发表机构
Yunnan Observatories, Chinese Academy of Sciences; University of Chinese Academy of Sciences; International Centre of Supernovae, Yunnan Key Laboratory of Supernova Research, Yunnan Observatories, Chinese Academy of Sciences; School of Physics and Astronomy, Sun Yat-sen University（中国科学院云南天文台; 中国科学院大学; 中国科学院云南天文台超新星研究中心（国际超新星中心、云南省超新星研究重点实验室）; 中山大学物理学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过MESA模型模拟行星吞噬对恒星金属丰度与旋转的影响，发现金属贫乏恒星可长期维持超太阳丰度，而1.0太阳质量恒星是观测吞噬特征的最佳目标。
AI 中文摘要
行星吞噬导致行星质量吸积和角动量沉积到恒星包层中。本研究使用MESA模型来调查吞噬对恒星金属丰度和旋转速度的长期影响，以及旋转混合对金属富集的作用。我们的模型显示，在主序（MS）晚期发生的吞噬比在零年龄主序（ZAMS）时产生显著更高的表面富集。旋转混合通常会抑制富集；然而，金属贫乏恒星可以维持超太阳丰度达数十亿年，而高金属丰度恒星则基本不受影响。尽管吞噬引起瞬时自转加速，但这种角动量注入是瞬态的，恒星很快重新收敛到其标准旋转演化。因此，主序自转加速不能作为长期观测指标。由于对流包层厚度和主序寿命决定了富集的幅度和持续时间，识别吞噬特征需要在0.7太阳质量恒星中长寿命但稀释的信号与1.2太阳质量恒星中强烈但短暂的富集之间进行权衡。因此，1.0太阳质量恒星既提供可观的富集又具有相对较长的主序寿命，是观测搜索的最佳目标。
英文摘要
Planet engulfment leads to planetary mass accretion and angular momentum deposition into the stellar envelope. This study uses MESA models to investigate the long-term impact of engulfment on stellar metallicity and rotational velocity, as well as the effect of rotational mixing on metal enrichment. Our models show that engulfment occurring during the late main-sequence (MS) stage yields significantly higher surface enrichment than at the ZAMS. Rotational mixing generally suppresses enrichment; however, metal-poor stars can sustain super-solar abundances for several Gyr, whereas high-metallicity stars remain largely unaffected. Although engulfment causes an instantaneous spin-up, this angular momentum injection is transient, and the star quickly re-converges to its standard rotational evolution. Thus, MS spin-up cannot serve as a long-term observational indicator. Because convective envelope thickness and MS lifetime dictate the magnitude and duration of enrichment, identifying engulfment signatures requires balancing the long-lived but diluted signals in 0.7 M_sun stars against the strong yet short-lived enrichment in 1.2 M_sun stars. Consequently, 1.0 M_sun stars offering both substantial enrichment and a relatively long MS lifetime represent optimal targets for observational searches.
Comments13 pages, 13figures. Accepted for publication in A&A
