标题： 向利用詹姆斯·韦伯太空望远镜/中红外仪器的中分辨率光谱仪进行系外行星凌日光谱学的研究 显示英文标题

标题： Toward Exoplanet Transit Spectroscopy Using JWST/MIRI's Medium Resolution Spectrometer

摘要： 中红外仪器（MIRI）的中分辨率光谱仪（MRS）在詹姆斯·韦布空间望远镜（JWST）上对于系外行星的凌星和掩食光谱学具有潜在的重要优势，包括对明亮恒星没有饱和，波长范围延伸至20微米以上，以及JWST最高的光谱分辨率。我们在此通过观测明亮的恒星食双星R Canis Majoris的二次掩食来测试MRS在时间序列光谱学中的性能。我们的观测使MRS在最短波长处达到饱和，这比目前任何已知的系外行星系统都要严重。我们发现像素之间存在强烈的电荷迁移，我们通过使用自定义的数据分析流程来缓解这一问题。我们的数据分析通过按组级别组合探测器像素并根据点扩散函数进行加权，恢复了大部分的空间电荷迁移。我们在5.2微米以上的波长实现了接近光子限制的时序数据性能。2017年，Snellen等人建议MRS可用于检测围绕比邻星运行的温带行星大气中的二氧化碳吸收。我们认为MRS相对于波长的相对光谱响应足够稳定，使得该检测成为可能。关于这种阿尔戈尔型双星的二次掩食，我们通过在四个通道的波长范围内对光谱求和来测量掩食深度，并且还测量了TESS观测到的掩食深度。这些掩食深度需要次级恒星有一个明显比光学到近红外以前观测结果更热的温度，可能是由于主恒星的照射。在MRS的全光谱分辨率下，我们在次级恒星中发现了来自主量子数n = 7、8、10和14的原子氢复合发射线。 显示英文摘要

摘要： The Mid-Infrared Instrument (MIRI)'s Medium Resolution Spectrometer (the MRS) on JWST has potentially important advantages for transit and eclipse spectroscopy of exoplanets, including lack of saturation for bright host stars, wavelength span to longward of 20 microns, and JWST's highest spectral resolving power. We here test the performance of the MRS for time series spectroscopy by observing the secondary eclipse of the bright stellar eclipsing binary R Canis Majoris. Our observations push the MRS into saturation at the shortest wavelength, more than for any currently known exoplanet system. We find strong charge migration between pixels that we mitigate using a custom data analysis pipeline. Our data analysis recovers much of the spatial charge migration by combining detector pixels at the group level, via weighting by the point spread function. We achieve nearly photon-limited performance in time series data at wavelengths longward of 5.2 microns. In 2017, Snellen et al. suggested that the MRS could be used to detect carbon dioxide absorption from the atmosphere of the temperate planet orbiting Proxima Centauri. We infer that the relative spectral response of the MRS versus wavelength is sufficiently stable to make that detection feasible. As regards the secondary eclipse of this Algol-type binary, we measure the eclipse depth by summing our spectra over the wavelengths in four channels, and also measuring the eclipse depth as observed by TESS. Those eclipse depths require a temperature for the secondary star that is significantly hotter than previous observations in the optical to near-IR, probably due to irradiation by the primary star. At full spectral resolution of the MRS, we find atomic hydrogen recombination emission lines in the secondary star, from principal quantum levels n = 7, 8, 10, and 14.