Feedback first: the surprisingly weak effects of magnetic fields, viscosity, conduction and metal diffusion on sub-L* galaxy formation
Feedback first: the surprisingly weak effects of magnetic fields, viscosity, conduction and metal diffusion on sub-L* galaxy formation
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首先反馈：磁场、粘度、传导和金属扩散对亚 L* 星系形成的影响令人惊讶地微弱
DOI：
10.1093/mnras/stx1463
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发表时间：
2017
影响因子：
4.8
通讯作者：
Robles, Victor H.
中科院分区：
文献类型：
--
作者：
Su, Kung-Yi;Hopkins, Philip F.;Hayward, Christopher C.;Faucher-Giguère, Claude-André;Kereš, Dušan;Ma, Xiangcheng;Robles, Victor H.
利用基于FIRE （feedback In Realistic Environments）项目的高分辨率模拟和明确的恒星反馈物理处理，我们研究了星系形成和星际介质（ISM）如何受到磁场、各向异性斯皮策-布拉金斯基传导和粘度以及未解决湍流的亚网格金属扩散的影响。我们考虑孤立（非宇宙学）星系的控制模拟，但也考虑一组有限的宇宙学“放大”模拟。虽然模拟已经显示了这些物理现象在微弱或不存在恒星反馈的情况下产生的显著影响，但当后者被明确建模时，其影响要比恒星反馈的影响弱得多。附加的物理对星系恒星形成速率（SFRs）没有系统的影响。相反，去除恒星反馈会导致sfr被高估约10-100倍。没有反馈，星系风和充满体积的热相气体都不存在，星系盘倾向于失控地坍缩成超薄的尺度高度，在星系中心聚集着非物理上稠密的团块。利用恒星反馈，建立了具有星系喷泉和风的多相湍流介质。在目前可实现的分辨率和所研究的光晕质量范围1010-1013M⊙下，这里研究的附加物理（磁流体动力学、传导、粘度、金属扩散）对调节SFR和改变相平衡、流出物或ISM湍流中的能量只有微弱（~ 10%水平）的影响，与简单的均分论点一致。我们得出的结论是，银河系恒星的形成和ISM主要是由湍流、引力不稳定性和反馈的组合控制的。我们补充说，活动星系核反馈不包括在目前的工作中。
Using high-resolution simulations with explicit treatment of stellar feedback physics based on the FIRE (Feedback In Realistic Environments) project, we study how galaxy formation and the interstellar medium (ISM) are affected by magnetic fields, anisotropic Spitzer–Braginskii conduction and viscosity, and sub-grid metal diffusion from unresolved turbulence. We consider controlled simulations of isolated (non-cosmological) galaxies but also a limited set of cosmological ‘zoom-in’ simulations. Although simulations have shown significant effects from these physics with weak or absent stellar feedback, the effects are much weaker than those of stellar feedback when the latter is modelled explicitly. The additional physics have no systematic effect on galactic star formation rates (SFRs). In contrast, removing stellar feedback leads to SFRs being overpredicted by factors of ∼10–100. Without feedback, neither galactic winds nor volume-filling hot-phase gas exist, and discs tend to runaway collapse to ultra-thin scaleheights with unphysically dense clumps congregating at the galactic centre. With stellar feedback, a multi-phase, turbulent medium with galactic fountains and winds is established. At currently achievable resolutions and for the investigated halo mass range 1010–1013M⊙, the additional physics investigated here (magnetohydrodynamic, conduction, viscosity, metal diffusion) have only weak (∼10 per cent-level) effects on regulating SFR and altering the balance of phases, outflows or the energy in ISM turbulence, consistent with simple equipartition arguments. We conclude that galactic star formation and the ISM are primarily governed by a combination of turbulence, gravitational instabilities and feedback. We add the caveat that active galactic nucleus feedback is not included in the present work.
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ISM 中热不稳定和磁旋转不稳定造成的饱和态湍流和结构：三维数值模拟
DOI：
10.1086/431549
发表时间：
2005
期刊：
The Astrophysical Journal
影响因子：
--
作者：
R. Piontek;E. Ostriker
通讯作者：
E. Ostriker
局部垂直分层介质中的超新星反馈：星际湍流和银河风
DOI：
--
发表时间：
2016
期刊：
影响因子：
--
作者：
D. Martizzi;D. Fielding;C. Faucher;E. Quataert
通讯作者：
E. Quataert
DOI：
10.1111/j.1365-2966.2011.19306.x
发表时间：
2011-01
影响因子：
4.8
作者：
P. Hopkins;E. Quataert;N. M. Berkeley;Cita
通讯作者：
P. Hopkins;E. Quataert;N. M. Berkeley;Cita
解决星系合并中星暴风的产生问题
影响因子：
4.8
作者：
Haverford Scholarship;P. Hopkins;D. Keres̆;N. Murray;L. Hernquist;D. Narayanan;P. Hopkins;D. Keres̆;N. Murray;L. Hernquist;Christopher C. Hayward
通讯作者：
Christopher C. Hayward
模拟银河系质量星系星盘的结构和动力学演化
影响因子：
4.8
作者：
Ma, Xiangcheng;Hopkins, Philip F.;Wetzel, Andrew R.;Kirby, Evan N.;Anglés-Alcázar, Daniel;Faucher-Giguère, Claude-André;Kereš, Dušan;Quataert, Eliot
通讯作者：
Quataert, Eliot