论文标题
在Boss DR12中检测各向异性星系组件偏置
Detection of anisotropic galaxy assembly bias in BOSS DR12
论文作者
论文摘要
我们提供了在Baryon振荡光谱调查数据中释放12个Galaxy样品的各向异性星系组装偏置的证据，其水平超过$5σ$。我们使用视线速度色散的测量值$σ_\ star $和恒星质量$ m_ \ star $，对星系的子样本进行简单的拆分。我们表明，功率谱的单极和四极矩的幅度在$σ_\ star $和$ m_ \ star $上的不同取决于不同的取决于$σ_\ star $，从而使我们能够将星系样品分为具有匹配单极的子集，但在所有尺度上都显着不同。结合了Lowz和CMASS NGC星系样品的数据，我们发现$>5σ$ acive的各向异性偏差的证据$ k <0.15 \，h \，h \，\ rm {mpc}^{ - 1} $。我们还使用其他观察到的特性检查了分裂。对于使用$ m_ \ star $和预计尺寸$ r_0 $的星系样品拆分，我们没有发现各向异性偏见的重要证据。使用其他特性选择的星系样品表现出强烈不同程度的各向异性组装偏置，具体取决于使用哪种特性组合来分成子集。这可以解释为什么以前使用基本平面对这种效果进行搜索发现不一致的结果。我们得出的结论是，任何取决于$σ_\ star $的星系样品的选择都可以给出有偏见且不正确的红移空间失真测量值。
We present evidence of anisotropic galaxy assembly bias in the Baryon Oscillation Spectroscopic Survey Data Release 12 galaxy sample at a level exceeding $5σ$. We use measurements of the line-of-sight velocity dispersion $σ_\star$ and stellar mass $M_\star$ to perform a simple split into subsamples of galaxies. We show that the amplitude of the monopole and quadrupole moments of the power spectrum depend differently on $σ_\star$ and $M_\star$, allowing us to split the galaxy sample into subsets with matching monopoles but significantly different quadrupoles on all scales. Combining data from the LOWZ and CMASS NGC galaxy samples, we find $>5σ$ evidence for anisotropic bias on scales $k<0.15\,h\,\rm{Mpc}^{-1}$. We also examine splits using other observed properties. For galaxy samples split using $M_\star$ and projected size $R_0$, we find no significant evidence of anisotropic bias. Galaxy samples selected using additional properties exhibit strongly varying degrees of anisotropic assembly bias, depending on which combination of properties is used to split into subsets. This may explain why previous searches for this effect using the Fundamental Plane found inconsistent results. We conclude that any selection of a galaxy sample that depends on $σ_\star$ can give biased and incorrect Redshift Space Distortion measurements.
