AI 中文总结
研究 WFC3/IR 通道灵敏度损失，通过对 47 Tucanae 和梅西耶 4 星团观测，增加额外观测次数，得出不同数据集及曝光下的灵敏度损失率，发现损失率下降，指出早期观测或高估灵敏度，参考文件未变。
AI 中文摘要
WFC3/IR 通道随时间推移会失去灵敏度。过去的工作已对灵敏度损失率进行了量化，本文利用 47 Tucanae 和梅西耶 4 星团在 F110W 和 F160W 滤镜下未拥挤区域的光度测量，将这些测量扩展到 2026 年。自 Bajaj 等人（2022 年）以来，每个目标/滤镜组合增加了 4 - 7 次额外观测。利用 47Tuc 的 F160W 数据，通过完整数据集发现红外通道每年以 -0.07% ± 0.01% 的速率失去灵敏度，仅使用每次观测的首次曝光时为 -0.06% ± 0.02%。利用 F110W 观测的 M4 数据，完整数据集下灵敏度损失率为 -0.13% ± 0.02%，仅首次曝光时为 -0.07% ± 0.03%。灵敏度损失率自上次研究以来有所下降，可能是因为纳入了旨在减轻残留效应的更新观测。结果表明，早期非用于灵敏度测量的观测可能因亮源残留效应高估了红外通道的灵敏度。包含随时间变化灵敏度校正的 IMPHTTAB 参考文件与本报告的灵敏度测量结果保持不变。
英文摘要
The WFC3/IR channel has been shown to lose sensitivity over time. The sensitivity loss rate has been quantified in past works and we extend those measurements into 2026 using photometry of uncrowded regions of star clusters 47 Tucanae and Messier 4 in the F110W and F160W filters. This study adds 4-7 additional visits since Bajaj et al. (2022) for each target/filter combination. Using F160W data of 47Tuc, we find that the IR channel continues to lose sensitivity at a rate of -0.07% $\pm$ 0.01% per year using the full dataset, and -0.06% $\pm$ 0.02% per year using only the first exposure of every visit. Using M4 data observed in F110W, we find a sensitivity loss rate of -0.13% $\pm$ 0.02% per year using the full dataset, and -0.07% $\pm$ 0.03% per year using just the first exposure of every visit. We find that the rate of sensitivity loss has decreased since the previous study. This likely stems from the inclusion of more recent visits that were designed to mitigate persistence effects. These results suggest that earlier observations, which were not intended for sensitivity measurements, may have overestimated the IR channel's sensitivity due to the effects of persistence from bright sources. The IMPHTTAB reference file that contains the correction to the time-dependent sensitivity remains unchanged from the sensitivity measurements of this report.
Comments13 pages, 9 figures
