波前条件光子测量用于系外行星光谱：对比度极限与条件增益
Wavefront-Conditioned Photon Measurements for Exoplanet Spectroscopy: Contrast Limits and Conditional Gains
- Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究提出波前条件光子测量方法，通过预测选择或条件化测量以优化系外行星反射光光谱观测，在泄漏主导背景下实现对比度极限与条件增益，优于固定测量方案。
AI中文摘要：
波前传感器（WFS）的预测可以在探测之前选择光子测量方式，或在探测之后对其似然进行条件化。这对于需要数百小时观测的反射光光谱至关重要，因为减去残余星光无法消除其光子噪声。在双模、低占用模型中，各向同性分布的泄漏使得行星模式投影——与行星匹配的理想单模注入——成为最优的固定单光子测量方式，包括不等的对齐背景和每个输出端相等的泊松探测器事件率。对于非零泄漏，一种可达到的双输出条件测量是最优的，并且在差分损失之前严格更具信息量。对于各向同性背景，对于任何记录的泄漏方向分布，对比度界限成立：相对透射率0.80和相对允许时间占空比0.90将每计划时间的Fisher信息限制为固定最优值的0.81（在可预测泄漏和行星对比度相等时）。Haar平均将此上限收紧至0.78。获得增益所需的泄漏与行星比约为：任意方向律为2.25，Haar方向为3.26。一种浓度模型证书识别出足以击败重新校准的固定测量的方向多样性。独立门控的固定基后备方案在速率和成本已知时保证不丢失连续轮廓光谱信息。对于宜居世界天文台，候选机制是可预测的、方向多样的、泄漏主导的残余，而非一般的灵敏度提升。
英文摘要：
A wavefront-sensor (WFS) prediction can select the photon measurement before detection or condition its likelihood afterward. This matters for reflected-light spectra requiring hundreds of hours, because subtracting residual starlight cannot remove its photon noise. In a two-mode, low-occupation model, isotropically distributed leakage makes planet-mode projection---ideal single-mode injection matched to the planet---the optimal fixed single-photon measurement, including unequal aligned backgrounds and equal Poisson detector-event rates per output. For nonzero leakage, an attainable two-output conditioned measurement is optimal and strictly more informative before differential loss. For an isotropic background, a contrast bound holds for any distribution of recorded leakage directions: relative transmission $0.80$ and relative admitted-time duty $0.90$ limit the Fisher information per scheduled time to $0.81$ of the fixed optimum at equal predictable-leakage and planet contrasts. Haar averaging sharpens this ceiling to $0.78$. The necessary leakage-to-planet ratios for gain are approximately $2.25$ for any direction law and $3.26$ for Haar directions. A concentration-model certificate identifies directional diversity sufficient to beat recalibrated fixed measurements. Independently gated fixed-basis fallback guarantees no loss of continuum-profiled spectral information when rates and costs are known. For the Habitable Worlds Observatory, the candidate regime is predictable, directionally diverse, leakage-dominated residuals, not a general sensitivity improvement.
