发表机构
Université Paris-Saclay; CEA; Department of Physics, Durham University; Institute for Computational Cosmology, Department of Physics, Durham University; Université Paris Cité; CNRS; AIM（巴黎萨克雷大学; 法国原子能和替代能源委员会; 杜伦大学物理系; 杜伦大学计算宇宙学研究所; 巴黎西岱大学; 法国国家科学研究中心; 天体物理学与分子研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出球面质量孔径工具包SMART，将孔径质量方法推广至天球，实现快速精确的球面孔径质量图计算，较现有方法精度更高、速度提升达40倍，并改善弱透镜星系团探测性能。
AI 中文摘要
孔径质量滤波器是弱引力透镜研究中广泛使用的工具。以往巡天通常依赖于平面天近似，而即将到来的第四阶段巡天（如欧几里得卫星）将覆盖足够大的天区，因此需要构建曲面天球上的孔径质量图。在本文中，我们将基于剪切的孔径质量形式体系推广到球面，并引入一个软件包，用于直接从剪切场快速、精确地计算球面孔径质量图，该图直接定义在天球上。与现有方法不同，我们的方法不依赖于平面投影，也不需要重建收敛图。该软件提供了四种不同的实现，所有实现均独立于孔径质量滤波函数的选择。从暴力计算法开始（其计算成本使其无法用于覆盖超过10000平方度的未来巡天），我们研究了替代的星系分组策略以提高计算效率。我们展示了在NSIDE=4096的分辨率下，加速比高达40倍，同时实现了比现有最先进方法显著更高的精度。特别地，我们表明，基于像素方法的球面剪切实现，在精度和计算时间方面均优于现有方法。最后，我们证明，对于弱引力透镜星系团探测，使用基于球面剪切的孔径质量方法产生的星系团样本，在纯度-完备性平面上始终优于使用投影剪切方法获得的样本，同时简化了所得的选择函数。我们的球面质量孔径软件名为SMART，已在GitHub上提供。
英文摘要
The aperture mass filter is a widely used tool in weak lensing studies. While previous surveys have typically relied on the flat-sky approximation, forthcoming Stage IV surveys such as Euclid will cover sufficiently large areas to require the construction of curved-sky aperture mass maps. In this paper, we extend the shear-based aperture mass formalism to the sphere and introduce a software package for a fast and precise computation of spherical aperture mass maps from the shear field, defined directly on the celestial sphere. Unlike existing approaches, our method does not rely on planar projections and does not require the reconstruction of convergence maps. The software provides four different implementations, all of which are independent of the choice of aperture mass filter function. Starting from the brute-force approach, whose computational cost renders it impractical for future surveys covering more than 10,000 deg2, we investigate alternative galaxy-grouping strategies to improve computational efficiency. We demonstrate speed-up factors of up to 40 at a resolution of NSIDE = 4096 while achieving significantly higher precision than existing state-of-the-art methods. In particular, we show that the spherical shear-based implementations using a pixel-based approach outperforms the existing methods in terms of both precision and computational time. Finally, we show that, for weak-lensing cluster detection, the cluster sample produced using the spherical shear-based aperture mass method consistently outperforms those obtained using projected shear-based approaches in the purity-completeness plane, while simplifying the resulting selection function. Our spherical mass aperture software, called SMART, is made available on GitHub.
Comments12 pages, 7 figures, submitted to A&A
