Angular distribution polarized light

Many readers will have some familiarity with the standard expressions for the angular distribution of photofragments ejected from a randomly oriented (gas-phase) molecule by perfectly polarized light ... 

This forward-backward asymmetry of the photoelectron distribution, expected when a randomly oriented sample of molecular enantiomers is ionized by circularly polarized light, is central to our discussion. The photoelectron angular... 

Let us consider a population of N molecules randomly oriented and excited at time 0 by an infinitely short pulse of light polarized along Oz. At time t, the emission transition moments ME of the excited molecules have a certain angular distribution. The orientation of these transition moments is characterized by 0E, the angle with respect to the Oz axis, and by (azimuth), the angle with respect to the Oz axis (Figure 5.5). The final expression of emission anisotropy should be independent of

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The propagation of light in multiple scattering media is quantified usually on the level of radiative transfer or particle diffusion. Scattering, absorption, and emission are considered as independent statistical processes, and the consequences of wave character are either ignored, like polarization, or added as an additional parameter, like the phase function P(ji n) that describes the angular distribution of scattered... 

Equation (5.6) applies to incident unpolarized light it is important to remember that the angular distribution of the scattered light depends on the polarization of the incident light ... 

The angular distribution of the scattered light (normalized to the forward direction) for incident light polarized parallel and perpendicular to the scattering plane and unpolarized is shown in Fig. 5.1 both linear and polar plots are given. 

Figure 13.4 Scattering of unpolarized light by spheres. The top curves show the angular distribution of the scattered light and the bottom curves its degree of polarization. From Hansen and Travis (1974) copyright 1974 by D. Rcidel Publishing Company. Dordrecht. Holland.

Ormerod et al. (780) have studied the photolysis of KI with pulsed polarized light of wavelength 3472 A. From the angular distribution of the product I atoms dissociated from a molecular beam of KI, they have concluded that the recoil I atom direction is nearly perpendicular to the electric vector of the polarized light. The results suggest a transition from the ionic ground state to a neutral excited state. 

The discovery of confinement resonances in the photoelectron angular distribution parameters from encaged atoms may shed light [36] on the origin of anomalously high values of the nondipole asymmetry parameters observed in diatomic molecules [62]. Following [36], consider photoionization of an inner subshell of the atom A in a diatomic molecule AB in the gas phase, i.e., with random orientation of the molecular axis relative to the polarization vector of the radiation. The atom B remains neutral in this process and is arbitrarily located on the sphere with its center at the nucleus of the atom A with radius equal to the interatomic distance in this molecule. To the lowest order, the effect of the atom B on the photoionization parameters can be approximated by the introduction of a spherically symmetric potential that represents the atom B smeared over... 

Auger electrons can also possess an angular distribution (see the discussion in connection with equ. (1.30)). For Auger transitions induced by arbitrary polarized light this angular distribution is parametrized by an expression similar to equ. (1.53) for photoelectrons ... 

This result agrees with the general formulation for completely linearly polarized light (equ. (3.28) with = 1) if the angular distribution parameter )SA is defined as... 

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