Polarization vertical scattering-angle

Here I0 is the intensity of the x-ray beam, r0 = e2/mc2 is the classical electron radius (2.82 x 10 15 m)., P(9,) is the polarization of the x-rays it depends on the angle between the polarization and the scattering vector. For horizontally polarized x-rays, it takes the form P(0, < >) = 1 - sin220 sin2t)>, where 20 is the scattering angle and < > the azimuthal angle with respect to the vertical direction. The formfactor ) is the Fourier transform of the atomic electron density ... 

Figure 7. Polarization pattern, given as a polar plot of the HRS intensity as a function of the angle of polarization of the fundamental wave, for an aqueous suspension of 20 nm diameter gold, (a) Vertically polarized SH scattered light and (b) horizontally polarized SH scattered light (Reprinted from 44 with permission from the American Physical Society)...

In order to eliminate the loss in the scattering cross-section (by cos 20) that arises when the electric field is polarized in the plane of the scattered x-rays, a vertical scattering geometry is often employed. A four-circle diffractometer is generally employed in order to allow access to all points in reciprocal space. Figure 39 shows a schematic drawing, and the various angles [Pg.320]

The polarization factor, Pol, takes into account the variation in scattering intensity caused by the beam polarization, as can be anticipated because elastic scattering is forbidden along the polarization direction of the incident beam. Synchrotron sources typically produce X-ray beams that are linearly polarized in the horizontal plane. Most synchrotron-based scattering measurements are performed with the scattering angle measured in the vertical plane, so that P= 1. For horizontal scattering spectrometers with a horizontally-polarized beam, the polarization factor is P = cos(2 ). A number of spectrometers scan the detector in both the vertical and horizontal planes. 

As discussed in section, R J q,c) and R (q,c) are expressed in terms of R.Jq,c), / ,( , ), andR Jq,c) by Equations 8.2 and 8.3, respectively, with R (0,c)=0. The vertical and horizontal components of light scattered with vertically polarized light from a dilute solution extrapolated to zero scattering angle, Ry (0,c) and R (0,c), respectively, for a monodisperse solute with identical anisotropic scattering elements are given by [13, 28, 84-86] ... 

Low Angle Laser Light Scattering Photometry. Weight-average molecular weights were determined with a KMX-6 photometer (LDC/Milton Roy). The light source was a 2 mW vertically polarized helium-neon laser (A =... 

---