Study of Supersymmetry at Experiments with the Highest Energy Proton-proton Collider

超对称性理论是粒子物理学标准模型之外最有前途的理论，为了验证它，必须在高能粒子对撞机上直接产生超对称粒子，以获得它的直接证据。欧洲核子研究中心正在建造的大型强子对撞机（LHC）就是这样一台质子-质子对撞机，对撞能量为14 TeV。大型强子对撞机将于2007年底建成并开始运行，预计在其启动后的几年内将发现超对称粒子。然而，由于LHC的超对称性事件具有长的级联衰变链和巨大的背景事件，因此将是非常复杂的。因此，在启动LHC pp碰撞实验的物理运行之前，需要做好充分的准备。利用该资助，我们打算在高能物理领域的实验物理学家和理论物理学家的合作下，在LHC上进行超对称性的物理研究，并明确在LHC上可以研究什么和如何研究超对称性。主要研究结果如下：1.在CERN LHC 2上对第三代夸克的详细研究。在CERN LHC 3上用非指向光子研究规范中介信号。在CERN LHC 4上研究斯莱普顿非普适性。CERN LHC 5的新超对称重建方法。LHC和ILC 6的物理相互作用。在CERN LHC 7的MSSM中约束暗物质。用简并质谱发现超对称性

In order to verify supersymmetry, (SUSY), the most promising theory beyond the standard model of particle physics, it is necessary to obtain its direct evidence by directly producing SUSY particles at high energy particle colliders. At the Large Hadron Collider (LHC), being constructed at CERN, is such a collider for proton-proton collision with the colliding energy of 14 TeV. The LHC will be completed and start its operation by the end of year 2007, and discovery of SUSY particles is expected within a few years from its start. However, the SUSY events at the LHC will be very complicated because of their long cascade decay chains and tremendous background events. Therefore we need to be well prepared before starting the physics run of the pp collision experiments at the LHC.With this grant-in-aid we intend to perform physics studies on the SUSY at the LHC, with a cooperative work among experimental and theoretical physicists in the field of high energy physics, and to clarify what and how we can study SUSY at the LHC. The main results we have obtained are Listed as follows.1. Detailed study of third generation squarks at the CERN LHC2. Study of the gauge mediation signal with non-pointing photons at the CERN LHC3. Study of the slepton non-universality ath the CERN LHC4. New supersymmetry reconstruction method at the CERN LHC5. Physics interplay of the LHC and ILC6. Constraining dark matter in the MSSM at the CERN LHC7. Discovery of supersymmetry with degenerate mass spectrum