论文标题
光环自旋转变作为暗能量的探针
The Halo Spin Transition as a Probe of Dark Energy
论文作者
论文摘要
我们提供了一个数值证据，支持这一说法，即光环旋转方向从中间体到局部潮汐场的次要主要方向的质量依赖性过渡，原则上可以是暗能能模型的有用歧视者。我们首先将自旋过渡区定义为光晕的质量范围，$Δm_{t} $，因此，与中间主方向的固有旋转对齐相对的固有旋转对准与中间的旋转对齐一样强。然后，利用来自DEUS模拟的Halo样品，分别针对WMAP7 $λ$ CDM，Phantom de和Quintessence模型执行，我们研究了三种不同的暗能量模型在$Δm_{t} $中是否有何不同。结果表明，这三个暗能量模型中$Δm_{t} $的差异足以区分彼此的模型，并与潮汐场和红移的平滑尺度的变化进行稳健。我们还指出，随着暗能量的探测，较窄的旋转过渡区更加强大，我们还表明，在较高的红移，丝状环境中，旋转过渡区变得更窄，并且对于较小尺度上的潮汐场平滑的情况。我们的结果与$Δm_{t} $的情况一致，主要取决于潮汐场的非线性演化的速度，而潮汐场的非线性演化又依赖于背景宇宙学。
We present a numerical evidence supporting the claim that the mass-dependent transitions of the halo spin orientations from the intermediate to the minor principal directions of the local tidal fields can in principle be a useful discriminator of dark energy models. We first define a spin transition zone as the mass range of the halos, $Δm_{t}$, for which the intrinsic spin alignments with the minor tidal principal directions become as strong as that with the intermediate principal directions. Then, utilizing the halo samples from the DEUS simulations performed separately for the WMAP7 $Λ$CDM, phantom DE and quintessence models, we investigate if and how the three different dark energy models differ in $Δm_{t}$. It is shown that the differences in $Δm_{t}$ among the three dark energy models are significant enough to discriminate the models from one another and robust against the variations of the smoothing scale of the tidal field and redshift. Noting that a narrower spin transition zone is more powerful as a probe of dark energy, we also show that the spin transition zones become narrower at higher redshifts, in the filamentary environments and for the case that the tidal fields are smoothed on the smaller scales. Our result is consistent with the scenario that $Δm_{t}$ is mainly determined by how fast the nonlinear evolution of the tidal field proceeds, which in turn sensitively depends on the background cosmology.
