The SCUBA HAlf Degree Extragalactic Survey (SHADES) - VII. Optical/IR photometry and stellar masses of submillimetre galaxies
The SCUBA HAlf Degree Extragalactic Survey (SHADES) - VII. Optical/IR photometry and stellar masses of submillimetre galaxies
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水肺半度河外巡天 (SHADES) - VII。
DOI：
10.1111/j.1365-2966.2008.13113.x
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发表时间：
2008
影响因子：
4.8
通讯作者：
Dye S
中科院分区：
文献类型：
--
作者：
Dye S
我们提出的光度红移，恒星质量和星星的形成历史的来源，在亚毫米波共同用户测辐射热仪阵列（SCUBA）半度河外巡天（SHADES）的估计。本文介绍了在面积为320 arcmin ~ 2的洛克曼洞探测到的60个潜水源。利用B波段至8 μm的测光方法，我们发现平均SCUBA源在星星形成的早期形成了相当大一部分恒星，而其余的大部分在观测到的红移附近形成了一个较短的更强烈的爆发。这种趋势并不随源红移而显著变化。然而，这些资料显示，随着红移，恒星质量明显增加，与缩小一致。在光谱能量分布类型方面，在我们获得光度红移的51个源中，只有两个最适合类星体光谱，大约80%的源最适合晚型光谱（Sc，Im和星爆）。通过包括850 μm的测光，我们得出结论，平均SCUBA源正在形成恒星的速度在6到30倍之间的速度暗示从静止框架光学在尘埃遮蔽的爆发，这种爆发创造了15- 65%的总恒星质量。通过一个简单的计算，我们从平均星星形成历史中估计，在0 <z< 3的区间内，五分之一到十五分之一的明亮星系（L*+ 2 <L光学<L*− 1等）将在其一生中的某个时刻经历类似的星星形成的高能尘埃爆发。最后，我们计算了星星形成率密度的演化，发现它在z ~ 2附近达到峰值。
We present estimates of the photometric redshifts, stellar masses and star formation histories of sources in the Submillimetre Common-User Bolometer Array (SCUBA) HAlf Degree Extragalactic Survey (SHADES). This paper describes the 60 SCUBA sources detected in the Lockman Hole covering an area of ∼320 arcmin2. Using photometry spanning theBband to 8 μm, we find that the average SCUBA source forms a significant fraction of its stars in an early period of star formation and that most of the remainder forms in a shorter more intense burst around the redshift it is observed. This trend does not vary significantly with source redshift. However, the sources show a clear increase in stellar mass with redshift, consistent with downsizing. In terms of spectral energy distribution types, only two out of the 51 sources we have obtained photometric redshifts for are best fitted by a quasar-like spectrum, with approximately 80 per cent of the sources being best fitted with late-type spectra (Sc, Im and starburst). By including photometry at 850 μm, we conclude that the average SCUBA source is forming stars at a rate somewhere between 6 and 30 times the rate implied from the rest-frame optical in a dust obscured burst and that this burst creates 15–65 per cent of the total stellar mass. Using a simplistic calculation, we estimate from the average star formation history that between one in five and one in 15 bright (L*+ 2 <Loptical<L*− 1 mag) galaxies in the field over the interval 0 <z< 3 will at some point in their lifetime experience a similar energetic dusty burst of star formation. Finally, we compute the evolution of the star formation rate density and find it peaks aroundz∼ 2.