arXiv 2601.047692026-01-08astro-ph.SRastro-ph.GA

金属丰度对经典造父变星周期-亮度定律影响的效应

The effect of metallicity on the Leavitt Law using phase-dependent properties of classical Cepheids

Cotton University（科顿大学）；State University of New York Oswego（纽约州立大学奥斯威戈分校）；European Space Agency (ESA), ESA Office, Space Telescope Science Institute（欧洲空间局（ESA），ESA办公室，太空望远镜科学研究所）；Inter University Centre for Astronomy & Astrophysics（大学间天文学与天体物理学中心）；INAF-Osservatorio astronomico di Capodimonte（意大利国家天体物理研究所卡波迪蒙特天文台）；Yale University（耶鲁大学）

Gautam Bhuyan, Shashi Kanbur, Sukanta Deb, Louise Breuval, Anupam Bhardwaj, Mami Deka, Earl P. Bellinger, Kerdaris Kurbah

备注：: Accepted for publication by MNRAS on 2026 January 5. Received 2025 December 18; in original form 2025 June 2 20 pages, 16 figures
DOI：: 10.1093/mnras/stag038

阅读 PDF

arXiv 页面 ↗HTML 原文 ↗

AI总结：

本文研究了金属丰度对造父变星周期-亮度定律的影响，通过多相分析揭示了不同相位下的金属丰度系数变化，为约束脉动模型提供了新见解。

摘要：

银河系（MW）及其邻近星系中的造父变星周期-亮度（PL）关系的绝对校准一直是确定星系际距离和当前局部宇宙膨胀率的基石。然而，PL关系的普遍性仍存在争议；特别是金属丰度对造父变星PL关系的影响。由于造父变星的HIF-恒星光球相互作用，在不同相位下不同的周期-颜色（PC）关系会影响相应相位下的PL关系。我们考虑了多个脉动相位下的PL关系，因为它们捕捉了这些相位下的整体辐射水动力学性质。我们基于MW、大麦哲伦云（LMC）和小麦哲伦云（SMC）中的经典造父变星光变曲线的多相分析，研究了金属丰度对PL关系的影响。在五个不同的光度学波段（V，I，G，G_BP，G_RP）和两个Wesenheit指数（W_VI，W_G）中，推导出多相金属丰度系数（γ）。我们证明，多相周期-亮度-金属丰度（PLZ）关系的系数会随着造父变星脉动相位的变化而动态变化。我们发现，在多个相位、两个波段（G_RP和W_G）中，短周期（0.4 ≤ logP < 1）和长周期（1 ≤ logP < 2）造父变星的γ_λ值存在显著差异。多相γ_λ值的加权平均值与文献中最新结果一致。我们的方法和结果为金属丰度对Leavitt定律的影响提供了新的见解，这可以用于约束脉动模型。此外，本研究还表明，金属丰度对平均光PL关系的影响可以从本研究中发现的相依赖性质中恢复。

英文摘要：

The absolute calibration of period-luminosity (PL) relations of Cepheids in the Milky Way (MW) and its nearby galaxies has been a cornerstone in determining extragalactic distances and the current local expansion rate of the Universe. However, the universality of PL relations is still debated; particularly, the metallicity effect on the Cepheid PL relation. Due to the HIF-stellar photosphere interactions in Cepheids, different period-color (PC) relations at different phases can influence the corresponding PL relations at those phases.We have considered the PL relations at multiple pulsation phases as they capture the ensemble radiation hydrodynamic properties at those phases. We investigate the effect of metallicity on PL relations based on multiphase analysis of classical Cepheid light curves in the MW, Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC). Multiphase metallicity coefficients $(γ)$ are derived in five different photometric bands ($V$, $I$, $G$, $G_{\rm BP}$, $G_{\rm RP}$) and two Wesenheit indices ($W_{VI}$, $W_{G}$). We show that the coefficients of multiphase period-luminosity-metallicity (PLZ) relations vary dynamically as functions of Cepheid pulsation phases over a complete pulsation cycle. We find significant differences in the $γ_λ$ values between the short- $(0.4 \leq \log{P} < 1)$ and long-period $(1 \leq \log{P} < 2)$ Cepheids at multiple phases, in two bands, $G_{\rm RP}$ and $W_{G}$. The weighted averages of the multiphase $γ_λ$ values are found to be in good agreement with the latest results published in the literature. Our methods and results provide new insights into the metallicity effect on the Leavitt law, which can be useful in constraining pulsation models. Additionally, this study shows that the metallicity effect on mean-light PL relations can be recovered from its phase-dependent nature found in this study.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

AI总结：

摘要：

英文摘要：

相关论文