We study the impact of theoretical uncertainty in the dark matter halo mass function and halo bias on dark energy constraints from imminent galaxy cluster surveys. We find that for an optical cluster survey like the Dark Energy Survey, the accuracy required on the predicted halo mass function to make it an insignificant source of error on dark energy parameters is ≈1%. The analogous requirement on the predicted halo bias is less stringent (≈5%), particularly if the observable-mass distribution can be well constrained by other means. These requirements depend upon survey area but are relatively insensitive to survey depth. The most stringent requirements are likely to come from a survey over a significant fraction of the sky that aims to observe clusters down to relatively low mass, M th ≈ 1013.7 h –1 M ☉; for such a survey, the mass function and halo bias must be predicted to accuracies of ≈0.5% and ≈1%, respectively. These accuracies represent a limit on the practical need to calibrate ever more accurate halo mass and bias functions. We find that improving predictions for the mass function in the low-redshift and low-mass regimes is the most effective way to improve dark energy constraints.
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机译：我们研究了即将来临的星系团调查暗物质晕质量函数和晕偏对暗能量约束的理论不确定性的影响。我们发现，对于像暗能量调查这样的光簇调查，要使光晕质量函数成为暗能量参数上的无关紧要的误差源，所需的预测光晕质量函数的准确度约为1％。对预测的光晕偏差的类似要求不太严格（约5％），尤其是在可观察质量分布可以通过其他方式很好地约束的情况下。这些要求取决于调查区域，但对调查深度相对不敏感。最严格的要求可能来自对很大一部分天空的调查，该调查旨在观察质量相对较低的星团，M th≈1013.7 h –1 M☉;对于这样的调查，必须预测质量函数和晕圈偏差的精确度分别为≈0.5％和≈1％。这些精度代表了校准更精确的光环质量和偏置函数的实际需要的限制。我们发现，改善低红移和低质量状态下质量函数的预测是改善暗能量约束的最有效方法。
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