COLD GASS，一项IRAM对大质量镓中分子气体的遗留调查：III。与星系形成半解析模型的比较
COLD GASS, an IRAM Legacy Survey of Molecular Gas in Massive Galaxies: III. Comparison with semi-analytic models of galaxy formation
摘要：
我们比较了Fu等人（2010）的星系形成的半解析模型，该模型跟踪了星系中原子和分子气体径向分布的演化，并与来自COLD GASS调查的气体分数标度关系（Saintonge等人，2011）进行了比较。该模型提供了一个很好的描述如何凝聚重子在星系与气体划分成恒星，原子和分子气体作为星系恒星质量和表面密度的函数。该模型不再现紧密观察到的恒星表面密度和膨胀盘比这个人口之间的关系。然后，我们转向分析的“淬火”人口的星系没有检测到的冷气体。目前实施的无线电模式反馈的模型不同意强烈的数据。在模型中，气体冷却在质量超过10**12 M_sun的暗物质晕中几乎所有星系中关闭。因此，恒星质量是最能预测星系是否有少量或根本没有中性气体的观测值。相比之下，我们的数据表明，淬火在很大程度上与恒星质量无关。相反，有明确的阀值在膨胀盘比和恒星表面密度，划分淬火星系的位置。我们建议，与隆起形成的过程中发挥了关键作用，在耗尽星系中的中性气体和进一步的气体吸积抑制隆起的形成后，即使在低质量的暗物质晕。
英文摘要：
We compare the semi-analytic models of galaxy formation of Fu et al. (2010), which track the evolution of the radial profiles of atomic and molecular gas in galaxies, with gas fraction scaling relations derived from the COLD GASS survey (Saintonge et al 2011). The models provide a good description of how condensed baryons in galaxies with gas are partitioned into stars, atomic and molecular gas as a function of galaxy stellar mass and surface density. The models do not reproduce the tight observed relation between stellar surface density and bulge-to-disk ratio for this population. We then turn to an analysis of the"quenched" population of galaxies without detectable cold gas. The current implementation of radio-mode feedback in the models disagrees strongly with the data. In the models, gas cooling shuts down in nearly all galaxies in dark matter halos above a mass of 10**12 M_sun. As a result, stellar mass is the observable that best predicts whether a galaxy has little or no neutral gas. In contrast, our data show that quenching is largely independent of stellar mass. Instead, there are clear thresholds in bulge-to-disk ratio and in stellar surface density that demarcate the location of quenched galaxies. We propose that processes associated with bulge formation play a key role in depleting the neutral gas in galaxies and that further gas accretion is suppressed following the formation of the bulge, even in dark matter halos of low mass.
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。
