Spatially resolved gas-phase metallicity in FIRE-2 dwarfs: late-time evolution of metallicity relations in simulations with feedback and mergers
Spatially resolved gas-phase metallicity in FIRE-2 dwarfs: late-time evolution of metallicity relations in simulations with feedback and mergers
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FIRE-2矮星中空间分辨的气相金属丰度：反馈和合并模拟中金属丰度关系的后期演化
DOI：
10.1093/mnras/stac1958
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发表时间：
2022
影响因子：
4.8
通讯作者：
Emerick, Andrew
中科院分区：
文献类型：
--
作者：
Porter, Lori E.;Orr, Matthew E.;Burkhart, Blakesley;Wetzel, Andrew;Ma, Xiangcheng;Hopkins, Philip F.;Emerick, Andrew
我们提出了一个空间分辨的气相金属丰度关系的分析，在五个矮星系（，）从消防2（反馈在现实环境中）宇宙放大模拟套件，其中包括一个明确的模型，亚网格湍流混合气体中的金属，近z = 0，超过1.4 Gyr的一段时间，并比较我们的研究结果与观测。虽然这些矮星系代表了不同的样本，但我们发现所有模拟星系都与观测到的质量-金属丰度（MZR）和质量-金属丰度梯度（MZGR）关系相匹配。我们注意到，在所有五个星系中，星际介质（ISM）的相位之间的金属丰度实际上是相同的，其中95的气体在冷致密气体（T < 500 K andnH>1 cm−3）、电离气体（靠近H αT <$104 K山脊线）和星云区域（电离气体，1千万年平均星星形成率不为零）之间的±0.1 dex之内。我们发现，大部分的相对金属丰度冷致密气体和电离气体/星云区域之间的分散可以归因于本地星暴事件或金属贫流入。我们还注意到，在我们的星系之一，m11 e的主要合并的存在下，在空间分辨地图的金属丰度分布的重大影响，显示出两个强大的金属丰度峰值，并触发在主星系的星暴。
We present an analysis of spatially resolved gas-phase metallicity relations in five dwarf galaxies (,) from the FIRE-2 (Feedback in Realistic Environments) cosmological zoom-in simulation suite, which include an explicit model for sub-grid turbulent mixing of metals in gas, nearz≈ 0, over a period of 1.4 Gyr, and compare our findings with observations. While these dwarf galaxies represent a diverse sample, we find that all simulated galaxies match the observed mass–metallicity (MZR) and mass–metallicity gradient (MZGR) relations. We note that in all five galaxies, the metallicities are effectively identical between phases of the interstellar medium (ISM), with 95of the gas being within ±0.1 dex between the cold and dense gas (T< 500 K andnH> 1 cm−3), ionized gas (near the H αT≈ 104K ridge-line), and nebular regions (ionized gas where the 10 Myr-averaged star formation rate is non-zero). We find that most of the scatter in relative metallicity between cold dense gas and ionized gas/nebular regions can be attributed to either local starburst events or metal-poor inflows. We also note the presence of a major merger in one of our galaxies,m11e, with a substantial impact on the metallicity distribution in the spatially resolved map, showing two strong metallicity peaks and triggering a starburst in the main galaxy.