Core Insights - An international team led by the University of Oxford has successfully created a plasma "fireball" in a laboratory setting using CERN's Super Proton Synchrotron, simulating the process of quasar jets propagating through interstellar space, providing new clues to the mystery of "missing gamma rays" in the universe [1][2] Group 1: Research Findings - Quasars, driven by supermassive black holes, emit narrow, near-light-speed jets of particles and radiation, producing extremely high-energy gamma rays, which can reach several TeV [1] - Theoretical models suggest that these high-energy gamma rays scatter with background starlight in interstellar space, generating electron-positron pairs, which should interact with cosmic microwave background to produce lower-energy gamma rays that have not been detected by satellite telescopes [1][2] Group 2: Experimental Methodology - To test existing theories, the research team utilized CERN's high-radiation materials facility to generate electron-positron pairs and allowed them to pass through a one-meter-long plasma, creating an experimental model of quasar jet propagation in interstellar space [2] - The experiment measured particle beam morphology and magnetic field signals, directly testing whether "jet-plasma instability" could disrupt the jet structure [2] Group 3: Conclusions and Implications - The experiment demonstrated that the particle beam maintained a narrow, nearly parallel shape with minimal disturbances or spontaneous magnetic fields, suggesting that instability effects are too weak to explain the missing low-energy gamma rays [2] - This finding supports the hypothesis that extremely weak interstellar magnetic fields, possibly remnants of the early universe's "primordial magnetic field," exist [2] - The research represents a significant step in understanding high-energy astrophysical jets and the origins of magnetic fields, with future observational facilities like the Cherenkov Telescope Array expected to provide higher resolution data to further validate these theories [2]

由英国牛津大学领衔的国际团队利用欧洲核子研究中心（CERN）的超级质子同步加速器，首次在实验 室制造出等离子体"火球"，模拟了类星体耀变体喷流在星际空间传播的过程，为破解宇宙中"消失的伽 马射线"之谜提供了新线索。相关成果发表于新一期《美国国家科学院院刊》。 （文章来源：科技日报） 为验证这些观点，研究团队在CERN的高辐射材料实验设施中，利用超级质子同步加速器产生电子—正 电子对，并让它们穿过一米长的等离子体，构建出类星体喷流在星际空间传播的实验模型。通过精确测 量粒子束形态及磁场信号，研究人员首次在实验室中直接检验了"喷流—等离子体不稳定性"是否足以破 坏喷流结构。 实验显示，粒子束始终保持狭窄、几乎平行的形态，几乎没有出现显著扰动或自发磁场。团队据此推 断，在天体尺度上，这种不稳定性效应过弱，无法解释缺失的低能伽马射线。这一结论反而强化了另一 种解释，即宇宙中确实存在极其微弱的星际磁场，它们可能是早期宇宙遗留下的"原初磁场"。 通过在地球上模拟极端物理条件，得以验证宇宙尺度下的过程，这是理解高能天体喷流及磁场起源的重 要一步。 宇宙早期极为均匀，磁场的种子机制仍不明确，可能涉及超越标准模型的新物理。未来 ...