Coherent forward scattering of starlight by a cloud of atomic hydrogen

OPTICS COMMUNICATIONS

卷:285

Article

Zagury, Frederic¹  Pellat-Finet, Pierre² 

[1] Harvard Univ, Cambridge, MA 02138 USA

[2] Univ Bretagne S, UMR CNRS 6205, LMBA, F-56321 Lorient, France

关键词: Coherent scattering;    Rayleigh scattering;    Forward scattering;    Atomic hydrogen scattering;    Fresnel zone;    Huygens-Fresnel construction;   

DOI  :  10.1016/j.optcom.2012.06.009

来源: Elsevier

【 摘 要 】

Theory predicts that a plane wave scattered by a thin slab of gas yields, in the forward direction and under specific circumstances, a larger irradiance than would be observed in the absence of the gas. This enhanced Rayleigh scattering depends on the size of the Fresnel zones at the slab location, as seen from the observer's position, and results from the coherence of the scattering. On astronomical scales the exceptional size of Fresnel zones (phi similar to 1500 km) has particular relevance when considering forward-scattered starlight by an interstellar cloud of atomic hydrogen. (C) 2012 Elsevier B.V. All rights reserved.

【 授权许可】

Free