二元通量校准器揭示短积分JWST MIRI成像直接探测亚木星系外行星的科学潜力
A Binary Flux Calibrator Reveals the Scientific Potential of Short-integration JWST MIRI Imaging to Directly Detect sub-Jupiter Exoplanets
- Eureka Scientific Inc.（Eureka科学公司）
- University of Michigan（密歇根大学）
- Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）
- University of California Santa Cruz（加州大学圣克鲁兹分校）
- Massachusetts Institute of Technology（麻省理工学院）
- Johns Hopkins APL（约翰斯·霍普金斯大学应用物理实验室）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
利用短积分非日冕仪JWST MIRI成像探测到HD 101452的恒星伴星，证明该方法可高效直接探测邻近恒星周围的亚木星质量冷巨行星。
AI中文摘要：
我们报告了对HD 101452（HIP 56925；Gaia DR3 5384905720847544192）的恒星伴星的直接成像探测，HD 101452是一颗历史上用作红外通量校准器的A型恒星。该伴星是通过在15至25.5微米范围内使用短积分（<1分钟）、非日冕仪JWST MIRI成像，从恒星PSF的不对称性中识别出来的，这些成像数据是绝对通量校准计划CAL 4496的一部分。我们在四个MIRI成像滤光片中探测到该恒星伴星，其投影间距为1.3角秒，中红外通量比约为27倍，因此有必要将其从JWST通量校准器系统中移除。这一探测还表明，当存在与科学目标通量水平紧密匹配的参考星时，非日冕仪MIRI成像可以在小于3λ/D的间距下恢复伴星。利用校准数据中测得的对比度曲线，我们评估了对于邻近恒星（<30 pc）中与HD 101452亮度相当（W4 ~ 6.8星等）的、直接成像社区感兴趣的恒星，通过类似的短MIRI观测所能达到的预测灵敏度。我们发现，如果使用通量紧密匹配的参考星进行PSF减法，仅17-42秒的积分时间就能够在太阳系类似的间距下探测到邻近系统子集中的亚木星质量行星。这些结果表明，分钟级、非日冕仪MIRI观测可以为探索邻近恒星周围的冷巨行星种群提供一条强大而高效的新途径。
英文摘要：
We report the direct imaging detection of a stellar companion to HD 101452 (HIP 56925; Gaia DR3 5384905720847544192), an A star historically used as an infrared flux calibrator. The companion was identified from an asymmetry in the stellar PSF using short-integration (<1 min), noncoronagraphic JWST MIRI imaging from 15 - 25.5$μ$m that was obtained as part of the absolute flux calibration program CAL 4496. We detect the stellar companion in four MIRI imaging filters at a projected separation of 1.3 arcsec with a mid-infrared flux ratio of approximately $27\times$ warranting its removal from the ensemble of JWST flux calibrator systems. This detection also demonstrates that noncoronagraphic MIRI imaging can recover companions at separations below $3λ/D$ when a reference star with a closely matched flux level to the science target is available. Using the measured contrast curves from the calibration data, we evaluate the predicted sensitivity achievable with similar short MIRI observations for nearby stars (<30 pc) that are of interest to the direct-imaging community with comparable brightness to HD 101452 (W4 ~ 6.8 mag). We find that integrations of only 17-42 s are be capable of detecting sub-Jupiter-mass planets at solar system-like separations around a subset of neighboring systems if the PSF subtraction is conducted with closely flux-matched references. These results demonstrate that minutes-length, noncoronagraphic MIRI observations can provide a powerful and efficient new avenue for exploring the cold giant planet population around nearby stars.
