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arXiv 2110.04537astro-ph.GA
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TNG50模拟中棒星系群体的演化

The evolution of the barred galaxy population in the TNG50 simulation

Yetli Rosas-Guevara, Silvia Bonoli, Massimo Dotti, David Izquierdo-Villalba, Alessandro Lupi, Tommaso Zana, Matteo Bonetti, Dylan Nelson, Volker Springel, Lars … 展开作者

Yetli Rosas-Guevara, Silvia Bonoli, Massimo Dotti, David Izquierdo-Villalba, Alessandro Lupi, Tommaso Zana, Matteo Bonetti, Dylan Nelson, Volker Springel, Lars Hernquist, Mark Vogelsberger

摘要:

利用磁流体动力学模拟TNG 50研究了棒斑盘星系的演化。早在$z=4$的时候就已经有大质量的螺旋星系存在,而棒的形成也在那个早期就已经发生了。随着宿主星系的演化,棒变得更长更强,棒的大小以类似于盘尺度长度的速度增加。对于具有$M_{*}\geq10^{10}M\odot$的星系,棒分数随着红移温和地演化,在$0.5<z<3$处大于$\sim40\%$,在$z=0$处大于$\sim30\%$。当考虑大于给定物理尺寸($\geq 2\,\rm kpc$)或角分辨率限制为HST I波段角点扩展函数FWHM的两倍的棒时,棒分数随着红移的增加而显著减小,使理论预测与观测数据相一致。我们发现,棒星系有一个老年人的恒星人口,较低的气体分数和恒星形成率比unbarred星系。在大多数情况下,棒星系的盘比无棒星系的盘组装得更早更快。我们还发现,棒星系是典型的晕较大的浓度和较小的自旋参数比unbarred星系。此外,有棒星系的内部区域比无棒星系更以重子为主,但具有可比的整体恒星质量分数。我们的研究结果表明,酒吧人口可以作为一个潜在的示踪剂的盘星系和他们的主机晕的建设。利用这篇论文,我们公布了TNG 50中$6$红移在$z=4$和$z=0$之间的棒星系目录。

英文摘要:

We use the magnetic-hydrodynamical simulation TNG50 to study the evolution of barred massive disc galaxies. Massive spiral galaxies are already present as early as $z=4$, and bar formation takes place already at those early times. The bars grow longer and stronger as the host galaxies evolve, with the bar sizes increasing at a pace similar to that of the disc scale lengths. The bar fraction mildly evolves with redshift for galaxies with $M_{*}\geq10^{10}M\odot$, being greater than $\sim40\%$ at $0.5<z<3$ and $\sim30\%$ at $z=0$. When bars larger than a given physical size ($\geq 2\,\rm kpc$) or the angular resolution limit of twice the I-band angular PSF FWHM of the HST are considered, the bar fraction dramatically decreases with increasing redshift, reconciling the theoretical predictions with observational data. We find that barred galaxies have an older stellar population, lower gas fractions and star formation rates than unbarred galaxies. In most cases, the discs of barred galaxies assembled earlier and faster than the discs of unbarred galaxies. We also find that barred galaxies are typical in haloes with larger concentrations and smaller spin parameters than unbarred galaxies. Furthermore, the inner regions of barred galaxies are more baryon-dominated than those of unbarred galaxies but have comparable global stellar mass fractions. Our findings suggest that the bar population could be used as a potential tracer of the buildup of disc galaxies and their host haloes. With this paper, we release a catalogue of barred galaxies in TNG50 at $6$ redshifts between $z=4$ and $z=0$.

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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