2-10 KeV luminosity of high - mass binaries as a gauge of ongoing star - formation rate
2-10 KeV luminosity of high - mass binaries as a gauge of ongoing star - formation rate
复制标题
高质量双星的2-10 KeV光度作为正在进行的恒星形成速率的衡量标准
DOI：
10.1051/0004-6361:20034500
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发表时间：
2004
影响因子：
6.5
通讯作者：
D. Gruber
中科院分区：
文献类型：
--
作者：
M. Persic;Y. Rephaeli;Y. Rephaeli;V. Braito;M. Cappi;R. Ceca;A. Franceschini;D. Gruber
基于最近对恒星形成星系发射光谱分解的研究，我们评估了高质量x射线双星（HMXB）的综合2−10 keV发射（L HMXB−10）是否可以作为正在进行的恒星形成速率（SFR）的可靠估计。利用46个局部（z < 0.1）恒星形成星系的样本，以及ASCA， BeppoSAX和XMM-Newton数据的光谱建模，我们证明了线性SFR -L HMXB−10关系的存在，该关系在x射线光度和SFR中保持了~ 50年。总2−10 keV光度不是精确的SFR指标，因为在低SFR（即在正常和中等恒星爆发星系中），它基本上受到低质量x射线双星发射的影响，由于它们的长演化寿命，它们不能追踪当前的SFR，而在非常高的SFR（即对于非常明亮的fir选择的星系），它经常受到强烈遮挡的agn存在的影响。纯sb驱动的星系（其2−10 keV发射主要是由于HMXB）的可用性使我们能够正确校准SFR - l HMXB−10关系。SFR -L HMXB−10关系也适用于哈勃深场北部样本中遥远的（z ~ 1）星系，我们缺乏光谱信息，但其SFR可以从深射电数据中估计出来。如果得到更详细的观测结果的证实，就有可能利用推导出的关系来识别那些因其（独立估计的）SFR而x射线过亮的遥远星系，因此可能隐藏了被强烈吸收的agn。
Based on recent work on spectral decomposition of the emission of star-forming galaxies, we assess whether the inte- grated 2−10 keV emission from high-mass X-ray binaries (HMXBs), L HMXB−10 , can be used as a reliable estimator of ongoing star formation rate (SFR). Using a sample of 46 local (z < 0.1) star-forming galaxies, and spectral modeling of ASCA, BeppoSAX, and XMM-Newton data, we demonstrate the existence of a linear SFR -L HMXB−10 relation which holds over ∼5 decades in X-ray luminosity and SFR. The total 2−10 keV luminosity is not a precise SFR indicator because at low SFR (i.e., in normal and moderately-starbursting galaxies) it is substantially affected by the emission of low-mass X-ray binaries, which do not trace the current SFR due to their long evolution lifetimes, while at very high SFR (i.e., for very luminous FIR-selected galaxies) it is frequently affected by the presence of strongly obscured AGNs. The availability of purely SB-powered galaxies - whose 2−10 keV emission is mainly due to HMXBs - allows us to properly calibrate the SFR -L HMXB−10 relation. The SFR -L HMXB−10 relation holds also for distant (z ∼ 1) galaxies in the Hubble Deep Field North sample, for which we lack spectral information, but whose SFR can be estimated from deep radio data. If confirmed by more detailed observations, it may be possible to use the deduced relation to identify distant galaxies that are X-ray overluminous for their (independently estimated) SFR ,a nd are therefore likely to hide strongly absorbed AGNs.