On this day, 38 years ago, on December 7, 1987 (October 17, 1987, the lunar calendar), my country accelerated electron energy to gigahertz electron volts for the first time. In early December 1987, the electron linac in the Beijing Electron Positron Collider Project accelerated electron energy to gigaelectronvolts for the first time. This energy was not only the highest in China at that time, but also not much among similar accelerators in the world. The more than 200-meter-long electron linear accelerator is one of the four major components of the Beijing Electron-Positron Collider. In May of this year, researchers used this accelerator to accelerate electrons to an energy of 250 MeV and a current intensity of 750 milliamps. Over the past few months, after further installation and debugging, electrons have been accelerated to 1100 MeV and an electron beam current with a current intensity of 200 mA, thus initially reaching the design specifications and laying the foundation for my country to carry out high-energy physics research and synchrotron radiation optical application research. The first cornerstone.