Chang Jun Gao^1,* and Shuang Nan Zhang^1,2,3,4,†

• ¹Department of Physics and Center for Astrophysics, Tsinghua University, Beijing 100084, China‡
• ²Physics Department, University of Alabama, Huntsville, Alabama 35899, USA
• ³Space Science Laboratory, NASA Marshall Space Flight Center, SD50, Huntsville, Alabama 35812, USA
• ⁴Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039, China

• ^*Email address: gaocj@mail.tsinghua.edu.cn
• ^†Email address: zhangsn@mail.tsinghua.edu.cn
• ^‡Mailing address.