Precision Spectroscopy in Astrophysics
Precision Spectroscopy in Astrophysics
复制标题
天体物理学中的精密光谱学
DOI：
10.1007/978-3-540-75485-5
复制
发表时间：
2008
影响因子：
3.2
通讯作者：
M. Romaniello
中科院分区：
文献类型：
--
作者：
N. Santos;L. Pasquini;A. Correia;M. Romaniello
由于以下三个原因，提取 CCD 探测器记录的中阶梯光栅光谱是一个巨大的挑战：(1) 像素采样通常接近或更差于最佳值，(2) 光谱顺序相对于 CCD 行（或列）是弯曲和倾斜的，(3) 每个像素都包含来自各种来源的额外噪声，如图 1 所示。最佳提取的主要目标是恢复尽可能多的科学信号，同时最大限度地减少噪声的影响。在这里，我们提出了狭缝函数分解算法，该算法用狭缝照明轮廓的重建来代替滑动窗口中的求和。重建被表述为通过迭代解决的逆问题，并且它对于大多数系统问题（包括宇宙射线和外观缺陷）具有鲁棒性。
The extraction of the echelle spectra registered with a CCD detector represents a big challenge because of three reasons:(1) the pixel sampling is often close or worse then optimal,(2) spectral orders are curved and tilted with respect to the CCD rows (or columns) and (3) every pixel contains additional noise coming from various sources as illustrated in Figure 1. The main goal of an optimal extraction is to recover as much of the science signal while minimizing the contribution of the noise. Here we present the Slit Function Decomposition algorithm which replaces the summation in a sliding window with a reconstruction of the slit illumination profile. The reconstruction is formulated as an inverse problem solved by iterations and it is robust against most of the systematic problems including cosmic rays and cosmetic defects.