[论文解读] The BINGO Project I: Baryon Acoustic Oscillations from Integrated Neutral Gas Observations

Élcio Abdalla, Elisa G. M. Ferreira+44 more|Research Explorer (The University of Manchester)|Jul 4, 2021

Radio Astronomy Observations and Technology参考文献 13被引用 9

一句话总结

BINGO项目提出建造一台单孔径射电望远镜，通过低红移中性氢（H i）21厘米强度映射探测重子声学振荡（BAO），并采用专用数据处理流程进行前景清洁和宇宙学参数估计。该项目旨在对暗能量和ΛCDM模型提供具有竞争力的约束，同时还能实现暂现源探测，包括每天探测4–5次信噪比大于3的快速射电暴（FRB）。

ABSTRACT

Observations of the redshifted 21-cm line of neutral hydrogen (HI) are a new and powerful window of observation that offers us the possibility to map the spatial distribution of cosmic HI and learn about cosmology. BINGO (Baryon Acoustic Oscillations [BAO] from Integrated Neutral Gas Observations) is a new unique radio telescope designed to be one of the first to probe BAO at radio frequencies. BINGO has two science goals: cosmology and astrophysics. Cosmology is the main science goal and the driver for BINGO's design and strategy. The key of BINGO is to detect the low redshift BAO to put strong constraints in the dark sector models. Given the versatility of the BINGO telescope, a secondary goal is astrophysics, where BINGO can help discover and study Fast Radio Bursts (FRB) and other transients, Galactic and extragalactic science. In this paper, we introduce the latest progress of the BINGO project, its science goals, describing the scientific potential of the project in each science and the new developments obtained by the collaboration. We introduce the BINGO project and its science goals and give a general summary of recent developments in construction, science potential and pipeline development obtained by the BINGO collaboration in the past few years. We show that BINGO will be able to obtain competitive constraints for the dark sector, and also that will allow for the discovery of several FRBs in the southern hemisphere. The capacity of BINGO in obtaining information from 21-cm is also tested in the pipeline introduced here. There is still no measurement of the BAO in radio, and studying cosmology in this new window of observations is one of the most promising advances in the field. The BINGO project is a radio telescope that has the goal to be one of the first to perform this measurement and it is currently being built in the northeast of Brazil. (Abridged)

研究动机与目标

• 通过中性氢（H i）的21厘米强度映射测量低红移宇宙中的重子声学振荡（BAO）。
• 通过精确的宇宙学测量检验ΛCDM模型并约束暗能量组参数。
• 通过探测快速射电暴（FRB）和研究银河系及河外源，推动天体物理学研究。
• 开发稳健的数据处理流程，用于积分H i发射的图生成、前景去除和宇宙学推断。
• 建造成本效益高、性能优异的射电望远镜，专为南半球宇宙学巡天优化。

提出的方法

• 利用单孔径 transit 望远镜对中性氢（H i）的21厘米线进行大范围、深空巡天。
• 采用强度映射技术，在红移范围 z ≈ 0.13 至 z ≈ 0.45 内构建H i分布的三维图。
• 应用多阶段数据处理流程，包括时间有序数据（TOD）处理、校准、图生成和分量分离以去除前景信号。
• 使用宇宙学估计量（如协方差矩阵、三阶矩和闵可夫斯基函数）从重建的H i图中提取BAO特征。
• 利用真实天空发射模型和仪器特性模拟观测，以验证数据处理流程和观测策略。
• 集成基于HEALPix的天空表示方法，并使用Astropy、NumPy和Healpy等工具进行数据处理和分析。

Figure 1: BINGO telescope site - artist’s view. In this figure we show the hill and the use of the natural inclination of the terrain to place mirrors and horn structure. In this conception the control cabin is located under the service deck.

实验结果

研究问题

• RQ1 BINGO能否通过强度映射在低红移21厘米功率谱中探测到重子声学振荡（BAO）特征？
• RQ2 BINGO通过BAO测量对暗能量和ΛCDM模型的宇宙学约束能达到何种水平？
• RQ3 在信噪比 > 3 的条件下，BINGO在南天区预计的快速射电暴（FRB）探测率是多少？
• RQ4 BINGO数据处理流程在前景清洁和重建原始H i天空分布方面的有效性如何？
• RQ5 BINGO在宇宙学之外对天体物理学研究的贡献有多大，例如在脉冲星研究和暂现源探测方面？

主要发现

• BINGO预计可通过低红移BAO在21厘米功率谱中的探测，对暗能量组和ΛCDM模型提供具有竞争力的约束。
• 该望远镜预计对信噪比 > 3 的快速射电暴（FRB）探测率约为每天4–5次。
• BINGO数据处理流程成功模拟并处理了模拟图，展示了其在分量分离和宇宙学参数估计方面的稳健性。
• 该项目覆盖了红移范围 z ≈ 0.13 至 z ≈ 0.45 内约22 Mpc³的宇宙大体积，包括物质主导向暗能量主导过渡的区域。
• 望远镜的设计与建造正在推进，重点在于低噪声、高效率的前端系统和大孔径光学设计。
• 合作团队已制定全面的科学策略和数据处理流程，并通过模拟和分量建模得到验证。

Figure 2: H i angular power spectra with a bandwidth of 9.33 MHz at redshifts $z=0.127$ (red) and $z=0.449$ (blue) showing the BAO feature.