Interaction of slow electrons with surfaces
Slow electrons interaction with periodic and nonperiodic solid surfaces, investigating elastic scattering
Bauer, E.↗
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Cosmic neutrinos
Cosmic neutrinos detection, using inverse beta decay and elastic scattering by electrons to overcome solar neutrino problem
Reines, F.↗
Stabilization method of calculating resonance energies - Model problem
Resonance energies of elastic scattering from one dimensional model potential containing barrier, using stabilization method
Hazi, A. U.↗
Some properties of unstable particle gases
Elastic scattering formation and decay of unstable particle gases, discussing density and corrections to chemical and nuclear statistical equilibrium equations
Delano, M. D.↗
Departures from Jeans' escape for H and He in the earth's atmosphere
Jeans escape rate error for atmospheric H and He attributed to perturbed velocity distribution function, using realistic atom-atom elastic scattering cross sections
Brinkmann, R. T.↗
A comparison of DWBA and coupled channels in the 2s-1d shell
DWBA optical model coupled channels comparison in 2s-1d shell for predicting proton scattering elastic cross sections
Ascuitto, R. J.↗
The response of a 300 micron silicon detector to monoenergetic neutrons determined by the use of the Monte Carlo technique
The response of a 300 micron thick silicon detector to an incident monoenergetic neutron beam is evaluated by the Monte Carlo method for the cases of both a shielded and a bare detector. The result of Monte Carlo calculation, using elastic, inelastic, and absorption reactions indicates that the response of the silicon detector to neutrons is basically due to the elastic scattering. In addition, the gamma rays generated in the shield of the detector will result in a response which is 3 or 4 orders of magnitude smaller than response to incident photons. The response of a bare silicon detector is calculated for neutron energies up to 6 MeV and bias energies from 50 to 250 KeV. It is found that the maximum response for a 300 micron thick silicon detector is less than .004 c/n within this selected neutron and bias energy range. When the pulse height defect is introduced in the calculation the results at low energy neutrons were reduced.
Tahezadeh, M.↗
Use of the Glauber approximation in atomic collisions - A progress report.
Recent progress in the use of the Glauber (1970) theory for estimating atomic collision cross sections is reviewed. It appears that the Glauber approximation is reliable for electron-hydrogen elastic scattering and excitation at incident energies exceeding 30 eV. For more complicated atomic collisions, the usefulness of the Glauber approximation has not yet been significantly tested.
Gerjuoy, E.↗
Free-free absorption of infrared radiation in collisions of electrons with neutral rare-gas atoms
A relationship between the inverse bremsstrahlung absorption cross section and the electron neutral momentum transfer cross section has been utilized to determine the infrared free-free continuum absorption coefficient for the negative ions of helium, neon, argon, krypton, and xenon. The values of the momentum transfer cross section for this calculation have been obtained from experimental measurements. Analytical expressions for the absorption coefficient have also been developed. From the results of this calculation, it is possible to determine the absorption coefficient per unit electron density per neutral atom for temperatures in the range from 2500 to 25,000 K. The results are compared with those from tabulations of previous calculations and those computed from theoretical values of the phase shifts for the elastic scattering of electrons by neutral atoms.
Stallcop, J. R.↗
Annihilation during positron-hydrogen collisions
Using the precision s- and p-wave elastic-scattering wave functions obtained previously, we have calculated the annihilation rate for positrons colliding with hydrogen atoms below the positronium-formation threshold. The s-wave results agree well with those of Humberston, while the p-wave results, which are new, contribute about 20% of the total at the higher energies.
Bhatia, A. K.↗
Standard methods for analysis and interpretation of Lidar data for environmental monitoring
Lidar is similar in principle to microwave radar but uses a pulsed laser as the source and an optical telescope as the receiver. Lidar observations of elastic scattering from aerosols and more recently Raman scattering from molecules have been performed in the atmosphere with favorable results. A description of the Lidar technique is provided. Lidar measurements of remote visibility are discussed together with the measurement of remote visibility and the determination of molecular concentrations.
Melfi, S. H.↗
Glauber exchange amplitudes
The extrapolation method of Ochkur, valid for intermediate energies (about 50 eV), is applied to the exchange form of the Glauber amplitudes. In the case of elastic scattering of electrons from hydrogen atoms at 54.4 Ev the 'post' and 'prior' forms of the exchange amplitude are equivalent, whereas for the case of inelastic scattering there is a minute discrepancy between the two forms of the amplitude. The results are compared with the close-coupling calculation. The investigation is expected to be useful for optically forbidden exchange-allowed transitions due to electron impact at intermediate energies.
Madan, R. N.↗
Phenomenological treatments of cross-sections for proton and hydrogen impact below 1 keV on molecular nitrogen
An analytic independent-particle model is used to construct static potentials to describe the interaction of hydrogen-like ions with atoms and molecules. Parameters of the ion-atom potential are determined from ab initio total energy minimization procedure. The elastic scattering of He(+) from Ne and Ar is investigated as a test case and comparison is made with experiment. The model is then used in conjunction with low energy H(+)-N2 experimental data to construct differential and total cross-sections for the scattering of protons and hydrogen in the energy range of 10 eV to 1 keV from molecular nitrogen. Analytic forms are used to parametrize these cross-sections to facilitate their use in the calculation of energy deposition by protons and hydrogen atoms in atmospheric gases.
Porter, H. S.↗
Electron impact excitation of zinc vapor at 40 eV
The first set of normalized differential and integral cross sections for elastic scattering and excitation involving the four lowest states of zinc is presented, taking into account tests in which the impact energy was 40 eV. In the tests an electron beam was scattered by a zinc target beam. The zinc beam was produced by heating a tantalum crucible containing zinc. An electron-bombardment method was used in heating the crucible.
Williams, W.↗
Stopping cross sections for 0.25-3.0-MeV He-4 ions in cadmium sulfide
Stopping cross sections of He-4 ions with energies between 0.25 and 3.0 MeV have been measured for cadmium sulfide with a probable error of plus or minus 7% to 8%. The experimental method utilized the Rutherford backscattering technique and measured the energy loss of elastically scattered He-4 ions from films of cadmium sulfide sputtered on carbon substrates. The experimental data are compared with recent experimental and theoretical results.
Miller, W. E.↗
Analytic determinations of single-folding optical potentials
A simple analytic method for calculating nucleon-nucleus optical potentials using a single folding of a Gaussian two body interaction with an arbitrary nuclear distribution is presented. When applied to proton-lead elastic scattering, the predicted real part of the Woods-Saxon potential is in substantial agreement with the experimentally determined phenomenological potential, although there are no adjustable parameters. In addition, the volume integrals of both real potentials are nearly identical.
Townsend, L. W.↗
Heating of the interstellar medium by the solar wind
The heating of inflowing interstellar gas by the solar wind is calculated. The experimental differential cross sections have been used for calculating electron-H(He) and proton-H(He) elastic scattering rate coefficients. The solar wind is assumed to be a two-component (protons and electrons), steady, spherically symmetric stream moving radially outward, with the inflowing gas following Keplerian trajectories. The spatial distributions of effective temperature increase within interplanetary space have been obtained.
Kunc, J. A.↗
Optimal filtration of the atmospheric parameters profiles
The idea of optimal Marcovian filtration of fluctuating profiles from lidar signals is developed but as applied to a double-frequency sounding which allows the use of large cross sections of elastic scattering and correct separation of the contributions due to aerosol and Rayleigh scatterings from the total lidar return. The filtration efficiency is shown under different conditions of sounding using a computer model. The accuracy of restituted profiles (temperature, pressure, density) is determined by the elements of a posteriori matrix K. The results obtained allow the determination of the lidar power required for providing the necessary accuracy of restitution of the atmospheric parameter profiles at chosen wavelengths of sounding in the ultraviolet and visible range.
Zuev, V. E.↗