罗马焦平面上的色效应：对超新星光度测量和宇宙学参数测量的影响
Chromatic Effects Across the Roman Focal Plane: Implications for Supernova Photometry and Measurements of Cosmological Parameters
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中文总结 AI 辅助
研究罗马太空望远镜色效应，通过模拟光曲线量化其对超新星Ia光度测量及宇宙学参数的影响，分析波长相关偏差来源，结果表明FPA相关偏移影响大，需精确到20%以内，而滤光片校准偏移影响可忽略，色效应是该望远镜宇宙学研究必要部分。
中文摘要 AI 辅助
校准不确定性是使用Ia型超新星（SNe Ia）进行宇宙学分析中的主要系统误差。对于南希·格雷斯·罗马太空望远镜（Roman），我们使用高纬度时域调查的模拟光曲线，量化了色效应对SNe Ia光度测量和导出的宇宙学参数的影响。我们研究了两个波长相关偏差的来源：Roman的18个探测器上空间变化引起的焦平面阵列（FPA）相关波长偏移，以及与绝对滤光片波长校准中测量的0.06%不确定性对应的相干波长偏移。使用模拟的SNe Ia光曲线，我们发现FPA相关偏移（范围从+6到-80 Å）引入了与红移相关的距离模数偏差，如果不校正，将传播到Δw0约为-0.06和Δwa = -0.236，这大于预测的统计不确定性σstat,w0 = 0.025和σstat,wa = 0.114，使调查受系统误差限制。我们通过采用特定探测器的滤光曲线来探测色效应的影响，这些曲线恢复了无偏差的宇宙学约束；为了保持在统计噪声水平以下，FPA波长偏移必须精确到20%以内。相比之下，滤光片波长校准中0.06%的相干偏移（范围从-3到-11 Å）产生的与红移相关的偏差可忽略不计，wa的变化最小（Δwa = -0.0004，σw a,sys = 0.114），表明发射前实现的校准精度足以使这种系统误差保持次要地位。我们的结果表明，色效应是使用Roman进行SNe Ia宇宙学研究的必要组成部分。
英文摘要
Calibration uncertainties are the leading systematics in cosmological analyses using Type Ia supernovae (SNe Ia). For the \textit{Nancy Grace Roman Space Telescope (Roman)}, we quantify the impact of chromatic effects on SNe Ia photometry and derived cosmological parameters, using simulated light curves from the High-Latitude Time Domain Survey. We investigate two sources of wavelength-dependent bias: focal plane array (FPA)-dependent wavelength shifts arising from spatial variations across \textit{Roman's} 18 detectors, and coherent wavelength shifts corresponding to the measured $0.06\%$ uncertainty in absolute filter wavelength calibration. Using simulated SNe Ia light curves, we find that the FPA-dependent shifts -- which range from +6 to -80 $\rm Å$ introduce a redshift-dependent distance modulus bias that, if left uncorrected, propagates to $Δw_0 \sim -0.06$ and $Δw_a = -0.236$, which are larger than the forecast statistical uncertainties of $σ_{\rm stat, w_0} = 0.025$ and $σ_{\rm stat, w_a} = 0.114$, rendering the survey systematics-limited. We probe the impact of chromatic effects by employing detector-specific filter curves that recover unbiased cosmological constraints; to remain below the statistical noise floor, FPA wavelength shifts must be characterized to within 20\%. In contrast, a coherent 0.06\% offset in filter wavelength calibration -- ranging from -3 to -11 $\rm Å$ -- produces negligible redshift-dependent bias, with a minimal spread in $w_a$ ($Δw_a = -0.0004, σ_{w_{a,\rm sys}} = 0.114)$, demonstrating that the achieved pre-launch calibration precision is sufficient for this systematic to remain subdominant. Our results establish that chromatic effects are a required component of SN Ia cosmology with \textit{Roman}.
