Intracluster and Intragroup Entropy from Quasar Activity
Intracluster and Intragroup Entropy from Quasar Activity
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DOI：
10.1086/426376
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发表时间：
2004-10
期刊：
影响因子：
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通讯作者：
A. Lapi;A. Cavaliere;N. Menci
中科院分区：
文献类型：
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作者：
A. Lapi;A. Cavaliere;N. Menci
我们研究暗物质晕的分层合并、重子的辐射冷却以及来自超新星和活动星系核或类星体的能量反馈如何结合起来控制弥漫在星系团和星系团中的热等离子体的数量和热状态。我们表明，流入星团的外部气体的超新星预热本身不足以解释观测到的等离子体光度 LX 或等离子体熵 K 与 X 射线温度 T 的 X 射线标度关系。为了解释从富星团到贫星团的标度定律，需要通过活动星系核的能量输入来增强预热。另一方面，在星系群中，成员星系中爆发的强大类星体的内部撞击可能会将一些等离子体吹出结构。因此，他们降低 LX 并将 K 提高到观察到的平均水平；同时，此类脉冲事件的零星性质产生了数据中明显的广泛分散的内在成分。相同的类星体反馈会在群体中产生与观察到的一样陡峭的熵剖面，这一特征很难用简单的预热方案来解释。最后，我们论证了 LX-T 或 K-T 关系与宿主速度色散和类星体活动遗迹黑洞质量之间的 M•-σ 相关性之间的密切联系。
We investigate how the hierarchical merging of dark matter halos, the radiative cooling of baryons, and the energy feedback from supernovae and active galactic nuclei or quasars combine to govern the amount and the thermal state of the hot plasma pervading groups and clusters of galaxies. We show that, by itself, supernova preheating of the external gas flowing into clusters falls short of explaining the observed X-ray scaling relations of the plasma luminosity LX or the plasma entropy K versus the X-ray temperature T. To account for the scaling laws from rich to poor clusters takes preheating enhanced by the energy input from active galactic nuclei. In groups, on the other hand, the internal impacts of powerful quasars going off in member galaxies can blow some plasma out of the structure. So they depress LX and raise K to the observed average levels; meanwhile, the sporadic nature of such impulsive events generates the intrinsic component of the wide scatter apparent in the data. The same quasar feedback gives rise in groups to entropy profiles as steep as observed, a feature hard to explain with simple preheating schemes. Finally, we argue a close connection of the LX-T or the K-T relation with the M•-σ correlation between the host velocity dispersion and the masses of the black holes, relics of the quasar activity.