标题： GaiaNIR：关于处理和测光的说明 显示英文标题

标题： GaiaNIR: Note on processing and photometry

摘要： 一些关于天体测量卫星上的处理和测光的想法被提出，特别是为GaiaNIR设计的，GaiaNIR可能在2045年左右发射，作为Gaia的后续任务。 - 如果实施了从探测器数据中提出的初始处理，GaiaNIR的灵敏度将提高，图像重叠减少，PSF校准更简单，因为扫描方向上的模糊将变得不显著。 - 为了满足天体测量和天体物理原因所需的高角分辨率，需要滤光片测光。 低色散光谱存在问题，因为在高恒星密度下无法正常工作。 由于预计的恒星数量更多，这将是GaiaNIR比Gaia更严重的问题。 本文的目的是收集所有可以用文字表达的关于GaiaNIR测光的论点，以与读者进行交流。 为了定义卫星上的测光设备，还需要进一步的定量评估和各种选项的比较。 最后，1）滤光片的优势在于测光观测也可用于天体测量， 2）Gaia中的XP光谱将为大约4亿颗G <~ 18.5星等的单恒星提供非常好的天体物理数据，但对所有更暗和所有多重恒星来说，滤光片会更好， 3）目前尚不清楚近红外低色散光谱在天体物理学方面相对于滤光片有什么优势。 显示英文摘要

摘要： Some ideas for onboard processing and photometry with an astrometry satellite are presented, especially designed for GaiaNIR which may be launched about 2045 as a successor of Gaia. - Increased sensitivity, reduced image overlap, and simpler PSF calibration in GaiaNIR will result if the proposed initial processing of data from the detectors is implemented, because the across-scan smearing will become insignificant. - Filter photometry is required for high angular resolution as needed for astrometric and astrophysical reasons. Low-dispersion spectra are questioned because they fail at high star density. This will be a much greater problem with GaiaNIR than it is with Gaia because of the larger number of stars expected. It was the aim to collect in this note all arguments about GaiaNIR photometry which can be stated with words only, in correspondence with readers. The remaining work to be done for the definition of photometric equipment on the satellite requires further quantitative assessments and comparison of various options. Finally, 1) an advantage of filters is that the photometric observations can also be used for astrometry, 2) the XP spectra in Gaia will give very good astrophysical data for about 400 million single stars with G <~ 18.5 mag, but filters would have been better for all fainter and for all multiple stars, and 3) it is presently not clear which advantages for astrophysics low-dispersion spectra in the NIR might have over filters.