A standard stellar library for evolutionary synthesis: I. calibration of theoretical spectra
A standard stellar library for evolutionary synthesis: I. calibration of theoretical spectra
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DOI：
10.1051/aas:1997373
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发表时间：
1997-01
期刊：
影响因子：
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通讯作者：
T. Lejeune;F. Cuisinier;R. Inst.;U. Basel;CH Obs. Astron.;Strasbourg;FR Ins. Astron. e Geof.
中科院分区：
文献类型：
--
作者：
T. Lejeune;F. Cuisinier;R. Inst.;U. Basel;CH Obs. Astron.;Strasbourg;FR Ins. Astron. e Geof.
我们在Kurucz（1995）、Fluks等人（1994）和Bessell等人（1989、1991）的模型大气光谱的三个原始网格的基础上，提出了一个综合的混合恒星光谱库。该组合库是根据Buser和Kurucz（1992）采用的原则构建的，用于多种用途的合成光度测定应用：(i)覆盖尽可能大的恒星参数范围（Te,l og g，a和（M=H））；（ii）在Kurucz（1995）采用的波长均匀网格上提供有用分辨率的通量谱；（iii）提供合成宽频带颜色，这对于最大可能的参数和波长范围是高度真实的。由于与天体物理最相关的步骤是建立一个真实的库，因此对相应的颜色校准进行了一些详细的描述。基本上，对于每个有效温度值和每个波长，我们计算必须应用于（理论）太阳{丰度模型通量谱的校正函数，以便产生与观测得出的（经验）色{温度校准相匹配的合成UBVRIJHKL颜色。这样，原始模式光谱与观测之间存在的最重要的系统差异确实可以消除。另一方面，从原始的巨矮星模型光谱中得到的合成UBV和Washington紫外超量（U B）、（C M）和（C T1）与经验金属丰度校准非常吻合（Lejeune & Buser 1996）。因此，如果给定有效温度的太阳丰度模型的上述耦合函数也适用于相同温度但不同化学成分（M=H）和/或表面重力对数的模型，则校准算法的设计方式将保留新库中金属丰度和/或光度变化所隐含的原始微分网格特性。发送打印请求到：R。虽然新库构成了上面列出的程序的一级近似，但它将被允许朝着更雄心勃勃的目标发展，以满足标准库的全部要求。目前正在对球状星团（Lejeune 1997）和星系（Bruzual et al. 1997）的综合光进行的人口和进化综合研究进行广泛的测试，预计将为修订和完善提供重要的投入。
We present a comprehensive hybrid library of synthetic stellar spectra based on three original grids of model atmosphere spectra by Kurucz (1995), Fluks et al. (1994), and Bessell et al. (1989, 1991), respectively. The combined library has been intended for multiple-purpose synthetic photometry applications and was constructed according to the precepts adopted by Buser & Kurucz (1992): (i) to cover the largest possible ranges in stellar parameters (Te ,l og g ,a nd (M=H)); (ii) to provide flux spectra with useful resolution on the uniform grid of wave- lengths adopted by Kurucz (1995); and (iii) to provide synthetic broad{band colors which are highly realistic for the largest possible parameter and wavelength ranges. Because the most astrophysically relevant step consists in establishing a realistic library, the corresponding color calibration is described in some detail. Basically, for each value of the eective temperature and for each wavelength, we calculate the correction function that must be applied to a (theoretical) solar{abundance model flux spectrum in order for this to yield synthetic UBVRIJHKL colors matching the (empirical) color{temperature calibrations derived from observations. In this way, the most important systematic dierences existing between the original model spectra and the observations can indeed be eliminated. On the other hand, synthetic UBV and Washington ultravio- let excesses(U B) and(C M) and(C T1) obtained from the original giant and dwarf model spectra are in excel- lent accord with empirical metal{abundance calibrations (Lejeune & Buser 1996). Therefore, the calibration algo- rithm is designed in such a way as to preserve the original dierential grid properties implied by metallicity and/or luminosity changes in the new library, if the above cor- rection function for a solar{abundance model of a given eective temperature is also applied to models of the same temperature but dierent chemical compositions (M=H) and/or surface gravities logg. Send oprint requests to :R. Buser While the new library constitutes a rst{order approx- imation to the program set out above, it will be allowed to develop toward the more ambitious goal of matching the full requirements imposed on a standard library .M ajor input for renement and completion is expected from the extensive tests now being made in population and evolu- tionary synthesis studies of the integrated light of globular clusters (Lejeune 1997) and galaxies (Bruzual et al. 1997).