Stellar masses and star formation histories for 105 galaxies from the Sloan Digital Sky Survey
Stellar masses and star formation histories for 105 galaxies from the Sloan Digital Sky Survey
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DOI：
10.1046/j.1365-8711.2003.06291.x
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发表时间：
2002-04
影响因子：
4.8
通讯作者：
G. Kauffmann;T. Heckman;S. White;S. Charlot;C. Tremonti;J. Brinchmann;G. Bruzual;E. Peng;M. S
中科院分区：
文献类型：
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作者：
G. Kauffmann;T. Heckman;S. White;S. Charlot;C. Tremonti;J. Brinchmann;G. Bruzual;E. Peng;M. S
我们发展了一种新的方法来约束星系的星星形成历史、尘埃衰减和恒星质量。它基于两个恒星吸收线指数，4000-A断裂强度和巴尔末吸收线指数Hδ A。总之，这些指数使我们能够约束星系的平均恒星年龄和过去几个Gyr爆发中形成的恒星质量分数。与宽带测光的比较，然后产生估计的尘埃衰减和恒星质量。我们产生了一个大型图书馆的Monte Carlo实现不同的星星形成的历史，包括不同强度和金属丰度的星爆。我们使用这个库来生成中值似然估计的爆发质量分数，尘埃衰减强度，恒星质量和恒星质量光比的样本122 808个星系从斯隆数字巡天。在我们估计的恒星质量的典型95%的置信范围是'40%.We研究如何恒星的质量光比的星系的绝对星等，浓度指数和光度通带的函数的变化，以及如何尘埃衰减的绝对星等和4000-A的断裂强度的函数的变化。我们还计算了当前宇宙的总恒星质量如何分布在星系中，作为它们的质量，大小，浓度，颜色，爆发质量分数和表面质量密度的函数。我们发现，在本地宇宙中的大部分恒星质量居住在星系，有，在一个约2的因素，恒星质量105 × 10 10 M O。半光半径为1.3kpc，半光表面质量密度为1.109M O·kpc - 2。Dn（4000）的分布是强烈的双峰，显示出一个明确的划分之间的星系占主导地位的老恒星人口和星系与更近的星星形成。
We develop a new method to constrain the star formation histories, dust attenuation and stellar masses of galaxies. It is based on two stellar absorption-line indices, the 4000-A break strength and the Balmer absorption-line index Hδ A . Together, these indices allow us to constrain the mean stellar ages of galaxies and the fractional stellar mass formed in bursts over the past few Gyr. A comparison with broad-band photometry then yields estimates of dust attenuation and of stellar mass. We generate a large library of Monte Carlo realizations of different star formation histories, including starbursts of varying strength and a range of metallicities. We use this library to generate median likelihood estimates of burst mass fractions, dust attenuation strengths, stellar masses and stellar mass-to-light ratios for a sample of 122 808 galaxies drawn from the Sloan Digital Sky Survey. The typical 95 per cent confidence range in our estimated stellar masses is ′40 per cent. We study how the stellar mass-to-light ratios of galaxies vary as a function of absolute magnitude, concentration index and photometric passband and how dust attenuation varies as a function of absolute magnitude and 4000-A break strength. We also calculate how the total stellar mass of the present Universe is distributed over galaxies as a function of their mass, size, concentration, colour, burst mass fraction and surface mass density. We find that most of the stellar mass in the local Universe resides in galaxies that have, to within a factor of approximately 2, stellar masses ∼5 x 10 1 0 M O ., half-light radii ∼3 kpc and half-light surface mass densities ∼10 9 M O .kpc - 2 . The distribution of D n (4000) is strongly bimodal, showing a clear division between galaxies dominated by old stellar populations and galaxies with more recent star formation.