Using a set of high resolution simulations, we quantify the effect of species-specific initial transfer functions on probes of the intergalactic medium (IGM) via the Lyman-α forest. We focus on redshifts 2–6, after H i reionization. We explore the effect of these initial conditions on measures of the thermal state of the low density IGM: the curvature, Doppler width cutoff, and Doppler width distribution. We also examine the matter and flux power spectrum, and potential consequences for constraints on warm dark matter models. We find that the curvature statistic is at most affected at the $\approx 2{{\ \rm per\ cent}}$ level at z = 6. The Doppler width cutoff parameters are affected by $\approx 5{{\ \rm per\ cent}}$ for the intercept, and $\approx 8{{\ \rm per\ cent}}$ for the fit slope, though this is subdominant to sample variation. The Doppler width distribution shows a $\approx 30{{\ \rm per\ cent}}$ effect at z = 3, however the distribution is not fully converged with simulation box size and resolution. The flux power spectrum is at most affected by $\approx 5{{\ \rm per\ cent}}$ at high redshift and small scales. We discuss numerical convergence with simulation parameters.

中文翻译：

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模拟中单独初始条件对 lyman-α 森林的影响

使用一组高分辨率模拟，我们通过 Lyman-α 森林量化了物种特异性初始传递函数对星际介质 (IGM) 探针的影响。我们关注 H i 再电离后的红移 2-6。我们探讨了这些初始条件对低密度 IGM 热状态测量的影响：曲率、多普勒宽度截止和多普勒宽度分布。我们还研究了物质和通量功率谱，以及对暖暗物质模型的约束的潜在后果。我们发现曲率统计量在 z = 6 时最多在 $\approx 2{{\ \rm per\ cent}}$ 水平上受到影响。多普勒宽度截止参数受 $\approx 5{{\ \rm per\ cent}}$ 用于截距，$\approx 8{{\ \rm per\ cent}}$ 用于拟合斜率，尽管这对样本变化来说是次要的。多普勒宽度分布在 z = 3 处显示 $\约 30{{\ \rm per\ cent}}$ 效应，但是该分布并未完全收敛于模拟框大小和分辨率。在高红移和小尺度下，通量功率谱最多受 $\approx 5{{\ \rm per\ cent}}$ 的影响。我们讨论数值收敛与模拟参数。