Cosmic Histories of Stars, Gas, Heavy Elements, and Dust in Galaxies
Cosmic Histories of Stars, Gas, Heavy Elements, and Dust in Galaxies
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星系中恒星、气体、重元素和尘埃的宇宙历史
DOI：
10.1086/307674
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
M. Hauser
中科院分区：
文献类型：
--
作者：
Y. Pei;S. M. Fall;M. Hauser
我们研究了一组耦合方程，涉及恒星，气体，化学和辐射的宇宙平均在整个人口的星系的内容。作为输入的类星体的吸收线调查，光学成像和红移调查，和COBE DIRBE和FIRAS河外红外背景测量的可用数据，我们得到的恒星，星际气体，重元素，尘埃，和辐射的宇宙历史的解决方案，从恒星和尘埃在星系。我们的解决方案非常好地再现了各种各样的观察，没有被用作输入。这些数据包括：从近紫外到近红外波段的星系计数得到的综合背景光，星系巡天得到的不同红移处的静止坐标系光学和近红外发射率，IRAS巡天得到的局部宇宙的中红外和远红外发射率，阻尼Lyα系统巡天得到的不同时期重元素的平均丰度，和全球星星形成率在几个红移从Hα，中红外，亚毫米观测。我们的模型所暗示的星系际介质的化学富集历史也与观测到的高红移Lyα森林的平均金属含量相一致。我们推断，与恒星形成区相关的尘埃是高度不均匀的，吸收了相当大一部分星光，只有41%-46%的星光在河外光学背景中，其余的59%-54%被尘埃重新加工成红外背景。这里提出的解决方案提供了一个有趣的图片宇宙平均历史的星系在哈勃望远镜的时间。特别是，星系形成的过程似乎经历了一个早期的大量流入，以聚集星际气体在z 103，随后的时期，激烈的星星形成和化学富集在1 z 103，和最近一段时间的气体含量，星星形成率，光学恒星发射率，红外尘埃发射率在z 101下降。
We investigate a set of coupled equations that relates the stellar, gaseous, chemical, and radiation contents of the universe averaged over the whole population of galaxies. Using as input the available data from quasar absorption-line surveys, optical imaging and redshift surveys, and the COBE DIRBE and FIRAS extragalactic infrared background measurements, we obtain solutions for the cosmic histories of stars, interstellar gas, heavy elements, dust, and radiation from stars and dust in galaxies. Our solutions reproduce remarkably well a wide variety of observations that were not used as input. These include the integrated background light from galaxy counts from near-ultraviolet to near-infrared wavelengths, the rest-frame optical and near-infrared emissivities at various redshifts from surveys of galaxies, the mid-infrared and far-infrared emissivities of the local universe from the IRAS survey, the mean abundance of heavy elements at various epochs from surveys of damped Lyα systems, and the global star formation rates at several redshifts from Hα, mid-infrared, and submillimeter observations. The chemical enrichment history of the intergalactic medium implied by our models is also consistent with the observed mean metal content of the Lyα forest at high redshifts. We infer that the dust associated with star-forming regions is highly inhomogeneous and absorbs a significant fraction of the starlight, with only 41%-46% of the total in the extragalactic optical background and the remaining 59%-54% reprocessed by dust into the infrared background. The solutions presented here provide an intriguing picture of the cosmic mean history of galaxies over much of the Hubble time. In particular, the process of galaxy formation appears to have undergone an early period of substantial inflow to assemble interstellar gas at z ≳ 3, a subsequent period of intense star formation and chemical enrichment at 1 ≲ z ≲ 3, and a recent period of decline in the gas content, star formation rate, optical stellar emissivity, and infrared dust emissivity at z ≲ 1.