AGN host galaxy mass function in COSMOS: is AGN feedback responsible for the mass-quenching of galaxies?
AGN host galaxy mass function in COSMOS: is AGN feedback responsible for the mass-quenching of galaxies?
复制标题
COSMOS 中 AGN 宿主星系质量函数：AGN 反馈是否对星系的质量猝灭负责？
DOI：
10.1051/0004-6361/201527436
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
N. Scoville
中科院分区：
文献类型：
--
作者：
A. Bongiorno;A. Schulze;A. Merloni;G. Zamorani;O. Ilbert;F. Franca;Yingjie Peng;E. Piconcelli;V. Mainieri;J. Silverman;M. Brusa;M. Brusa;F. Fiore;M. Salvato;N. Scoville
我们通过测量宿主星系的恒星质量函数（HGMF）和特定的吸积率，即，λ_SAR，分布函数（SARDF），z~2.5与~1000 X射线从XMM-COSMOS选择AGN。使用最大似然法，我们共同拟合恒星质量函数和特定的吸积率分布函数，与X射线光度函数作为一个额外的约束。我们的最佳拟合模型将SARDF描述为具有质量依赖但与红移无关的双幂律破缺，其低Lambda_SAR斜率随着红移的增加而增加，同时归一化增加。这意味着，对于一个给定的恒星质量，较高的lambda_SAR对象有一个峰值，在其空间密度在较早的时代相比，较低的lambda_SAR的，以下和模仿众所周知的AGN宇宙缩小AGN光度函数中观察到的。活动星系的质量函数用Schechter函数来描述，它具有几乎恒定的Mstar* 和低的质量斜率α，α随红移而变化。通过与恒星质量函数的比较，我们发现HGMF具有相似的形状，并且在log（（M星星/Msun）~11.5范围内，活动星系核的宿主星系与形成星星的星系之比基本保持不变（~10%）。最后，不同光度和比吸积率子类的活动星系核HGMF与Peng等人（2010）对“瞬态”群体（即处于质量猝灭过程中的星系）的唯象模型预测的比较表明，低光度活动星系核似乎不能对猝灭做出显着贡献，至少在高质量时，即M星星>10^（10.7）Msun，来自活动星系核的反馈（log（Lbol）>~46 [erg/s]）可能是导致宿主星系中星星形成猝灭的原因。
We investigate the role of supermassive black holes in the global context of galaxy evolution by measuring the host galaxy stellar mass function (HGMF) and the specific accretion rate i.e., lambda_SAR, distribution function (SARDF) up to z~2.5 with ~1000 X-ray selected AGN from XMM-COSMOS. Using a maximum likelihood approach, we jointly fit the stellar mass function and specific accretion rate distribution function, with the X-ray luminosity function as an additional constraint. Our best fit model characterizes the SARDF as a double power-law with mass dependent but redshift independent break whose low lambda_SAR slope flattens with increasing redshift while the normalization increases. This implies that, for a given stellar mass, higher lambda_SAR objects have a peak in their space density at earlier epoch compared to the lower lambda_SAR ones, following and mimicking the well known AGN cosmic downsizing as observed in the AGN luminosity function. The mass function of active galaxies is described by a Schechter function with a almost constant Mstar* and a low mass slope alpha that flattens with redshift. Compared to the stellar mass function, we find that the HGMF has a similar shape and that, up to log((Mstar/Msun)~11.5 the ratio of AGN host galaxies to star forming galaxies is basically constant (~10%). Finally, the comparison of the AGN HGMF for different luminosity and specific accretion rate sub-classes with the phenomenological model prediction by Peng et al. (2010) for the "transient" population, i.e. galaxies in the process of being mass-quenched, reveals that low-luminosity AGN do not appear to be able to contribute significantly to the quenching and that at least at high masses, i.e. Mstar>10^(10.7) Msun , feedback from luminous AGN (log(Lbol)>~46 [erg/s]) may be responsible for the quenching of star formation in the host galaxy.
影响因子：
6.5
作者：
A. Schulze;L. Wisotzki
通讯作者：
A. Schulze;L. Wisotzki