发表机构
California Institute of Technology; Zentrum für Astronomie der Universität Heidelberg; Institut für Theoretische Physik und Astrophysik, Christian-Albrechts-Universität zu Kiel; Department of Astronomy and Astrophysics, Penn State University; Space Telescope Science Institute; CRESST II and X-ray Astrophysics Laboratory NASA/GSFC; Institute for Astrophysics and Computational Sciences, The Catholic University of America; Department of Astronomy, Graduate School of Science, The Univers（加州理工学院; 海德堡大学天文中心; 基尔大学理论与天体物理研究所; 宾夕法尼亚州立大学天文与天体物理系; 太空望远镜科学研究所; NASA/戈达德太空飞行中心 CRESST II 与 X射线天体物理实验室; 美利坚天主教大学天体物理与计算科学研究所; 大学理学研究生院天文系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用JWST观测NGC 2403中亚太阳金属丰度区域的WC双星候选体SPIRITS 19q，测得其高尘埃产生率，证实此类系统是早期宇宙碳质尘埃的重要来源。
AI 中文摘要
我们呈现了JWST/NIRSpec积分场单元（IFU）对SPIRITS 19q的观测结果，SPIRITS 19q是位于近邻旋涡星系NGC 2403的亚太阳金属丰度区域内的一个高尘埃产生率的富碳（WC型）双星候选体。2024年4月获取的观测结果证实，斯皮策空间望远镜在2019年观测到的尘埃爆发与一颗早型WC星相关。利用波茨坦沃尔夫-拉叶星（PoWR）大麦哲伦云（LMC）模型网格，我们发现SPIRITS 19q的WC星很可能具有极高的质量损失率（≥10⁻⁴ M⊙/年）。根据斯皮策/IRAC测得的红外暂现源流量峰值，以及JWST光谱对尘埃成分和尺寸的约束，我们估算此次爆发中形成的尘埃总质量为6.6±0.4×10⁻⁶ M⊙。假设轨道周期最小值为12年，这对应于周期平均尘埃产生率≤5.5×10⁻⁷ M⊙/年。这些观测结果表明，即使是单个WC系统也能在亚太阳金属丰度环境中为尘埃预算做出贡献，且此类系统是早期宇宙中碳质尘埃颗粒的重要来源。
英文摘要
We present JWST/NIRSpec IFU observations of SPIRITS 19q, the highly dust-producing carbon-rich (WC) binary candidate located in a subsolar-metallicity region of the nearby spiral galaxy NGC 2403. The observations, taken in April of 2024, confirm the association of a dusty outburst observed in 2019 by the Spitzer Space Telescope with an early-type WC star. Using models from the Potsdam Wolf-Rayet (PoWR) LMC model grid we find that the WC star of SPIRITS 19q likely has an especially high mass-loss rate ($\gtrsim$ 10$^{-4}$ $M_{\odot}$ yr$^{-1}$). From the flux peak of the IR transient as measured by Spitzer/IRAC as well as constraints on dust composition and size from the JWST spectrum, we estimate a total dust mass formed in the outburst of 6.6 $\pm$ 0.4 $\times$ 10$^{-6}$ $M_{\odot}$. Assuming a minimum orbital period of 12 years, this corresponds to a period-averaged dust production rate of $\lesssim$ 5.5 $\times$ 10$^{-7}$ $M_{\odot}$ yr$^{-1}$. These observations suggest that even a single WC system can contribute to the dust budget at subsolar metallicities, and that such systems are an important source of carbonaceous dust grains in the early universe.
Comments14 pages, 6 figures, accepted to Publications of the Astronomical Society of the Pacific (PASP)
