Massive neutrinos have non-negligible impact on the formation of large-scale structures. We investigate the impact of massive neutrinos on the halo assembly bias effect, measured by the relative halo bias $\hat{b}$ as a function of the curvature of the initial density peak $\hat{s}$, neutrino excess εν, or halo concentration $\hat{c}$, using a large suite of ΣMν = 0.0 eV and 0.4 eV simulations with the same initial conditions. By tracing dark matter haloes back to their initial density peaks, we construct a catalogue of halo ‘twins’ that collapsed from the same peaks but evolved separately with and without massive neutrinos, thereby isolating any effect of neutrinos on halo formation. We detect a 2% weakening of the halo assembly bias as measured by $\hat{b}(\epsilon _\nu )$ in the presence of massive neutrinos. As there exists a significant correlation between $\hat{s}$ and εν (rcc = 0.319), the impact of neutrinos persists at a reduced level (0.1%) in the halo assembly bias measured by $\hat{b}(\hat{s})$. However, we do not detect any neutrino-induced impact on $\hat{b}(\hat{c})$, consistent with earlier studies and the lack of correlation between $\hat{c}$ and εν (rcc = 0.087). We also discover an analogous assembly bias effect for the ‘neutrino haloes’, whose concentrations are anti-correlated with the large-scale clustering of neutrinos.

中文翻译：

---

阐明大量中微子对晕组装偏差的影响

大质量中微子对大规模结构的形成具有不可忽视的影响。我们研究了大质量中微子对晕组装偏差效应的影响，通过相对晕偏差 $\hat{b}$ 来测量，作为初始密度峰值 $\hat{s}$ 曲率的函数，中微子过量 εν，或晕浓度 $\hat{c}$，使用大量具有相同初始条件的 ΣMν = 0.0 eV 和 0.4 eV 模拟。通过追踪暗物质晕回到它们最初的密度峰值，我们构建了一个晕“双胞胎”目录，它们从相同的峰值坍塌，但在有或没有大量中微子的情况下分别演化，从而隔离了中微子对晕形成的任何影响。我们发现，在存在大量中微子的情况下，通过 $\hat{b}(\epsilon _\nu )$ 测量，光环组装偏差减弱了 2%。由于 $\hat{s}$ 和 εν (rcc = 0.319) 之间存在显着相关性，因此中微子的影响在通过 $\hat{b}(\帽子{s})$。然而，我们没有检测到任何中微子对 $\hat{b}(\hat{c})$ 的影响，这与早期的研究一致，并且 $\hat{c}$ 和 εν 之间缺乏相关性 (rcc = 0.087 ）。我们还发现了“中微子晕”的类似组装偏差效应，其浓度与中微子的大规模聚集呈反相关。