arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2201.02632astro-ph.CO
收藏

重子粘贴算法:基于晕和基于粒子的粘贴方法

Baryon Pasting Algorithm: Halo-based and Particle-based Pasting Methods

Ken Osato, Daisuke Nagai

摘要:

我们提出了一种快速的方法来产生模拟观测的热和动力学Sunyaev-Zel'dovich(SZ)的基础上的暗物质只有$N$体模拟与分析的集群内介质模型。该方法采用两种不同的方法:基于光晕的粘贴(HP)和基于颗粒的粘贴(PP)。前者将气体密度和压力粘贴到晕上,只需要一个晕目录,而后者也考虑了场粒子的贡献,即,不属于任何晕圈的粒子,从而利用全部粒子信息。因此,PP算法结合了HP算法之外的二次效应:光晕的非球面性和扩散气体的贡献。特别是,这样的扩散分量是动力学SZ效应的主要来源。为了验证我们的方法,我们制作了108张全天空HP图和108张平天图,其中包括$5 \times 5 \, \mathrm{deg}^2$与HP和PP,并测量了地图的功率谱。我们的方法可以在几个小时内生成一个模拟地图,即使是在并行计算环境下的全天空覆盖。HP图的功率谱与热SZ效应的晕模型预测一致。另一方面,由于晕的非球面性,PP图的功率谱被抑制,但可以更好地再现动力学SZ效应的理论预测。我们讨论了重子粘贴模拟SZ地图估计SZ统计的协方差矩阵和模拟集群宇宙学的选择和投影效应的效用。

英文摘要:

We present a fast methodology to produce mock observations of the thermal and kinetic Sunyaev-Zel'dovich (SZ) effects based on the dark matter only $N$-body simulations coupled with the analytic intra-cluster medium model. The methods employ two different approaches: halo-based pasting (HP) and particle-based pasting (PP). The former pastes gas density and pressure onto halos and requires only a halo catalogue, and the latter considers the contribution from field particles as well, i.e., particles that do not belong to any halos and thus utilise the full particle information. Therefore, the PP algorithm incorporates secondary effects beyond the HP algorithm: asphericity of halos and contribution from diffuse gas. In particular, such a diffuse component is the dominant source of the kinetic SZ effect. As validation of our methods, we have produced 108 all-sky maps with HP and 108 flat-sky maps, which cover $5 \times 5 \, \mathrm{deg}^2$ with both HP and PP, and measured power spectra of the maps. Our method can produce a mock map within a few hours, even for all-sky coverage with a parallel computational environment. The power spectra of HP maps are consistent with the halo model prediction of the thermal SZ effect. On the other hand, the power spectra of PP maps are suppressed due to the halo asphericity but can reproduce better the theoretical prediction for the kinetic SZ effect. We discuss the utility of baryon-pasted mock SZ maps for estimating the covariance matrix of SZ statistics and modelling the selection and projection effects for cluster cosmology.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑