We describe an experiment to measure the electromagnetic analog of gravitational wave memory, the so-called electromagnetic (EM) memory. Whereas gravitational wave memory is a residual displacement of test masses, EM memory is a residual velocity (i.e. kick) of test charges. The source of gravitational wave memory is energy that is not confined to any bounded spatial region: in the case of binary black hole mergers the emitted energy of gravitational radiation as well as the recoil energy of the final black hole. Similarly, EM memory requires a source whose charges are not confined to any bounded spatial region. While particle beams can provide unbounded charges, their currents are too small to be practical for such an experiment. Instead we propose a short microwave pulse applied to the center of a long dipole antenna. In this way the measurement of the kick can be done quickly enough that the finite size of the antenna does not come into play and it acts for our purposes the same as if it were an infinite antenna.

中文翻译：

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测量电磁记忆的实验


我们描述了一个测量引力波记忆的电磁模拟的实验，即所谓的电磁 （EM） 记忆。引力波记忆是测试质量的残余位移，而电磁记忆是测试电荷的残余速度（即踢）。引力波记忆的来源是不局限于任何有界空间区域的能量：在双黑洞合并的情况下，引力辐射发射的能量以及最终黑洞的反冲能量。同样，EM 存储器需要一个电荷不局限于任何有界空间区域的源。虽然粒子束可以提供无界电荷，但它们的电流太小，无法用于此类实验。相反，我们建议将短微波脉冲施加到长偶极子天线的中心。通过这种方式，可以足够快地完成反冲的测量，以至于天线的有限尺寸不会起作用，并且它的作用与无限天线相同。