数据处理和发布-lamost.pdf

2016年度 LAMOST用户培训会 数据处理和发布 LAMOST数据部 国家天文台 2016.7.12 主题 •  LAMOST的数据流 •  巡天观测模式和数据处理和产品 •  DR2国际发布版的修正及参数误差 •  DR4 Alpha Q1 Q2 Q3的统计 •  数据的使用和获取 数据流简介 形成数据产品发布 通过光谱分析进行分类和测量 （从光谱获得物理参数） 观测获得光谱的CCD 图像 （图像处理和物理定标过程） 选择观测目标 （根据科学目标选择光谱采样） et al. 2002), aim to extract spectra from CCD images and calibrate them. The main tasks simplified as follows. of the 2D pipeline include the steps of fiber tracing, flux extraction, wavelength calibration, F (j, ) = [F (j, ) ⇥ d () + sky ()] ⇥ d () ⇥ d () + scatter(j, ) + C (j, ) + B (1) flat fielding, sky subtraction, flux calibration, multi-exposure co–addition and connection o i s r f p k 数据处理过程 of the two wavelength bands. Since the data reduction steps are reverse process of data In this equation, F (j, ) is the observed signal, where j denotes the j –th fiber and o acqusition, we should understand the data acquisition process of LAMOST, which could be – 5 – denotes the wavelength; •  2D pipeline simplified as follows. sky () is sky background; – 5 – r F (j, ) is the target signal before penetrating through atmosphere without extinction; i F (j, ) = [F (j, ) ⇥ d () + sky ()] ⇥ d () ⇥ d () + scatter(j, ) + C (j, ) + B (1) o i s r