Predicting a Single-Temperature Fit to Multicomponent Thermal Plasma Spectra
Predicting a Single-Temperature Fit to Multicomponent Thermal Plasma Spectra
复制标题
预测多组分热等离子体光谱的单温度拟合
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
A. Vikhlinin
中科院分区：
文献类型：
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作者：
A. Vikhlinin
在星系团、星系群和单个星系中观测到的热气体的X射线光谱通常符合单温热等离子体模型，尽管光束可能包含不同温度成分的发射。最近，Mazzotta等人。指出这样导出的TSPEC可能与通常使用的平均温度定义(如发射加权或发射测量加权T)有很大不同，并找到了预测具有相对较热温度(T≳3keV)的等离子体光谱混合物的TSPEC的解析表达式。在本文中，我们提出了一种算法，它可以在更宽的温度范围内(T≳0.5keV)准确地预测TSPEC，并且基本上可以预测任意丰度的重元素。该算法可用于具有温度和金属丰度梯度的天体的去投影分析，用于校正点扩展函数(PSF)效应，用于星系团和星系团的数值模拟与X射线观测的一致性比较，以及用于估计来自未探测到的分量的发射如何影响全球X射线光谱分析。
Observed X-ray spectra of hot gas in clusters, groups, and individual galaxies are commonly fit with a single-temperature thermal plasma model, although the beam may contain emission from components with different temperatures. Recently, Mazzotta et al. pointed out that thus derived Tspec can be significantly different from commonly used definitions of average temperature, such as emission-weighted or emission measure-weighted T, and found an analytic expression for predicting Tspec for a mixture of plasma spectra with relatively hot temperatures (T ≳ 3 keV). In this paper, we propose an algorithm that can accurately predict Tspec in a much wider range of temperatures (T ≳ 0.5 keV) and for essentially arbitrary abundances of heavy elements. This algorithm can be applied in the deprojection analysis of objects with the temperature and metallicity gradients, for correction of the point-spread function (PSF) effects, for consistent comparison of numerical simulations of galaxy clusters and groups with the X-ray observations, and for estimating how emission from undetected components can bias the global X-ray spectral analysis.