Search for supersymmetry with gauge-mediated breaking in diphoton events with missing transverse energy at CDF II.
Phys Rev Lett 104:1 (2010) 011801
Abstract:
We present the results of a search for supersymmetry with gauge-mediated breaking and chi(1)(0) --> gammaG in the gammagamma + missing transverse energy final state. In 2.6+/-0.2 fb(-1) of pp collisions at square root(s) = 1.96 TeV recorded by the CDF II detector we observe no candidate events, consistent with a standard model background expectation of 1.4+/-0.4 events. We set limits on the cross section at the 95% C.L. and place the world's best limit of 149 GeV/c2 on the chi(1)(0) mass at tau(chi(1)(0)) << 1 ns. We also exclude regions in the chi(1)(0) mass-lifetime plane for tau(chi(1)(0)) approximately < 2 ns.Flavor physics in the quark sector
Physics Reports 494:3-4 (2010) 197-414
Abstract:
In the past decade, one of the major challenges of particle physics has been to gain an in-depth understanding of the role of quark flavor. In this time frame, measurements and the theoretical interpretation of their results have advanced tremendously. A much broader understanding of flavor particles has been achieved; apart from their masses and quantum numbers, there now exist detailed measurements of the characteristics of their interactions allowing stringent tests of Standard Model predictions. Among the most interesting phenomena of flavor physics is the violation of the CP symmetry that has been subtle and difficult to explore. In the past, observations of CP violation were confined to neutral . K mesons, but since the early 1990s, a large number of CP-violating processes have been studied in detail in neutral . B mesons. In parallel, measurements of the couplings of the heavy quarks and the dynamics for their decays in large samples of . K,D, and . B mesons have been greatly improved in accuracy and the results are being used as probes in the search for deviations from the Standard Model.In the near future, there will be a transition from the current to a new generation of experiments; thus a review of the status of quark flavor physics is timely. This report is the result of the work of physicists attending the 5th CKM workshop, hosted by the University of Rome "La Sapienza", September 9-13, 2008. It summarizes the results of the current generation of experiments that are about to be completed and it confronts these results with the theoretical understanding of the field which has greatly improved in the past decade. © 2010 Elsevier B.V.HEAVY FLAVOR PHYSICS : LIFETIMES and FLAVOR CHANGING NEUTRAL CURRENTS
Proceedings of the 45th Rencontres de Moriond - 2010 Electroweak Interactions and Unified Theories, EW 2010 (2010) 313-318
Abstract:
The Tevatron, with pp collisions at p s =1.96 TeV, can produce all avors of B hadrons and allows for unprecedented studies in the B physics sector. These range from measurements of B hadron properties to searches of new physics signatures. The CDF 1 and D0 2 detectors currently have more than 7 fb-1 of data recorded. This paper presents a selection of recent results on lifetimes and avor changing neutral currents using between 4.3-5.0 fb-1 of data.Measurements of CP-conserving trilinear gauge boson couplings WWV (V ≡ γ, Z) in e+e- collisions at LEP2
European Physical Journal C 66:1 (2010) 35-56
Abstract:
The data taken by Delphi at centre-of-mass energies between 189 and 209 GeV are used to place limits on the CP-conserving trilinear gauge boson couplings Δ gZ1, λγ and Δκγ associated to W+W- and single W production at Lep2. Using data from the jjℓν, jjjj, jjX and ℓX final states, where j, ℓ and X represent a jet, a lepton and missing four-momentum, respectively, the following limits are set on the couplings when one parameter is allowed to vary and the others are set to their Standard Model values of zero: Results are also presented when two or three parameters are allowed to vary. All observations are consistent with the predictions of the Standard Model and supersede the previous results on these gauge coupling parameters published by Delphi. © © Springer-Verlag / Società Italiana di Fisica 2010.Prompt KS 0 production in pp collisions at s=0.9 TeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 693:2 (2010) 69-80