发表机构
University of Sydney; University of Southern Queensland; University of Hawaii（悉尼大学; 昆士兰科技大学; 夏威夷大学）
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TESS数据对3200颗明亮δ Scuti星进行能量分析，发现积分功率谱密度呈双峰性并存在总脉动能量上限，揭示了两种脉动机制及受限的能量预算。
AI 中文摘要
δ Scuti星的脉动表现出广泛的激发频率和振幅范围，但控制其振幅分布的潜在原理仍不清楚。我们采用基于能量的全局视角重新审视这一问题。对于TESS观测到的3200颗明亮δ Scuti星的完整样本，傅里叶谱的积分功率谱密度（PSD）使我们能够测量整体脉动信号。由此，我们推导出总脉动能量的一个代理量。我们发现了高频δ Scuti星在积分PSD中的双峰性，这可能表明存在两种不同的脉动机制。此外，我们识别出总脉动能量存在一个明显的上限，表明这些脉动的能量预算受到约束。当仅以主模振幅来表征恒星时，这一特征并不明显。
英文摘要
Pulsations in $δ$ Scuti stars exhibit a wide range of excited frequencies and amplitudes, but the underlying principles governing their amplitude distribution remain unclear. We revisit this problem using a global, energy-based perspective. For a complete sample of 3200 bright $δ$ Scuti stars observed by TESS, integrated power spectral density (PSD) of the Fourier spectrum allows us to measure the overall pulsation signal. From this, we derive a proxy for the total pulsation energy. We uncover a bimodality among higher-frequency delta Scuti stars in their integrated PSD, possibly suggesting the presence of two distinct pulsation regimes. In addition, we identify an apparent upper limit to the total pulsation energy, indicating a constrained energy budget for these pulsations. This feature is not evident when stars are characterized solely by their dominant mode amplitude.
CommentsAccepted for publication in MNRAS
Journal refMonthly Notices of the Royal Astronomical Society (2026)
