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最近,在布鲁克海文国立实验室(BNL)和哈佛大学的实验证明,当高能质子束通过液体介质时能产生可探测到的声信号。观测到的声波与热膨胀模型预期的一致。结果表明,提出的另外两种发声机制,即:微气泡破裂及分子离解都没有任何有意义的贡献。我们研究了声波的频率和振幅分布、辐射图形,以及与温度、压力和介质的依赖关系。我们认为这个现象直接可用于束流的监测和高能重离子的探测。信号的阈值可能很低,或许可探测到(如下一代高能加速器产生的或来自高能宇宙线的)单个粒子所产生的粒子簇射。由于换能器成本低廉及声波在液体中传播较远,所以建造质量比目前使用的探测器大许多数量级的高能粒子探测器是有可能实现的。
Recently, experiments at Brockhead National Laboratory (BNL) and Harvard University have shown that a high-energy proton beam can produce a detectable acoustic signal as it passes through a liquid medium. The observed acoustic waves are in agreement with the thermal expansion model. The results show that the proposed two other sounding mechanisms, namely: microbubble rupture and molecular dissociation are not any meaningful contribution. We studied the frequency and amplitude distribution of sound waves, their radiation patterns, and their dependence on temperature, pressure and medium. We think this phenomenon can be directly used for beam monitoring and detection of high energy heavy ions. The threshold of the signal may be low, and it may be possible to detect a particle shower from a single particle (as produced by a next-generation high-energy accelerator or from a high-energy cosmic ray). Due to the low cost of transducers and the propagation of sound waves in the liquid, it is possible to build high-energy particle detectors of much greater order of magnitude than the currently used detectors.