碳星V420 Vul周围的HI包层
HI envelope around the carbon star V420 Vul
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中文总结 AI 辅助
研究利用阿雷西博巡天数据探测到碳星V420 Vul周围秒差距尺度的HI结构，揭示其为恒星风与星际介质相互作用的产物，证实晚期恒星质量损失的运动学记录可在大尺度和长时间标上保留。
中文摘要 AI 辅助
我们利用存档的银河系阿雷西博L波段馈源阵列巡天数据，报告了对米拉变星V420 Vul方向上延展的21厘米秒差距尺度电离氢（\text{ion}{H}{i}）结构的探测结果。该发射呈现空间上连贯但强度不对称的形态，不过仍保留以\textit{v}$_{\text{LSR}}$≈47.6千米每秒为中心的全局对称运动学轮廓。在采用距离约1.9千秒差距的情况下，该结构延展范围约20秒差距，意味着动力学时标约为10$^6$年。尽管总电离氢质量（约70太阳质量）表明原子气体储库主要由周围星际介质主导，而非原始恒星抛射物，但空间分辨光谱与位置-速度图揭示了以恒星为中心的潜在对称速度框架。我们将此解释为恒星风优先通过多孔周围云团通道的动力学印记，证明尽管存在主导性的星际耦合，晚期恒星质量损失的连贯运动学记录仍可在秒差距尺度与百万年时标上得以保留。
英文摘要
We report the detection of an extended 21-cm parsec-scale \ion{H}{i} structure toward the Mira variable V420\,Vul using archival Galactic Arecibo L-band Feed Array survey data. The emission exhibits a spatially coherent but intensity-asymmetric morphology that nevertheless retains a globally symmetric kinematic profile centered near $v_{\mathrm{LSR}} \sim 47.6\,\mathrm{km\,s^{-1}}$. At an adopted distance of $\sim 1.9$\,kpc, the structure extends over $\sim 20$\,pc, implying a dynamical timescale of order $10^6$\,yr. Although the total \ion{H}{i} mass ($\sim 70\,\mathrm{M_\sun}$) indicates that the atomic gas reservoir is heavily dominated by the ambient interstellar medium rather than pristine stellar ejecta, the spatially resolved spectra and position-velocity diagrams reveal an underlying symmetric velocity framework centered on the star. We interpret this as the dynamical imprint of the stellar wind preferentially channeling through a porous ambient cloud, demonstrating that cohesive kinematic records of late-stage stellar mass loss can be preserved over parsec scales and megayear timescales despite dominant interstellar coupling.
