论文标题
在DESI调查中作为RSD污染物的内在对齐
Intrinsic Alignment as an RSD Contaminant in the DESI Survey
论文作者
论文摘要
我们从传统成像调查中测量了发光红星系(LRG)的主要轴的潮汐对齐,并使用它来推断人造红移空间失真特征,该标志将由深色能量光谱仪器(DESI)中的方向依赖性,依赖于方向依赖的,表面亮度选择引起。利用光度红移来减轻由于弱透镜引起的形状密度相关性,我们测量了LRGS的固有潮汐比对。另外,我们估计了从DESI的纤维磁目标选择中的LRG方向的净极化为沿视线的10^-2阶。使用这些测量值和线性潮汐模型,我们预测针对40-80 mpc/h的2分相关函数的四倍函数的四极杆分数下降了0.5%。我们还使用来自Abacus Summit宇宙模拟套件中的Halo目录来重现此假四极杆。
We measure the tidal alignment of the major axes of Luminous Red Galaxies (LRGs) from the Legacy Imaging Survey and use it to infer the artificial redshift-space distortion signature that will arise from an orientation-dependent, surface-brightness selection in the Dark Energy Spectroscopic Instrument (DESI) survey. Using photometric redshifts to down-weight the shape-density correlations due to weak lensing, we measure the intrinsic tidal alignment of LRGs. Separately, we estimate the net polarization of LRG orientations from DESI's fiber-magnitude target selection to be of order 10^-2 along the line of sight. Using these measurements and a linear tidal model, we forecast a 0.5% fractional decrease on the quadrupole of the 2-point correlation function for projected separations of 40-80 Mpc/h. We also use a halo catalog from the Abacus Summit cosmological simulation suite to reproduce this false quadrupole.