Division of High Energy Physics, Department of Physics, University of Helsinki and Helsinki Institute of Physics, FIN-00014, Helsinki, Finland.
Phys Rev Lett. 2012 May 18;108(20):201802. doi: 10.1103/PhysRevLett.108.201802. Epub 2012 May 15.
We report a new search for dark matter in a data sample of an integrated luminosity of 7.7 fb-1 of Tevatron pp[over ¯] collisions at √[s]=1.96 TeV, collected by the CDF II detector. We search for production of a dark-matter candidate, D, in association with a single top quark. We consider the hadronic decay mode of the top quark exclusively, yielding a final state of three jets with missing transverse energy. The data are consistent with the standard model; we thus set 95% confidence level upper limits on the cross section of the process pp[over ¯]→t+D as a function of the mass of the dark-matter candidate. The limits are approximately 0.5 pb for a dark-matter particle with mass in the range of 0-150 GeV/c2.
我们报告了在一个由 CDF II 探测器收集的 7.7 fb-1 的 Tevatron pp[over ¯]碰撞的积分亮度数据样本中,对暗物质的新搜索。我们在单个顶夸克的伴随下,寻找暗物质候选体 D 的产生。我们只考虑顶夸克的强子衰变模式,得到一个带有横向能量缺失的三个喷注的末态。数据与标准模型一致;因此,我们对 pp[over ¯]→t+D 过程的截面在暗物质候选体质量范围内设定了 95%置信水平的上限。对于质量在 0-150 GeV/c2 范围内的暗物质粒子,限制大约为 0.5 pb。