论文标题
CMB在物理模型上的约束
CMB constraints on a physical model of reionization
论文作者
论文摘要
我们通过比较宇宙微波背景（CMB）的二级温度和极化各向异性的物理半数字模型的预测来研究允许的回离历史的限制。我们的模型具有四个自由参数，这些参数表征了电离效率$ζ$的演变和最小质量$ m _ {\ mathrm {min}} $，这些光环的光环可以产生电离辐射。将模型预测与当前可用的光学深度$τ$和运动式Sunyaev-Zeldovich信号的数据进行比较，我们发现我们已经可以排除参数空间的重要区域。我们限制了电源的持续时间$Δz= 1.30^{+0.19} _ { - 0.60} $（$Δz<2.9 $ at $ 99 \％$ c.l.），这是参数最紧密的约束之一。约束温和偏爱$ m _ {\ mathrm {minrm {min}} \ gtrsim 10^9 \ mathrm {m} _ {\ odot} $（$ z \ sim 8 $，$ 68 \％$ c.l.），从而表明存在回电反馈。我们的分析提供了次级$ b $ -mode振幅$ d_ {l = 200}^{bb} <18 $ nk $^2 $ at $ 99 \％$ c.l.的上限。我们还研究了如何通过即将进行的空间和地面CMB任务进一步收紧约束。我们的研究仅依赖于CMB数据，不仅对即将进行的CMB调查具有检测原始引力波的影响，而且还具有红移21 CM研究。
We study constraints on allowed reionization histories by comparing predictions of a physical semi-numerical model with secondary temperature and polarization anisotropies of the cosmic microwave background (CMB). Our model has four free parameters characterizing the evolution of ionizing efficiency $ζ$ and the minimum mass $M_{\mathrm{min}}$ of haloes that can produce ionizing radiation. Comparing the model predictions with the presently available data of the optical depth $τ$ and kinematic Sunyaev-Zeldovich signal, we find that we can already rule out a significant region of the parameter space. We limit the duration of reionization $Δz=1.30^{+0.19}_{-0.60}$ ($Δz < 2.9$ at $99\%$ C.L.), one of the tightest constraints on the parameter. The constraints mildly favour $M_{\mathrm{min}} \gtrsim 10^9 \mathrm{M}_{\odot}$ (at $68\%$ C.L.) at $z \sim 8$, thus indicating the presence of reionization feedback. Our analysis provides an upper bound on the secondary $B$-mode amplitude $D_{l=200}^{BB}<18$ nK$^2$ at $99\%$ C.L. We also study how the constraints can be further tightened with upcoming space and ground-based CMB missions. Our study, which relies solely on CMB data, has implications not only for upcoming CMB surveys for detecting primordial gravitational waves but also redshifted 21 cm studies.
