论文标题
用万神殿样品测试宇宙各向异性,并在高红移处进行类星体
Testing cosmic anisotropy with Pantheon sample and quasars at high redshifts
论文作者
论文摘要
在本文中,我们通过采用半球比较(HC)方法(HC)方法和偶极拟合(DF)方法研究了由SN-Q样品的宇宙各向异性。与Pantheon样品相比,新样品的红移范围更大,分布更均匀和较大的样本量。对于HC方法,我们发现最大各向异性级别为$ al_ {max} = 0.142 \ pm0.026 $在方向上($ l $,$ b $)= $({316.08^{\ circ}}} $ {4.53^{\ circ}}}^{+26.29} _ { - 64.06})$。 The magnitude of anisotropy is $A$ = ($-$8.46 $^{+4.34}_{-5.51}$)$\times$$10^{-4}$ and the corresponding preferred direction points toward $(l$, $b)$ = ($29.31^{\circ}$$^{+30.59}_{-30.54}$, $ 71.40^{\ circ} $$^{+9.79} _ { - 9.72} $)来自DF方法的类星体样本。组合的SN和类星体样品与各向同性假设一致。数据集的分布可能会影响偶极子结果的首选方向。结果微弱地取决于红移断层扫描分析的红移。 SN-Q样品中没有宇宙各向异性的证据。尽管从类星体样品中获得的一些结果与标准宇宙学模型不一致,但在SN-Q样品中,我们仍然找不到宇宙各向异性的任何不同证据。
In this paper, we investigate the cosmic anisotropy from the SN-Q sample, consisting of the Pantheon sample and quasars, by employing the hemisphere comparison (HC) method and the dipole fitting (DF) method. Compared to the Pantheon sample, the new sample has a larger redshift range, a more homogeneous distribution, and a larger sample size. For the HC method, we find that the maximum anisotropy level is $AL_{max}=0.142\pm0.026$ in the direction ($l$, $b$) = $({316.08^{\circ}}^{+27.41}_{-129.48}$, ${4.53^{\circ}}^{+26.29}_{-64.06})$. The magnitude of anisotropy is $A$ = ($-$8.46 $^{+4.34}_{-5.51}$)$\times$$10^{-4}$ and the corresponding preferred direction points toward $(l$, $b)$ = ($29.31^{\circ}$$^{+30.59}_{-30.54}$, $71.40^{\circ}$$^{+9.79}_{-9.72}$) for the quasar sample from the DF method. The combined SN and quasar sample is consistent with the isotropy hypothesis. The distribution of the dataset might impact the preferred direction from the dipole results. The result is weakly dependent on the redshift from the redshift tomography analysis. There is no evidence of cosmic anisotropy in the SN-Q sample. Though some results obtained from the quasar sample are not consistent with the standard cosmological model, we still do not find any distinct evidence of cosmic anisotropy in the SN-Q sample.