Search for the Rare Decays KL->pi0pi0mu+mu- and KL->pi0pi0X0->pi0pi0mu+mu-
KTeV Collaboration, E. Abouzaid, M. Arenton, A. R. Barker, L. Bellantoni, E. Blucher, G. J. Bock, E. Cheu, R. Coleman, M. D. Corcoran, B. Cox, A. R. Erwin, C. O… 展开作者
KTeV Collaboration, E. Abouzaid, M. Arenton, A. R. Barker, L. Bellantoni, E. Blucher, G. J. Bock, E. Cheu, R. Coleman, M. D. Corcoran, B. Cox, A. R. Erwin, C. O. Escobar, A. Glazov, A. Golossanov, R. A. Gomes, P. Gouffon, Y. B. Hsiung, D. A. Jensen, R. Kessler, K. Kotera, A. Ledovskoy, P. L. McBride, E. Monnier, H. Nguyen, R. Niclasen, D. G. Phillips, H. Ping, E. J. Ramberg, R. E. Ray, M. Ronquest, E. Santos, W. Slater, D. Smith, N. Solomey, E. C. Swallow, P. A. Toale, R. Tschirhart, C. Velissaris, Y. W. Wah, J. Wang, H. B. White, J. Whitmore, M. J. Wilking, R. Winston, E. T. Worcester, M. Worcester, T. Yamanaka, E. D. Zimmerman, R. F. Zukanovich
KTeV E799实验已经对稀有衰变KL-> pi 0 pi 0 mu +mu-和KL-> pi 0 pi 0X 0-> pi 0 pi 0 mu +mu-进行了搜索，其中X 0是HyperCP实验报告的可能的新中性玻色子，质量为（214.3 pm 0.5）MeV/c^{2}。我们找不到任何一种衰变的证据。在90%置信水平下，我们得到Br（KL-> pi 0 pi 0X 0-> pi 0 pi 0 mu +mu-）< 1.0 x 10^{-10}和Br（KL-> pi 0 pi 0 mu +mu-）< 9.2 x 10^{-11}的上限。在\bar{d} sX 0耦合完全真实的情况下，该结果排除了作为HyperCP结果的解释的伪标量X 0。
英文摘要：
The KTeV E799 experiment has conducted a search for the rare decays KL->pi0pi0mu+mu- and KL->pi0pi0X0->pi0pi0mu+mu-, where the X0 is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 pm 0.5) MeV/c^{2}. We find no evidence for either decay. We obtain upper limits of Br(KL->pi0pi0X0->pi0pi0mu+mu-) < 1.0 x 10^{-10} and Br(KL->pi0pi0mu+mu-) < 9.2 x 10^{-11} at the 90% confidence level. This result rules out the pseudoscalar X0 as an explanation of the HyperCP result under the scenario that the \bar{d}sX0 coupling is completely real.
An Expression of Interest to Detect and Measure the Dierct CP Violating Decay K_L --> pi0 nu nu_bar and Other Rare Decays at Fermilab Using the Main Injector
我们，KAMI（主注入器的K介子）合作，表示我们有兴趣继续在费米实验室使用主注入器的稀有K介子衰变物理实验计划。KAMI的主要物理学目标是：1。第一次探测到罕见的直接CP破坏衰变K_L --> pi 0 nu nu_bar，并以10%的精度测量其分支比，对应于以5%的精度测量CP破坏参数eta;以及2.研究了其它各种稀有衰变过程，如K_L ~-、pi 0 ee、pi 0 mumu、pi 0 mue、pi+pi-e+e ~-、mu+mu ~-、e+e ~-等，灵敏度约为10 E ~（-13）。
