利用ACT DR6和DESI DR1光谱星系及光学选择星系团测量热Sunyaev-Zel'dovich效应的光学深度
Optical Depths from the Thermal Sunyaev-Zel'dovich Effect with ACT DR6 and DESI DR1 Spectroscopic Galaxies and Optically-Selected Clusters
- Duke University（杜克大学）
- Cornell University（康奈尔大学）
- Ludwig-Maximilians-Universität（慕尼黑大学）
- Max-Planck-Institut für extraterrestrische Physik (MPE)（马克斯·普朗克地外物理研究所）
- Institute of Astronomy and Astrophysics, Academia Sinica (ASIAA)（中央研究院天文及天文物理学研究所）
- University of Pennsylvania（宾夕法尼亚大学）
- University of Cambridge（剑桥大学）
- University of California, Berkeley（加州大学伯克利分校）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本文利用ACT DR6和DESI DR1数据，对三个星系团样本进行叠加tSZ测量，发展$\bar y-\bar \tau$标度关系以推断光学深度，结果与运动学SZ测量一致。
AI中文摘要：
我们展示了针对三个星系群和星系团样本的叠加热Sunyaev-Zel'dovich (tSZ)效应测量：由暗能量光谱仪器数据发布1 (DESI DR1) 亮红星系 (LRG) 和DESI DR1亮星系样本 (BGS) 示踪的样本，以及来自DESI遗产成像巡天的eROMaPPer光学选择样本。我们使用最新的阿塔卡马宇宙学望远镜DR6 (ACT)+Planck分量分离内线性组合 (ILC) Compton-$y$图和ACT+Planck共加的90、150和220 GHz温度图，在$\sim2'$盘状孔径内提取按光度、 richness 或质量分箱的源的tSZ信号。我们以高统计显著性测量平均tSZ信号，使用90 GHz ACT DR6+Planck图，LRG、BGS和eROMaPPer样本的信噪比分别超过38、27和39。我们对系统效应和前景（如尘埃和宇宙红外背景 (CIB) 污染）进行了详细研究，这些仍是tSZ分析的核心挑战。对于LRG和BGS样本，我们发现尘埃和射电源发射在接近和低于盘状孔径半径的尺度上主导tSZ信号。来自CIB的大尺度 ($R>4'$) 污染不太显著。我们减轻这些污染物以分离tSZ信号，并结合模拟和实际测量来发展Compton-$y$-光学深度 ($\bar y-\bar \tau$) 标度关系以推断光学深度，发现这些光学深度与使用相同示踪样本的成对运动学SZ效应测量的值一致。eROMaPPer样本的$\bar y-\bar \tau$标度关系是首个直接从SZ测量推导出的此类关系。
英文摘要：
We present stacked thermal Sunyaev-Zel'dovich (tSZ) effect measurements for three samples of galaxy groups and clusters: those traced by the Dark Energy Spectroscopic Intstrument Data Release 1 (DESI DR1) luminous red galaxies (LRG) and the DESI DR1 Bright Galaxy Sample (BGS), and an eROMaPPer optically-selected sample from the DESI Legacy Imaging Survey. We use the latest Atacama Cosmology Telescope DR6 (ACT)+Planck component-separated internal linear combination (ILC) Compton-$y$ maps and ACT+Planck coadded 90, 150, and 220 GHz temperature maps to extract the tSZ signal within a $\sim2'$ disk aperture for sources binned by luminosity, richness, or mass. We measure the average tSZ signal with high statistical significance, with signal-to-noise ratios surpassing 38 for LRG, 27 for BGS, and 39 for the eROMaPPer sample using the 90 GHz ACT DR6+Planck map. We conduct a detailed study of systematics and foregrounds such as dust and cosmic infrared background (CIB) contamination, which remain a core challenge for tSZ analysis. For the LRG and BGS samples, we find that dust and radio source emission dominate the tSZ signal at scales near and below the disk aperture radius. Large-scale ($R>4'$) contamination from the CIB is less significant. We mitigate these contaminants to isolate the tSZ signal and use a combination of simulated and real measurements to develop Compton-$y-$optical depth ($\bar y-\bar τ$) scaling relations to infer optical depths, which are found to be in agreement with values measured using the pairwise kinematic SZ effect for the same tracer samples. The $\bar y-\bar τ$ scaling relation for the eROMaPPer sample is the first such relationship to be derived directly from SZ measurements.
