Speckle Noise and Dynamic Range in Coronagraphic Images
Speckle Noise and Dynamic Range in Coronagraphic Images
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冠状图像中的散斑噪声和动态范围
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
L. Jolissaint
中科院分区：
文献类型：
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作者：
R. Soummer;A. Ferrari;C. Aime;L. Jolissaint
本文关注的是在系外行星搜索的背景下，高对比度日冕照相图像的理论特性。本文推导并分析了日冕照相图像中剩余星光的统计特性，描述了日冕照相对散斑和光子噪声的影响。目前对日冕仪的观察表明，高对比度成像的主要限制是由于残留的准静态散斑。我们在本文中解决这个问题，并提出了一个概括我们的统计模型，包括静态，准静态和快速残留大气散斑的描述。结果提供了深入了解波前控制，coronagraphy，主动散斑减少，差分散斑校准的动态范围的影响。这项研究的重点是地面成像与极端自适应光学，但该方法是通用的，足以适用于空间，不同的参数。
This paper is concerned with the theoretical properties of high-contrast coronagraphic images in the context of exoplanet searches. We derive and analyze the statistical properties of the residual starlight in coronagraphic images and describe the effect of a coronagraph on the speckle and photon noise. Current observations with coronagraphic instruments have shown that the main limitations to high-contrast imaging are due to residual quasi-static speckles. We tackle this problem in this paper and propose a generalization of our statistical model to include the description of static, quasi-static, and fast residual atmospheric speckles. The results provide insight into the effects on the dynamic range of wave front control, coronagraphy, active speckle reduction, and differential speckle calibration. The study is focused on ground-based imaging with extreme adaptive optics, but the approach is general enough to be applicable to space, with different parameters.