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arXiv 2408.03396astro-ph.GA
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从水母星系尾迹方向在光学波段约束冲压剥离特征持续时间

Constraining the duration of ram pressure stripping features in the optical from the direction of jellyfish galaxy tails

Vicente Salinas, Yara L. Jaffé, Rory Smith, Jong-Ho Shinn, Jacob P. Crossett, Marco Gullieuszik, Gemma González-Torà, Franco Piraino-Cerda, Bianca Poggianti, Be… 展开作者

Vicente Salinas, Yara L. Jaffé, Rory Smith, Jong-Ho Shinn, Jacob P. Crossett, Marco Gullieuszik, Gemma González-Torà, Franco Piraino-Cerda, Bianca Poggianti, Benedetta Vulcani, Andrea Biviano, Ana C. C. Lourenço, Lawrence E. Bilton, Kshitija Kelkar, Paula Calderón-Castillo

AI总结:

本文利用本地星系团中最大的均匀宽带光学水母星系样本,测量尾迹方向与星系团中心方向的夹角,并结合N体模拟和贝叶斯参数估计,揭示冲压剥离对径向落入星系的更强效应,并首次约束光学尾迹在约1.16 R200处出现、近心点后约660 Myr消失的寿命。

摘要:

当星系在致密环境中穿过星系际介质时,冲压剥离可能是移除气体并使星系淬灭的最高效机制。正在进行的冲压剥离的极端例子被称为水母星系,其特征是一条被剥离物质的尾迹,可以在多个波段直接观测到。利用迄今为止已知的本地星系团中最大的均匀宽带光学水母候选样本,我们测量了星系中可见尾迹的方向与指向宿主星系团中心方向之间的夹角。我们发现33%的星系尾迹指向远离星系团中心,18%指向星系团中心,49%指向其他方向。此外,我们发现尾迹指向远离和指向星系团中心的星系上存在更强的冲压剥离特征,而尾迹指向远离的星系具有更大的速度弥散剖面。这些结果与冲压剥离对首次落入时沿径向轨道运动的星系具有更强效应的图景一致。结果还表明,在许多情况下,径向落入的星系能够在经过近心点之后保留其尾迹,并继续经历显著的持续冲压剥离。我们进一步通过贝叶斯参数估计将观测到的尾迹方向与匹配的N体模拟进行比较,约束了光学尾迹从首次出现到消失的寿命。我们得到星系尾迹在约1.16 R$_{200}$处首次出现,并在近心点后约660 Myr消失。

英文摘要:

Ram pressure stripping is perhaps the most efficient mechanism for removing gas and quenching galaxies in dense environments as they move through the intergalactic medium. Extreme examples of on-going ram pressure stripping are known as jellyfish galaxies, characterized by a tail of stripped material that can be directly observed in multiple wavelengths. Using the largest homogeneous broad-band optical jellyfish candidate sample in local clusters known to date, we measure the angle between the direction of the tails visible in the galaxies, and the direction towards the host cluster center. We find that $33\%$ of the galaxy tails point away from the cluster center, $18\%$ point towards the cluster center, and $49\%$ point elsewhere. Moreover, we find stronger signatures of ram pressure stripping happening on galaxies with a tail pointing away and towards the cluster center, and larger velocity dispersion profiles for galaxies with tails pointing away. These results are consistent with a scenario where ram pressure stripping has a stronger effect for galaxies following radial orbits on first infall. The results also suggest that in many cases, radially infalling galaxies are able to retain their tails after pericenter and continue to experience significant on-going ram pressure stripping. We further constrain the lifespan of the optical tails from the moment they first appear to the moment they disappear, by comparing the observed tail directions with matched N-body simulations through Bayesian parameter estimation. We obtain that galaxy tails appear for the first time at $\sim 1.16$ R$_{200}$ and disappear $\sim660$ Myr after pericenter.

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。

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