THE WYOMING SURVEY FOR Hα. II. Hα LUMINOSITY FUNCTIONS AT z≈ 0.16, 0.24, 0.32, AND 0.40
THE WYOMING SURVEY FOR Hα. II. Hα LUMINOSITY FUNCTIONS AT z≈ 0.16, 0.24, 0.32, AND 0.40
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Hα II 的怀俄明州调查。z≈ 0.16、0.24、0.32 和 0.40 时的 Hα 光度函数。
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
S. Staudaher
中科院分区：
文献类型：
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作者：
D. Dale;R. Barlow;Seth A. Cohen;D. Cook;L. Johnson;S. Kattner;C. Moore;M. Schuster;S. Staudaher
怀俄明Hα巡天（whysh）是一项针对Hα发射星系的大面积地面成像巡天，其红移范围分别为z≈0.16、0.24、0.32和0.40。该调查在一组低星系卷云发射场中跨度高达4度2，在每个历元使用双窄带滤波器来改进恒星连续体减法。基于近1200个星系，给出了每个Δz≈0.02 epoch的Hα光度函数。这些数据清楚地表明，随着时间的推移，体积平均宇宙恒星形成率发生了演变。对不完全和消光校正的Hα光度函数的Schechter拟合积分表明，在z ~ 0.16、0.24、0.32和0.40处，每移动体积的恒星形成率分别为0.010、0.013、0.020、0.022 h70 M☉yr - 1 Mpc - 3。统计和系统测量的综合不确定性约为25%，而宇宙方差的影响约为20%。这种演变主要是由Hα光度函数的特征光度L*的变化驱动的，其中前两个时期的L*比后两个时期的L*大2倍；用这个数据集来解释光度函数振幅和暗端斜率的系统进化差异是比较困难的。将这些结果与发射线调查文献的综合汇编结果相结合，测量出宇宙恒星形成速率密度大于0≤z≤1.5的演化。
The Wyoming Survey for Hα, or WySH, is a large-area, ground-based imaging survey for Hα-emitting galaxies at redshifts of z ≈ 0.16, 0.24, 0.32, and 0.40. The survey spans up to 4 deg2 in a set of fields of low Galactic cirrus emission, using twin narrowband filters at each epoch for improved stellar continuum subtraction. Hα luminosity functions are presented for each Δz ≈ 0.02 epoch based on a total of nearly 1200 galaxies. These data clearly show an evolution with look-back time in the volume-averaged cosmic star formation rate. Integrals of Schechter fits to the incompleteness- and extinction-corrected Hα luminosity functions indicate star formation rates per comoving volume of 0.010, 0.013, 0.020, 0.022 h70 M☉ yr−1 Mpc−3 at z ∼ 0.16, 0.24, 0.32, and 0.40, respectively. Combined statistical and systematic measurement uncertainties are on the order of 25%, while the effects of cosmic variance are at the 20% level. The bulk of this evolution is driven by changes in the characteristic luminosity L* of the Hα luminosity functions, with L* for the earlier two epochs being a factor of 2 larger than L* at the latter two epochs; it is more difficult with this data set to decipher systematic evolutionary differences in the luminosity function amplitude and faint-end slope. Coupling these results with a comprehensive compilation of results from the literature on emission line surveys, the evolution in the cosmic star formation rate density over 0 ≲ z ≲ 1.5 is measured to be .