The ESO-Sculptor Survey: Luminosity functions of galaxies per spectral type at redshifts 0.1-0.5
The ESO-Sculptor Survey: Luminosity functions of galaxies per spectral type at redshifts 0.1-0.5
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ESO-Sculptor 巡天：红移 0.1-0.5 时每种光谱类型星系的光度函数
DOI：
10.1051/0004-6361:20030451
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发表时间：
2003
影响因子：
6.5
通讯作者：
Laboratoire d'Astrophysique de Marseille
中科院分区：
文献类型：
--
作者：
V. Lapparent;G. Galaz;S. Bardelli;Stephane Charlot Institut d'Astrophysique de Paris;P. Catolica;Santiago;I. A. Bologna;Laboratoire d'Astrophysique de Marseille
我们给出了对暗星系的完整的ESO-Sculptor调查(ESS)的第一次统计分析。基于主成分分析，将RC20：5的617个星系的通量校准样本分成3个光谱类别，从而提供了一个连续的、与模板无关的光谱分类。我们使用一种原始的方法来估计准确的K校正：使用主成分分析将ESS光谱与光谱库进行比较，使我们能够在蓝色波长外推观测光谱的缺失部分，然后提供作为光谱类型和红移的函数的K校正的多项式参数。我们还报告了影响光谱分类、K校正和由此产生的绝对震级的所有随机和系统误差的来源。我们使用绝对星等来测量ESS的Johnson-Cousins B，V，RC光度函数作为光谱类别的函数。得到的光度函数的形状在B、V、RC波段共有的三个光谱类别之间表现出明显的差异，因此反映了一个物理现象：对于较晚光谱类型的星系，特征星等较暗，而暗端较陡。ESS还提供了V波段中每种光谱类型的光度函数的第一次估计。显著的结果是通过将ESS光度函数与基于Sandage等人在当地测量的每种形态类型的Intrin光度函数的复合函数进行拟合而获得的。(1985)和Jerjen&Tammann(1997)。附近旋涡星系的高斯光度函数可以与ESS中间型和晚期光度函数相协调，如果相应的类分别包含来自球状和不规则矮星系的额外谢克特贡献。本文对ESS光度函数的分析是从红移观测对星系光度函数的重新解释。它还说明了形态类型混合如何影响每种光谱类型的光度函数，并强调了在z>；0：1处进行定量形态分类的必要性。
We present the first statistical analysis of the complete ESO-Sculptor Survey (ESS) of faint galaxies. The flux- calibrated sample of 617 galaxies with Rc 20:5 is separated into 3 spectral classes, based on a principal component analysis which provides a continuous and template-independent spectral classification. We use an original method to estimate accurate K-corrections: comparison of the ESS spectra with a spectral library using the principal component analysis allows us to extrapolate the missing parts of the observed spectra at blue wavelengths, then providing a polynomial parameterization of K-corrections as a function of spectral type and redshift. We also report on all sources of random and systematic errors which aect the spectral classification, the K-corrections, and the resulting absolute magnitudes. We use the absolute magnitudes to measure the Johnson-Cousins B, V, Rc luminosity functions of the ESS as a function of spectral class. The shape of the derived luminosity functions show marked dierences among the 3 spectral classes, which are common to the B, V, Rc bands, and therefore reflect a physical phenomenon: for galaxies of later spectral type, the characteristic magnitude is fainter and the faint-end is steeper. The ESS also provides the first estimates of luminosity functions per spectral type in the V band. The salient results are obtained by fitting the ESS luminosity functions with composite functions based on the intrin- sic luminosity functions per morphological type measured locally by Sandage et al. (1985) and Jerjen & Tammann (1997). The Gaussian luminosity functions for the nearby Spiral galaxies can be reconciled with the ESS intermediate and late-type luminosity functions if the corresponding classes contain an additional Schechter contribution from Spheroidal and Irregular dwarf galaxies, respectively. The present analysis of the ESS luminosity functions oers a renewed interpretation of the galaxy luminosity function from redshift surveys. It also illustrates how luminosity functions per spectral type may be aected by morphological type mixing, and emphasizes the need for a quantitative morphological classification at z> 0:1 which separates