AI 中文总结
本研究构建了适配JWST与Roman系统的经典造父变星理论框架，推导了相关关系并与观测吻合，为高精度距离标度研究提供了校准与理论支撑。
AI 中文摘要
经典造父变星是基础距离指示器，通过周光关系、周光色关系和周韦森关系锚定宇宙距离阶梯，同时也能为年轻恒星族群提供重要约束。近期空间近红外观测的进展凸显了针对现代测光系统中经典造父变星可观测值进行理论校准的需求，这类测光系统专为精度距离标度应用优化。本研究为JWST/NIRCam和Roman/WFI系统中的经典造父变星提供了均匀的理论框架，并探索其作为近红外标准烛光的应用。我们利用涵盖广泛质量、有效温度、周期、金属丰度、对流效率及质光关系的非线性对流脉动模型的大规模网格，推导了平均星等、颜色、脉动振幅、振幅比，以及新的理论周光色关系、周韦森关系和与金属丰度相关的周韦森关系。将理论韦森关系与SH0ES合作组在6个Ia型超新星宿主星系中获取的经典造父变星的近期JWST观测结果对比，发现预测与观测结果吻合度极高，最大系统效应源于所采用的质光关系。当采用轻度超亮的质光关系而非标准质光关系时，理论距离模数与经验JWST测定结果完全一致。这些结果为JWST和Roman观测提供了基于脉动的自洽校准，也为未来本地距离标度的高精度研究提供了理论框架。
英文摘要
Classical Cepheids are fundamental distance indicators that anchor the cosmic distance ladder through their Period-Luminosity, Period-Luminosity-Color, and Period-Wesenheit relations, while also providing valuable constraints on young stellar populations. Recent advances in space-based near-infrared observations highlight the need for theoretical calibrations of Classical Cepheid observables in modern photometric systems optimized for precision distance-scale applications. This work provides a homogeneous theoretical framework for Classical Cepheids in the JWST/NIRCam and Roman/WFI systems and explores their use as standard candles in the near-infrared. We exploit an extensive grid of nonlinear convective pulsation models spanning a broad range of masses, effective temperatures, periods, metallicities, convective efficiencies, and mass-luminosity relations. We derive mean magnitudes, colors, pulsation amplitudes, amplitude ratios, and new theoretical Period-Luminosity-Color, Period-Wesenheit, and metal-dependent Period-Wesenheit relations. The theoretical Wesenheit relations are compared with recent JWST observations of Classical Cepheids in six SN Ia host galaxies from the SH0ES collaboration. We find excellent agreement between predictions and observations, with the largest systematic effects arising from the adopted mass-luminosity relation. Theoretical distance moduli are fully consistent with empirical JWST determinations when a mildly overluminous mass-luminosity relation is adopted instead of the canonical one. These results provide a self-consistent pulsation-based calibration for JWST and Roman observations and a theoretical framework for future precision studies of the local distance scale.
Comments22 pages, including appendices, 21 figures, 10 tables. Accepted for publication in Astronomy & Astrophysics, Section 7: Stellar Structure and Evolution
