论文标题
被困的Lyα冷却辐射有助于抑制原藻中的H2-Cooling
Suppression of H2-cooling in protogalaxies aided by trapped Lyα cooling radiation
论文作者
论文摘要
我们使用高分辨率的三维流体动力模拟研究了紫外线辐射的原子冷却光环的热演化。我们考虑了将lyα冷却辐射捕获在三个此类光环的光学厚的核心中的H^ - 光检查的影响，这一过程尚未包含在先前的模拟中。 H^ - 是分子氢的前体，因此，其破坏会减少H2的丰度和冷却。使用对被困LYα能量密度的简单高端估计值，我们发现LYα的H^ - 光检查可降低关键的UV通量，以抑制H2冷却的最高\ \ 5倍。通过对LYα的更保守的估计，我们发现仅降低了降低关键通量，仅降低了〜15-50％。我们的结果表明，LYα辐射可能对紫外辐照光环的热演化具有重要影响，因此对大规模黑洞形成的潜力可能具有重要影响。
We study the thermal evolution of UV-irradiated atomic cooling haloes using high-resolution three-dimensional hydrodynamic simulations. We consider the effect of H^- photodetachment by Lyα cooling radiation trapped in the optically-thick cores of three such haloes, a process which has not been included in previous simulations. H^- is a precursor of molecular hydrogen, and therefore, its destruction can diminish the H2 abundance and cooling. Using a simple high-end estimate for the trapped Lyα energy density, we find that H^- photodetachment by Lyα decreases the critical UV flux for suppressing H2-cooling by up to a factor of \approx 5. With a more conservative estimate of the Lyα energy density, we find the critical flux is decreased only by ~15-50 percent. Our results suggest that Lyα radiation may have an important effect on the thermal evolution of UV-irradiated haloes, and therefore on the potential for massive black hole formation.
