Results 271 to 280 of about 6,394,824 (315)

Cross-section measurements for electron-impact ionization of atoms

Physical Review A, 1990
Absolute electron-impact cross sections have been measured from 0 to 200 eV for single ionization of 16 atoms (Mg, Fe, Cu, Ag, Al, Si, Ge, Sn, Pb, P, As, Sb, Bi, S, Se, and Te) with an estimated accuracy of \ifmmode\pm\else\textpm\fi{}10%. Combined with our recent measurements of He, Ne, Ar, Kr, Xe, F, Cl, Br, I, Ga, and In [Wetzel et al., Phys. Rev. A
, Freund, , Wetzel, , Shul, , Hayes
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Photoionisation cross section of atomic oxygen

Journal of Physics B: Atomic and Molecular Physics, 1978
The photoionisation cross section for the ground state 2s22p4 3P of O I is calculated in the close-coupling approximation employing the frozen-cores model. Results include detailed resonance analysis using accurate interpolation and extrapolation procedures.
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Cross-sectional atomic force microscopy of semiconductor nanostructures

Journal of Applied Physics, 1995
We performed imaging of semiconductor nanostructures (quantum wells and quantum wires) by atomic force microscopy of the cleaved edge of the samples under ambient conditions. Selective etching was used to enhance the composition contrast of the semiconductor heterostructure layers, and a procedure for retrieving the nanostructure dimensions from the ...
Dwir, B., Reinhardt, F., Kapon, E.
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Cross-sectional atomic force imaging of semiconductor heterostructures

Materials Science and Engineering: B, 1996
Abstract We performed imaging of semiconductor heterostructures, in particular GaAs-AlGaAs quantum wells and quantum wires, by atomic force microscopy (AFM) of the cleaved edge of the samples. We used two methods to transform the alloy composition into height differences, measurable by AFM: natural oxidation and selective etching.
B Dwir, F Reinhardt, G Biasiol, E Kapon
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Electron-impact-ionization cross sections of the Ga and In atoms

Physical Review A, 1989
Absolute electron-impact cross sections for single, double, and triple ionization of gallium and indium have been measured from 0 to 200 eV. Beams of Ga and In atoms are formed by charge-transfer neutralization of 3-keV-ion beams with triethylamine or xenon.
, Shul, , Wetzel, , Freund
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Photoionization cross section and resonance structure of atomic yttrium

Physical Review A, 1987
Many-body perturbation theory has been used to calculate the photoionization cross section of neutral yttrium from threshold at 6.52--100.0 eV. The resonance structure due to 4p excitations to 4d states has also been calculated. Hartree-Fock results are also presented for comparison.
, Wijesundera, , Kelly
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Positron-atom doubly differential ionization cross sections

Physical Review A, 1994
Doubly differential ionization cross sections for positron impact on argon atoms were determined by energy- and angle-resolved measurements of ejected electrons in time correlation with the produced ions. Corresponding measurements with incident electrons were made for comparison.
, Schmitt, , Cerny, , Möller, , Raith, , Weber   +4 more
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Electron-impact-ionization cross section for the hydrogen atom

Physical Review A, 1994
A distorted-wave Born exchange approximation was used to calculate the cross section for electron-impact ionization of the hydrogen atoms. Both the integral and energy-differential cross section were calculated. The results were compared with the latest experimental data and other theoretical calculations.
, Hu, , Fang, , Wang, , Yang
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Atom-atom momentum-transfer cross section in the presence of resonances

Physical Review A, 1983
The atom-atom momentum-transfer cross section is analyzed for low-energy collisions in which resonances may be present. It is shown that their contribution to this cross section can be substantial, and this is confirmed in the calculation on ${\mathrm{H}}^{+}$-He system.
S. Bosanac, K. Knešaurek
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Measurement of Differential Atomic Collision Cross Sections

Review of Scientific Instruments, 1971
An apparatus for the study of differential angular scattering of atomic projectiles by gas targets is described. The design facilitates system alignment and provides for accurate reproducible location of components. The performance of the instrument is studied for scattering of H+ at 5–25 keV energies by helium and argon targets.
R. L. Fitzwilson, E. W. Thomas
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