论文标题
检测和应用星系与大规模速度场对齐的前景
Prospects for detection and application of the alignment of galaxies with the large-scale velocity field
论文作者
论文摘要
内在比对效应的研究主要集中在星系形状之间的相关性，或与宇宙大规模结构的基础密度场之间的相关性。最近，已经提出了星系形状与大规模速度场之间的相关性，作为大规模结构的附加探针。我们使用Fisher的预测来预测这种速度形状相关性的可检测性，并结合了来自4个+LSST调查的红移和形状的组合，以及Simons天文台的径向速度重建。速度形状（偶极子）相关性的信噪比为7.4，相对于星系密度形状（单极）相关的44，最大波数为$ 0.2 \：\ mathrm {mpc^{ - 1}}} $。在这些预测的鼓励下，我们讨论了速度形状相关性的两个可能的应用。测量速度形状的相关性可以改善因固有比对在星系聚类中引起的选择效应的缓解。我们还发现，当提供同一星系的多个形状测量值时，速度形状测量可能有助于确定固有比对的规模依赖性。
Studies of intrinsic alignment effects mostly focus on the correlations between shapes of galaxies with each other, or with the underlying density field of the large scale structure of the universe. Lately, the correlation between shapes of galaxies and the large-scale velocity field has been proposed as an additional probe of the large scale structure. We use a Fisher forecast to make a prediction for the detectability of this velocity-shape correlation with a combination of redshifts and shapes from the 4MOST+LSST surveys, and radial velocity reconstruction from the Simons Observatory. The signal-to-noise ratio for the velocity-shape (dipole) correlation is 7.4, relative to 44 for the galaxy density-shape (monopole) correlation and for a maximum wavenumber of $0.2\: \mathrm{Mpc^{-1}}$. Encouraged by these predictions, we discuss two possible applications for the velocity-shape correlation. Measuring the velocity-shape correlation could improve the mitigation of selection effects induced by intrinsic alignments on galaxy clustering. We also find that velocity-shape measurements could potentially aid in determining the scale-dependence of intrinsic alignments when multiple shape measurements of the same galaxies are provided.
