Appendices A and B are only available in electronic form at http://www.aanda.org

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Also associated researcher at CNRS UMR 8112 - LERMA, Observatoire de Paris, Section de Meudon, 92195 Meudon, France.

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... Trujillo Bueno

Consejo Superior de Investigaciones Científicas (Spain).

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... transition)

Figure 2 of Manso Sainz & Landi Degl'Innocenti (2002) shows the variation with wavelength of the anisotropy factor, $w=\sqrt{2}J^2_0/J^0_0$ , and of the number of photons per mode (i.e., $\bar{n}=J^0_0(c^2/2h\nu^3)$ ) of the solar continuum radiation.

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... polarized

Note that there can be no scattering polarization in the H line because its lower and upper levels cannot be aligned.

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