论文标题
Demnuni:在存在大量中微子和动态暗能的情况下比较非线性功率光谱处方
DEMNUni: comparing nonlinear power spectra prescriptions in the presence of massive neutrinos and dynamical dark energy
论文作者
论文摘要
我们提供了与大型宇宙学$ n $体仿真的准确比较,这些模拟在存在大量中微子和动态暗能量的情况下对非线性物质功率谱进行建模。我们测试了当前最广泛使用的方法:拟合功能(halofit和hmcode),卤代模型反应(反应)和仿真器(baccoemu和euclidemulator2)。 Focussing on redshifts $z\leq2$ and scales $k\lesssim 1 \ h/$Mpc (where the simulation mass resolution provides $\sim 1\%$ accuracy), we find that HMcode and ReACT considerably improve over the HALOFIT prescriptions of Smith and Takahashi (both combined with the Bird correction), with an overall agreement of 2\% for all the cosmological scenarios considered.关于仿真器,我们发现,尤其是在低红移时,Euclidemulator2显着与模拟光谱在$ \ lessim 1 \%1 \%$级别的情况下,具有动态的深色中微子和无质量的中微子,达到了$ \ sim 2 \%$ th $ z = 2 $的最大差异。 Baccoemu具有与Euclidemulator2相似的行为,除了几个暗能量模型。在具有大量中微子的宇宙学中,$ z = 0 $所有非线性处方都改善了他们相对于无质量的中微子案例的一致性,除了鸟类和takabird型号外,这些型号并未针对$ w_0 $ - $ w_a $型号量身定制。在$ z> 0 $时,我们在包括大量中微子的情况下没有发现类似的改进,这可能是由于中微子自由流的影响较低,因此较高的红移;而$ z = 2 $ Euclidemulator2超过$ 2 \%$的协议,对于某些黑暗能源方程式。当考虑在给定宇宙学模型中计算出的物质功率谱与其$λ$ CDM对应物之间的比率时,所有经过测试的处方都与模拟数据(根据$ z $不同)的模拟数据一致。 [简略]
We provide an accurate comparison, against large cosmological $N$-body simulations, of different prescriptions for modelling nonlinear matter power spectra in the presence of massive neutrinos and dynamical dark energy. We test the current most widely used approaches: fitting functions (HALOFIT and HMcode), the halo-model reaction (ReACT) and emulators (baccoemu and EuclidEmulator2). Focussing on redshifts $z\leq2$ and scales $k\lesssim 1 \ h/$Mpc (where the simulation mass resolution provides $\sim 1\%$ accuracy), we find that HMcode and ReACT considerably improve over the HALOFIT prescriptions of Smith and Takahashi (both combined with the Bird correction), with an overall agreement of 2\% for all the cosmological scenarios considered. Concerning emulators, we find that, especially at low redshifts, EuclidEmulator2 remarkably agrees with the simulated spectra at $\lesssim 1\%$ level in scenarios with dynamical dark energy and massless neutrinos, reaching a maximum difference of $\sim 2\%$ at $z=2$. baccoemu has a similar behaviour as EuclidEmulator2, except for a couple of dark energy models. In cosmologies with massive neutrinos, at $z=0$ all the nonlinear prescriptions improve their agreement with respect to the massless neutrino case, except for the Bird and TakaBird models which, however, are not tailored to $w_0$--$w_a$ models. At $z>0$ we do not find a similar improvement when including massive neutrinos, probably due to the lower impact of neutrino free-streaming at higher redshifts; rather at $z=2$ EuclidEmulator2 exceeds $2\%$ agreement for some dark energy equation of state. When considering ratios between the matter power spectrum computed in a given cosmological model and its $Λ$CDM counterpart, all the tested prescriptions agree with simulated data, at sub-percent or percent level, depending on $z$. [ABRIDGED]