Evolutionary synthesis of galaxies at high spectral resolution with the code PEGASE-HR. Metallicity and age tracers
Evolutionary synthesis of galaxies at high spectral resolution with the code PEGASE-HR. Metallicity and age tracers
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DOI：
10.1051/0004-6361:200400044
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发表时间：
2004-08
影响因子：
6.5
通讯作者：
D. L. Borgne;B. Rocca-Volmerange;P. Prugniel;A. Lançon;M. Fioc;Caroline Soubiran Institut d'Astrophysique de Paris;U. Toronto;crAl;O. Strasbourg;O. Bordeaux
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作者：
D. L. Borgne;B. Rocca-Volmerange;P. Prugniel;A. Lançon;M. Fioc;Caroline Soubiran Institut d'Astrophysique de Paris;U. Toronto;crAl;O. Strasbourg;O. Bordeaux
我们介绍了PEGASE - HR，这是一个新的恒星族合成程序，它能在光学波段λλ = 400 - 680nm范围内生成高分辨率光谱（R = 10000）。它将星系演化的分光光度模型PEGASE.2（菲奥克和罗卡 - 沃尔默朗热，1997年）与上普罗旺斯天文台193厘米望远镜观测到的恒星光谱ELODIE库的更新版本相联系（普鲁尼埃尔和苏比兰，2001a）。ELODIE恒星集相当完整地覆盖了赫茨普龙 - 罗素（HR）图，使得在（铁/氢）= - 2到 + 0.4范围内合成恒星族成为可能。这个程序是探索金属丰度、年龄和运动学特征的绝佳工具。我们重点详细研究了高分辨率恒星吸收线以及迄今为止为解决年龄 - 金属丰度简并性而提出的经典金属指数对年龄和金属丰度的敏感度。通过将我们对里克指数的预测与其他团队的模型进行比较，对几条恒星线进行了有效性测试。与低分辨率的BaSeL库（勒热纳等人，1997年）的比较证实了ELODIE库在用于10⁷到2×10¹⁰年的单恒星族（SSPs）时的质量。给出了球状星团和椭圆星系演化恒星族的预测，并与观测数据进行了比较。在Hγ线附近提出了两个新的高分辨率指数。它们应该在分析新一代望远镜和光谱仪的光谱时被证明是有用的。
We present PEGASE-HR, a new stellar population synthesis program generating high resolution spectra (R = 10 000) over the optical range λλ = 400-680 nm. It links the spectro-photometric model of galaxy evolution PEGASE.2 (Fioc & Rocca-Volmerange 1997) to an updated version of the ELODIE library of stellar spectra observed with the 193 cm telescope at the Observatoire de Haute-Provence (Prugniel & Soubiran 2001a). The ELODIE star set gives a fairly complete coverage of the Hertzprung-Russell (HR) diagram and makes it possible to synthesize populations in the range (Fe/H) = − 2t o+0.4. This code is an exceptional tool for exploring signatures of metallicity, age, and kinematics. We focus on a detailed study of the sensitivity to age and metallicity of the high-resolution stellar absorption lines and of the classical metallic indices proposed until now to solve the age-metallicity degeneracy. Validity tests on several stellar lines are performed by comparing our predictions for Lick indices to the models of other groups. The comparison with the lower resolution library BaSeL (Lejeune et al. 1997) confirms the quality of the ELODIE library when used for single stellar populations (SSPs) from 10 7 to 2 × 10 10 yr. Predictions for the evolved populations of globular clusters and elliptical galaxies are given and compared to observational data. Two new high- resolution indices are proposed around the Hγ line. They should prove useful in the analysis of spectra from the new generation of telescopes and spectrographs.