We present the initial design, performance improvements, and science opportunities for an upgrade to the Field-Imaging Far-Infrared Line Spectrometer (FIFI-LS). FIFI-LS efficiently measures fine structure cooling lines, delivering critical constraints of the interstellar medium and star-forming environments. The Stratospheric Observatory for Infrared Astronomy (SOFIA) provides the only far-infrared (FIR) observational capability in the world, making FIFI-LS a workhorse for FIR lines, combining optimal spectral resolution and a wide velocity range. Its continuous coverage of 51 to 203 μm makes FIFI-LS a versatile tool to investigate a multitude of diagnostic lines within our galaxy and in extragalactic environments. The sensitivity and field of view (FOV) of FIFI-LS are limited by its 90s-era photoconductor arrays. These limits can be overcome by upgrading the instrument using the latest developments in kinetic inductance detectors (KIDs). KIDs provide sensitivity gains in excess of 1.4 and allow larger arrays, enabling an increase in pixel count by an order of magnitude. This increase allows a wider FOV and instantaneous velocity coverage. The upgrade provides gains in point source observation speed by a factor >2 and in mapping speed by a factor >3.5, enabled by the improved sensitivity and pixel count. This upgrade has been proposed to NASA in response to the 2018 SOFIA Next Generation Instrumentation call.

中文翻译：

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利用动电感检测器升级用于红外天文学的平流层观测所的场成像远红外光谱仪：能够进行大样本（计测）调查

我们介绍了场成像远红外光谱仪（FIFI-LS）的升级的初步设计，性能改进和科学机会。FIFI-LS有效地测量精细结构的冷却线，从而对星际介质和恒星形成环境提供了严格的限制。平流层红外天文台（SOFIA）提供世界上唯一的远红外（FIR）观测功能，使FIFI-LS成为FIR谱系的主力军，结合了最佳的光谱分辨率和宽广的速度范围。FIFI-LS的连续覆盖范围为51至203μm，使FIFI-LS成为研究我们银河系内和银河外环境中众多诊断线的多功能工具。FIFI-LS的灵敏度和视野（FOV）受其90年代时代的光电导体阵列的限制。通过使用动感检测器（KID）的最新发展来升级仪器，可以克服这些限制。KID提供超过1.4的灵敏度增益，并允许更大的阵列，从而使像素数增加一个数量级。这种增加允许更宽的FOV和瞬时速度覆盖范围。通过提高灵敏度和像素数量，升级使点源观察速度提高了> 2倍，映射速度提高了> 3.5倍。已针对NASA提出的升级建议，以响应2018年SOFIA下一代仪器的电话会议。这种增加允许更宽的FOV和瞬时速度覆盖范围。通过提高灵敏度和像素数量，升级使点源观察速度提高了> 2倍，映射速度提高了> 3.5倍。已针对NASA提出的升级建议，以响应2018年SOFIA下一代仪器的电话会议。这种增加允许更宽的FOV和瞬时速度覆盖范围。通过提高灵敏度和像素数量，升级使点源观察速度提高了> 2倍，映射速度提高了> 3.5倍。已针对NASA提出的升级建议，以响应2018年SOFIA下一代仪器的电话会议。