发表机构
Northwestern University; University of Toronto; University of Florida; INAF(西北大学; 多伦多大学; 佛罗里达大学; 意大利国家天体物理研究所)
机构由 AI 辅助整理,请以论文原文为准。AI 中文总结
基于JWST NIRCam成像,对20 Mpc内15个星系的约10万颗红超巨星进行最大规模种群研究,开发新流程与聚类方法,发现环境塑造演化及一批极端红超巨星。
AI 中文摘要
红超巨星(RSG)的演化,尤其是在其作为富氢II型超新星(SNe)爆发前的最终阶段,由于本星系群中特征明确的恒星样本较小,至今仍知之甚少。我们利用从詹姆斯·韦布空间望远镜/近红外相机(NIRCam)对20 Mpc内15个星系的档案成像中推断出的热光度参数,对约10^5颗恒星进行了迄今最大规模的红超巨星种群研究。我们还介绍了jwst123,这是一个新开发的通用NIRCam数据归约与测光流程,并将其应用于我们的15个星系样本。我们构建了一个基于模拟的参数推断框架,以毫秒级速度快速拟合约150万颗发光恒星的多波段测光数据。利用有效温度($T_{\rm eff}$)-光度($\log L/L_{\odot}$)-尘埃光学深度($\tau_V$)相空间中的聚类,我们引入了一种新的方法,以高完备性和高纯净度选择红超巨星。利用我们星表的规模,我们发现最尘埃笼罩的红超巨星倾向于存在于富金属宿主星系中,且红超巨星光度与宿主星系特定恒星形成率相关,表明环境塑造了红超巨星的演化。虽然大多数选定的红超巨星与理论恒星演化轨迹一致,但我们识别出一个包含1,669颗红超巨星的新种群,它们被尘埃严重包裹($\tau_V>4$)、过度发光($\log(L/L_{\odot})>5.55$)或异常低温($T_{\rm eff}<3000\\,{\rm K}$),其中包括已知超新星前身星的类似体。我们的星表为理解大质量恒星演化以及将场红超巨星与II型超新星的尘埃前身星联系起来,提供了种群尺度的基线。
英文摘要
The evolution of red supergiants (RSGs), especially in their final stages before exploding as hydrogen-rich Type II supernovae (SNe), remains poorly understood, owing to small samples of well-characterized stars in the Local Group. We present the largest population study of RSGs to date using $\sim10^5$ stars with bolometric parameters inferred from archival James Webb Space Telescope/Near-Infrared Camera (NIRCam) imaging of 15 galaxies within 20 Mpc. We also present jwst123, a newly-developed general-purpose NIRCam reduction and photometry pipeline, and its application to our set of 15 galaxies. We build a simulation-based parameter inference framework to rapidly fit multi-band photometry of $\sim1.5$ million luminous stars in milliseconds per source. Using clustering in the effective temperature ($T_{\rm eff}$)-luminosity ($\log L/L_{\odot}$)-dust optical depth ($τ_V$) phase space, we introduce a novel method to select RSGs with high completeness and purity. Leveraging the scale of our catalog, we find that the dustiest RSGs prefer metal-rich hosts, and RSG luminosities correlate with host specific star formation rate, suggesting that environment shapes RSG evolution. While most selected RSGs agree with theoretical stellar evolution tracks, we identify a new population of 1,669 RSGs that are heavily dust-enshrouded ($τ_V>4$), overluminous ($\log(L/L_{\odot})>5.55$), or anomalously cool ($T_{\rm eff}<3000\,{\rm K}$), including analogs of known SN progenitors. Our catalog provides a population-scale baseline for understanding massive stellar evolution and connecting field RSGs to dusty progenitors of Type II SNe.
Comments43 pages, 25 figures