arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2511.04410astro-ph.EP
收藏

M_d 梯度与紫外场强度的关系如何揭示原行星盘族群年龄的见解

How the gradient of $M_{\rm d}$ versus UV field strength yields insights into the ages of protoplanetary disc populations

Gavin A. L. Coleman, Sierk E. van Terwisga

备注：
Accepted for publication in MNRAS. 7 pages, 4 figures
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

AI总结：

本文利用盘演化模型研究原行星盘中位尘埃质量与外部紫外场强度关系斜率 λ_UV 随时间和恒星质量的变化，发现族群年龄增长使斜率趋于平缓、大质量恒星斜率更陡，并利用 L1641 观测将粘滞参数 α 初步约束在 10^{-3.5} 至 10^{-2.5} 之间。

摘要：

来自大质量恒星的远紫外（FUV）辐射会从其他恒星周围原行星盘的外部区域驱动光致蒸发风，带走气体和尘埃。观测已经发现中位尘埃盘质量与外部紫外场强度之间存在一种关系。本文利用盘演化模型探讨这一关系如何随时间以及相对于其他恒星和盘性质而演化。我们发现，随着族群年龄增长，关系斜率 λ_UV 随时间趋于平缓，这可能解释了猎户座 A 中 L1641-N 和 L1641-S 星团之间所见到的差异。我们确定 λ_UV 依赖于恒星质量，质量较大的恒星表现出比质量较小的对应天体更陡的梯度，这与 Herbig 星和 T Tauri 星之间所见到的差异一致。此外，角动量输运机制的强度，无论是粘滞还是磁流体动力学（MHD）盘风，被发现会显著影响 λ_UV，较强的 α 值会降低 λ_UV，因为在较弱的紫外环境中更多物质会吸积到中心恒星上。根据 L1641 的观测对 λ_UV 的估计对 α 施加了初步约束，使其介于 10^{-3.5} 至 10^{-2.5} 之间，与文献估计一致。在不同区域进行进一步观测以及对恒星质量进行更好的分类，将使我们能够对盘演化性质施加严格约束，从而增进我们对原行星盘如何演化的理解。

英文摘要：

FUV radiation from massive stars launch photoevaporative winds from the outer regions of protoplanetary discs around other stars, removing gas and dust. Observations have identified a relation between the median dust disc mass and the external UV field strength. Here we use disc evolutionary models to explore how this relation evolves over time, and with respect to other stellar and disc properties. We find that the slope for the relationship $λ_{\rm UV}$ flattens over time as populations age, possibly explaining the differences seen between the L1641-N and L1641-S clusters in Orion A. We determine that $λ_{\rm UV}$ depends on the stellar mass where more massive stars exhibit steeper gradients than their lesser counterparts, in agreement with the differences seen between Herbig and T Tauri stars. Additionally, the strength of the mechanism for angular momentum transport, either viscosity or MHD disc winds, is found to significantly affect $λ_{\rm UV}$ with stronger $α$ values reducing $λ_{\rm UV}$ due to more material accreting on to the central stars in weaker UV environments. Estimates of $λ_{\rm UV}$ from observations of L1641 place preliminary constraints on $α$ to be between $10^{-3.5}$--$10^{-2.5}$, consistent with literature estimates. Further observations in different regions and better classifications of stellar masses will allow us to place stringent constraints on disc evolution properties, improving our understanding of how protoplanetary discs evolve.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑