欧几里得：利用天炉座星系团早期发布观测数据校准表面亮度波动距离
Euclid: Calibrating distances from surface brightness fluctuations with Early Release Observations of the Fornax cluster
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中文总结 AI 辅助
研究利用表面亮度波动（SBF）结合FAST - SBF代码，基于欧几里得数据校准天炉座星系团等星系的距离，测试校准关系并与文献及模型比较，可用于探测星系潜在恒星群体，为星系研究提供新方法。
中文摘要 AI 辅助
表面亮度波动（SBF）是星系图像中恒星统计分布引起的通量像素间变化，能仅从光度数据测量与红移无关的距离，在大型成像巡天时代很重要。本文首次将SBF应用于欧几里得数据，用FAST - SBF代码测量天炉座星系团早期发布观测中星系样本在$I_\mathrm{E}$波段的恒星波动幅度。虽数据约简管道未针对SBF测量优化，但经广泛测试能提取可靠结果。校准了天炉座15个星系的绝对波动星等$\overline{M}_\mathrm{IE}$与$(I_\mathrm{E}{-}H_\mathrm{E})$颜色的关系，并在另外两个早期发布观测场进行测试。与文献中的距离有合理一致性，在FAST - SBF表明测量可靠的情况下一致性良好。最后将结果与恒星群体工具简单恒星群体模型比较，探讨了用欧几里得的SBF探测星系潜在恒星群体的可能性。
英文摘要
Surface brightness fluctuations (SBF), the pixel-to-pixel variations in flux that arise from the statistical distribution of stars in galaxy images, provide a powerful tool to measure redshift-independent distances from photometric data alone. This method is particularly important in the era of large imaging surveys, such as those carried out during the Euclid mission. Here we present the first application of SBF to Euclid data, using the FAST-SBF code to measure stellar fluctuation amplitudes in the $I_\mathrm{E}$ band for a sample of galaxies in the Early Release Observations (ERO) of the Fornax galaxy cluster. Although the Euclid data reduction pipeline is not optimized for SBF measurements, extensive testing suggests that we are able to extract robust results. We calibrate the absolute fluctuation magnitude $\overline{M}_\mathrm{IE}$ as a function of the $(I_\mathrm{E}{-}H_\mathrm{E})$ colour for 15 galaxies in Fornax, then test this relation on galaxies in two other ERO fields: the Perseus cluster and dwarf satellite candidates around NGC 6744. Overall, we find reasonable agreement with distances in the literature and good agreement in cases where FAST-SBF indicates the measurements are robust. Finally, we compare our results against Stellar Population Tools (SPoT) simple stellar population models, and discuss the possibility of using SBF with Euclid to probe the underlying stellar populations of the galaxies.
