Line-of-Sight Integrated Radio Emission in Underdense Regions: A Multi-Scale Test of a Density-Dependent Scalar Field Model

We present a multi-scale observational analysis of radio residuals in underdense cosmic environments using NVSS (1.4 GHz) and LoTSS DR2 (144 MHz) data. Main Results NVSS stacking and individual sightline tests reveal a suggestive environmental hierarchy: positive radio excesses are strongest and most consistent in the cleanest underdense regions (cosmic voids and South Galactic Pole) and are suppressed in high-density environments (galaxy clusters). In contrast, a rigorous Monte Carlo analysis of LoTSS DR2 residuals in the Boötes and Lockman Hole deep fields yields a clean null detection, with negligible effect sizes and distributions statistically indistinguishable from background controls. This GHz–MHz spectral tension is the central observational finding of the work.本研究利用甚大阵天空巡天（NVSS，1.4 GHz）与LoTSS DR2（144 MHz）观测数据，对低密度宇宙环境中的射电残差开展多尺度观测分析。 主要研究结果 NVSS堆叠分析与单条视线测试均揭示出具有启发性的环境分层特征：在最纯净的低密度区域（宇宙空洞与南银极）中，正射电超额现象最为显著且一致性最强，而在高密度环境（星系团）中该现象则受到显著抑制。 与之形成鲜明对比的是，针对牧夫座与洛克曼空洞深场中的LoTSS DR2残差开展的严谨蒙特卡洛分析，得到了干净的零检测结果，其效应量可忽略不计，分布与背景对照组在统计学上无显著差异。 这种GHz与MHz频段间的频谱张力，正是本研究的核心观测发现。