Halo electron velocity distributions have been surveyed during the first full Ulysses southern polar pass from January 1994 through April 1995. The data examined range from approximately 50◦ S heliolatitude to the maximum poleward extent of the Ulysses orbit, approximately 80◦ S, and then back through the solar equator to 35◦ N heliolatitude. During this traversal the radial distance of Ulysses...

When a pulse superposed on a cw background propagates through an erbium-doped fiber amplifier with a negative group velocity, either pulse broadening or pulse compression can be observed. These effects can be explained in terms of two competing mechanisms: gain recovery and pulse spectrum broadening. The distortion of the pulse shape caused by these effects depends on input pulse width, pump po...

The pulse broadening and decay of coherent sound waves propagating in disordered granular media are investigated. We find that the pulse width of these compressional waves is broadened when the disorder is increased by mixing the beads made of different materials. To identify the responsible mechanism for the pulse broadening, we also perform the acoustic attenuation measurement by spectral ana...

We present a theoretical and experimental study of the line shape of resonant four-wave mixing induced by broad-bandwidth laser radiation that revises the theory of Meacher, Smith, Ewart, and Cooper ~MSEC! @Phys. Rev. A 46, 2718 ~1992!#. We adopt the same method as MSEC but correct for an invalid integral used to average over the distribution of atomic velocities. The revised theory predicts a ...

Calculations of self-broadened half-widths and self-induced pressure shifts are made using the complex Robert–Bonamy formalism. The results of calculations using different approximations of the intermolecular potential indicate that this is a strong collision system. The effects of the imaginary components on the half-widths are studied. The temperature, vibrational, and rotational state depend...

Influence of acoustic beam energy walk-off on characteristics of Bragg diffraction of light is studied theoretically and experimentally by the example of a paratellurite single crystal. Two cases of isotropic and anisotropic light scattering are examined. Angular and frequency characteristics of acousto-optic interaction are calculated in wide ranges of Bragg angles and ultrasound frequencies b...

Spectral lines in the optical spectra of atoms, molecules, and other quantum systems are characterized by a range frequencies ω or wavelengths λ=2πc/ω, where c is speed light. Such frequency wavelength called width spectral (linewidth). It influenced many specific factors. Thermal motion molecules results broadening as result Doppler effect (thermal broadening) their collisions (pressure broade...

The sub-surface damage in ground and subsequently annealed alumina/silicon carbide nanocomposite has been studied by analysis of the x-ray diffraction line width as a function of incidence angle. Bragg peak broadening fell as the depth of penetration of the x-ray beam increased. Despite substantial anisotropy in the uniform compressional strain in the surface of the ground material, no signific...

We investigate the polarization dependence of the spectral broadening of femtosecond pulses inside silicon waveguides by using finite-difference time-domain (FDTD) simulations. Our FDTDmodel includes the anisotropic dependency of predominant nonlinear effects in silicon: Kerr effect, two-photon absorption, and Raman effect. In addition, free-carrier absorption and free-carrier dispersion effect...

Master equations for thermal unimolecular reactions and the reverse thermal recombination reactions are solved for a series of model reaction systems and evaluated with respect to broadening factors. It is shown that weak collision center broadening factors F(cent) (wc) can approximately be related to the collision efficiencies β(c) through a relation F(cent) (wc) ≈ max {β(c) (0.14), 0.64(±0.03...