Ghilea M C, Meyerhofer D D, Sangster T C
Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299, USA.
Rev Sci Instrum. 2011 Mar;82(3):033305. doi: 10.1063/1.3554649.
Neutron imaging is one of the main methods used in inertial confinement fusion experiments to measure the core symmetry of target implosions. Previous studies have shown that bubble chambers have the potential to obtain higher resolution images of the targets for a shorter source-to-target distance than typical scintillator arrays. A bubble chamber for neutron imaging with Freon 115 as the active medium was designed and built for the OMEGA laser system. Bubbles resulting from spontaneous nucleation were recorded. Bubbles resulting from neutron-Freon interactions were observed at neutron yields of 10(13) emitted from deuterium-tritium target implosions on OMEGA. The measured column bubble density was too low for neutron imaging on OMEGA but agreed with the model of bubble formation. The recorded data suggest that neutron bubble detectors are a promising technology for the higher neutron yields expected at National Ignition Facility.
中子成像技术是惯性约束聚变实验中用于测量靶丸内爆核心对称性的主要方法之一。此前的研究表明，与典型的闪烁体阵列相比，气泡室在源到靶距离较短的情况下，有潜力获得更高分辨率的靶丸图像。为欧米伽激光系统设计并建造了一个以氟利昂115作为活性介质的用于中子成像的气泡室。记录了自发成核产生的气泡。在欧米伽上氘 - 氚靶丸内爆产生10(13)的中子产额时，观察到了中子与氟利昂相互作用产生的气泡。对于欧米伽上的中子成像而言，所测量的柱状气泡密度过低，但与气泡形成模型相符。记录的数据表明，对于国家点火装置预期的更高中子产额，中子气泡探测器是一项很有前景的技术。
