Infrared Emission from the Nearby Cool Core Cluster Abell 2597
Infrared Emission from the Nearby Cool Core Cluster Abell 2597
复制标题
附近冷核心星团 Abell 2597 发射的红外光
DOI：
10.1086/522575
复制
发表时间：
2007
期刊：
影响因子：
--
通讯作者：
G. Voit
中科院分区：
文献类型：
--
作者：
M. Donahue;A. Jordán;S. Baum;P. Côté;L. Ferrarese;P. Goudfrooij;D. Macchetto;S. Malhotra;C. O’Dea;J. E. Pringle;J. Rhoads;W. Sparks;G. Voit
我们用斯皮策太空望远镜上的IRAC和MIPS仪器观测了附近（z = 0.0821）冷核星系团阿贝尔2597中最亮的中央星系（BCG）。BCG在Spitzer的70和160 μm波段都能被清晰地检测到。本文报道了BCG的孔径测光。光谱能量分布在瑞利-金斯星尾的远红外区有明显的过剩，表明星星的形成速率为4-5兆年-1，与紫外线和Hα光度的估计一致。这个巨大的远红外光度与星暴或明亮的红外星系一致，但同时还有一个非常巨大和古老的恒星群体，主导着星系的能量输出。如果尘埃处于一个温度，70和160 μm的通量之比表明，这个源中发射中红外的尘埃比斯皮策在阿贝尔1835和兹维基3146中观测到的两个具有较高红移（z ~ 0.2-0.3）和较高远红外光度的BCGs中发射中红外的尘埃要热一些。
We observed the brightest central galaxy (BCG) in the nearby (z = 0.0821) cool core galaxy cluster Abell 2597 with the IRAC and MIPS instruments on board the Spitzer Space Telescope. The BCG was clearly detected in all Spitzer bandpasses, including the 70 and 160 μm wave bands. We report aperture photometry of the BCG. The spectral energy distribution exhibits a clear excess in the far-IR over a Rayleigh-Jeans stellar tail, indicating a star formation rate of ~4-5 M☉ yr-1, consistent with the estimates from the UV and its Hα luminosity. This large far-IR luminosity is consistent with that of a starburst or a luminous infrared galaxy, but together with a very massive and old population of stars that dominate the energy output of the galaxy. If the dust is at one temperature, the ratio of 70 to 160 μm fluxes indicates that the dust emitting mid-IR in this source is somewhat hotter than the dust emitting mid-IR in two BCGs at higher redshift (z ~ 0.2-0.3) and higher far-IR luminosities observed earlier by Spitzer in clusters Abell 1835 and Zwicky 3146.