排序方式: 共有19条查询结果,搜索用时 15 毫秒
11.
12.
Based on the branching fractions of J/ψ→VP from different experiments, we investigate the properties of the coupling constants of J/ψ→VP decays using a model-dependent approach. We find that the octet coupling constant, g8, of strong interaction is about twice larger than that of the singlet coupling constant g1; the electromag- netic breaking parameters gEi are larger than the mass breaking parameters gMi, moreover, the three parameters of the electromagnetic effect are about equal, but the three parameters of the mass effect are obviously different and their uncertainties are also large; and the phase angle between strong and electromagnetic interactions is in the range of 70°-80°. It deepens our understanding of the coupling constant of J/ψ→VP decays. 相似文献
13.
14.
15.
16.
17.
18.
19.
设计实现了一种晶圆级封装的三位MEMS数控衰减器,工作频段DC~15 GHz,衰减范围0~35 dB,步进5 dB。衰减器采用MEMS工艺实现,信号传输采用共面波导(CPW)结构,6个直接接触式悬臂梁MEMS开关对称放置实现不同衰减量的切换,每个开关带有三个触点,电阻网络采用T型结构,整个衰减器实现晶圆级封装。测试结果显示,DC~15 GHz频段内实现了8个衰减态,衰减器插入损耗小于1.7 dB,回波损耗小于-15 dB,衰减平坦度小于±5%,功耗几乎为零。芯片尺寸为2.7 mm×2.7 mm×0.8 mm。 相似文献