Microlens parallax measurements combining space-based and ground-based observatories can be used to study planetary demographics. In recent years, the Spitzer Space Telescope was used as a microlens parallax satellite. Meanwhile, Spitzer IRAC has been employed to study short-period exoplanets and their atmospheres. As these investigations require exquisite photometry, they motivated the development of numerous self-calibration techniques now widely used in the exoplanet atmosphere community. Specifically, pixel level decorrelation (PLD) was developed for starring-mode observations in uncrowded fields. We adapt and extend PLD to make it suitable for observations obtained as part of the Spitzer Microlens Parallax Campaign. We apply our method to two previously published microlensing events, OGLE-2017-BLG-1140 and OGLE-2015-BLG-0448, and compare its performance to the state-of-the-art pipeline used to analyses Spitzer microlensing observation. We find that our method yields photometry 1.5–6 times as precise as previously published. In addition to being useful for Spitzer, a similar approach could improve microlensing photometry with the forthcoming Nancy Grace Roman Space Telescope.

中文翻译：

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斯皮策微透镜视差调查服务中的像素级去相关

结合天基和地面天文台的微透镜视差测量可用于研究行星人口统计。近年来，斯皮策太空望远镜被用作微透镜视差卫星。与此同时，斯皮策 IRAC 已被用于研究短期系外行星及其大气。由于这些调查需要精细的光度测量，因此它们推动了许多自校准技术的发展，这些技术现在广泛应用于系外行星大气界。具体来说，像素级去相关 (PLD) 是为在不拥挤的领域中的主演模式观察而开发的。我们调整并扩展了 PLD，使其适用于作为 Spitzer 微透镜视差运动的一部分获得的观察结果。我们将我们的方法应用于两个先前发布的微透镜事件，OGLE-2017-BLG-1140 和 OGLE-2015-BLG-0448，并将其性能与用于分析 Spitzer 微透镜观察的最先进管道进行比较。我们发现我们的方法产生的光度测量精度是以前发表的 1.5-6 倍。除了对斯皮策有用之外，类似的方法还可以通过即将推出的南希格雷斯罗马太空望远镜改进微透镜测光。