利用年轻恒星天体追踪英仙座分子云中由膨胀驱动的恒星形成
Tracing expansion-driven star formation in the Perseus molecular cloud using young stellar objects
AI总结：
该研究对英仙座406个年轻恒星天体开展六维相空间分析，证实珀尔-金牛座壳的历史膨胀触发了英仙座分子云内分层、由内向外的序列恒星形成。
AI中文摘要：
背景：近期研究将太阳邻近区域的恒星形成与本地泡的膨胀关联起来；珀尔-金牛座壳（PTS）是一个巨大的三维尘埃结构，英仙座和金牛座分子云位于其表面，是此类触发形成的候选结构。目标：我们旨在重建英仙座分子云的恒星形成历史，并探究其与PTS历史膨胀的潜在关联。方法：我们对英仙座的406个年轻恒星天体（YSO）进行了六维相空间分析；该方法结合了盖亚DR3的运动学数据、贝叶斯年龄推断以及异方差似然框架，以解析YSO年龄相对于PTS中心的径向梯度和本征切向速度弥散；我们整合了现有基于红外的分类，构建了统一星表，以研究不同演化阶段的投影空间 segregation，并将恒星三维运动学与$^{12}$CO和$^{13}$CO气体速度场进行比较，评估运动学连贯性。结果：YSO相对于PTS中心呈现出连贯的向外运动，存在负的年龄-距离梯度（更大半径处的恒星群更年轻），且切向速度弥散随径向距离递减；更年轻的YSO类别还表现出更强的朝向PTS中心的方向集中度；这些YSO的连贯自行和视线速度梯度均与气体速度场对齐，表明存在大规模运动学连贯性。结论：英仙座YSO表现出与膨胀起源一致的运动学和时间特征；这些结果为分层、由内向外的恒星形成模式提供了有力证据，表明PTS的历史膨胀触发了恒星诞生的序列进展，有效塑造了英仙座复合体的恒星形成历史。
英文摘要：
$Context$. Recent studies have linked star formation in the solar neighbourhood to the expansion of the Local Bubble. The Per-Tau Shell (PTS), a vast 3D dust structure hosting the Perseus and Taurus clouds on its surface, is a candidate for such triggered formation. $Aims$. We aim to reconstruct the star formation history of the Perseus molecular cloud and investigate its potential link to the historical expansion of the PTS. $Methods$. We performed a 6D phase-space analysis of 406 young stellar objects (YSOs) of Perseus. Our approach integrates Gaia DR3 kinematics with Bayesian age inference and a heteroscedastic likelihood framework to resolve radial gradients in YSO ages and intrinsic tangential velocity dispersions relative to the PTS centre. We constructed a unified catalogue by integrating existing infrared-based classifications to examine the projected spatial segregation of different evolutionary stages and compared stellar 3D kinematics with $^{12}$CO and $^{13}$CO gas velocity fields to assess kinematic coherence. $Results$. The YSOs exhibit coherent outward motions relative to the centre of the PTS, a negative age-distance gradient with younger populations at larger radii, and a radial decline in tangential velocity dispersions. Younger YSO classes also show a stronger directional concentration towards the PTS centre. Both the coherent proper motions and the line-of-sight velocity gradients of these YSOs align with the gas velocity field, indicating large-scale kinematic coherence. $Conclusions$. The Perseus YSOs exhibit concordant kinematic and temporal signatures consistent with an expansion-driven origin. These results provide robust evidence for a layered, inside-out pattern of star formation, suggesting that the historical expansion of the PTS triggered a sequential progression of star birth and effectively shaped the star formation history of the Perseus complex.
