using gas target in the same laser parameters. Observation shows that much larger electron beam charge and diverg...

The screening of a He+ ion embedded in a paramagnetic electron gas is studied using density functional theory within the local spin density approximation. We calculate the induced electron density and the induced density of states for each spin orientation, parallel and antiparallel to that of the electron bound to the He+ ion. Our results show that the screening is preferably due to parallel s...

We measure the energy distribution of electrons passing through a two-dimensional electron gas using a scanning probe microscope. We present direct spatial images of coherent electron wave flow from a quantum point contact formed in a GaAs/AlGaAs two-dimensional electron gas using a liquid He cooled SPM. A negative voltage is placed on the tip, which creates a small region of depleted electrons...

The electron capture gas liquid chromatography test method for chick edema factor has been modified by replacing the alumina column s t ep with an additional sulfuric acid cleanup and a caustic wash which permits a reduction in sample cleanup time. Samples are subjected to double preliminary sulfuric acid cleanup and caustic wash and extracted each time with t r imethyl pentane. The final extra...

in this research, the effect of catalyst type on the cnts synthesis was investigated. the carbonnanotubes (cnts) were produced on stainless steel substrates and two of catalyst with differentcharacteristics by using thermal chemical vapor deposition (tcvd) method. the catalysts have theimportant role for the growth carbon nanotubes (cnts). acetylene gas (c2h2) diluted by nh3 wasused as the reac...

6 Acknowledgments 8 A recent description of an exact map for the equilibrium structure and thermodynamics of a quantum system onto a corresponding classical system is summarized. Approximate implementations are constructed by pinning exact limits (ideal gas, weak coupling), and illustrated by calculation of pair correlations for the uniform electron gas and shell structure for harmonically conf...