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

为了验证超对称理论（SUSY）这一粒子物理标准模型之外最有前途的理论，有必要通过在高能粒子对撞机上直接产生SUSY粒子来获得它的直接证据。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年底完工并开始运行，预计在其启动后的几年内将发现超对称性粒子。然而，由于其长级联衰变链和巨大的背景事件，大型强子对撞机的超对称性事件将非常复杂。因此，我们需要在大型强子对撞机开始pp碰撞实验的物理运行之前做好充分的准备。有了这笔资助，我们打算在高能物理领域的实验和理论物理学家的合作下，在大型强子对撞机上对超对称性进行物理研究，并阐明我们可以在大型强子对撞机上研究什么以及如何研究超对称性。我们得到的主要结果如下：第三代夸克在欧洲核子研究中心LHC2的详细研究。欧洲核子研究中心LHC3非指向光子规范中介信号的研究。欧洲核子研究中心LHC4的睡眠非普适性研究。欧洲核子研究中心LHC5的新超对称重建方法。LHC与ILC6的物理相互作用。在欧洲核子研究中心LHC7的MSSM中限制暗物质。发现具有简并质谱的超对称

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