Limits on anomalous trilinear gauge couplings in Zγ events from pp̄ collisions at √s=1.96TeV
Physical Review Letters 107:5 (2011)
Abstract:
Using Zγ candidate events collected by the CDF detector at the Tevatron Collider, we search for potential anomalous (non-standard-model) couplings between the Z boson and the photon. Zγ couplings vanish at tree level and are heavily suppressed at higher orders; hence any evidence of couplings indicates new physics. Measurements are performed using data corresponding to an integrated luminosity of 4.9fb-1 in the Z→νν̄ decay channel and 5.1fb-1 in the Z→l +l- (l=μ, e) decay channels. The combination of these measurements provides the most stringent limits to date on Zγ trilinear gauge couplings. Using an energy scale of Λ=1.5TeV to allow for a direct comparison with previous measurements, we find limits on the CP-conserving parameters that describe Zγ couplings to be |h3γ,Z|<0.022 and |h4γ,Z|<0.0009. These results are consistent with standard model predictions. © 2011 American Physical Society.First search for multijet resonances in √s=1.96TeV pp̄ collisions
Physical Review Letters 107:4 (2011)
Abstract:
We present the first model independent search for three-jet hadronic resonances within multijet events in √s=1.96TeV pp̄ collisions at the Fermilab Tevatron using the CDF II detector. Pair production of supersymmetric gluinos and squarks with hadronic R-parity violating decays is employed as an example of a new physics benchmark for this signature. Selection criteria based on the kinematic properties of an ensemble of jet combinations within each event help to extract signal from copious QCD background. No significant excess outside the top quark mass window is observed in data with an integrated luminosity of 3.2fb⊃-1. We place 95% confidence level limits on the production cross section σ(pp̄→XX⊃′) ×BR(gg→3jet+3jet) where X, X⊃′=g, q, or q̄, with q, q̄→g+jet, as a function of gluino mass, in the range of 77GeV/c2 to 240GeV/c2. © 2011 American Physical Society.Measurements of the properties of Λc (2595), Λc (2625), Σc (2455), and Σ c (2520) baryons
Physical Review D - Particles, Fields, Gravitation and Cosmology 84:1 (2011)
Abstract:
We report measurements of the resonance properties of Λ c(2595)+ and Λc(2625)+ baryons in their decays to Λc+π+π- as well as Σc(2455)++,0 and Σ c(2520)++,0 baryons in their decays to Λc+π± final states. These measurements are performed using data corresponding to 5.2fb-1 of integrated luminosity from pp̄ collisions at √s=1.96TeV, collected with the CDF II detector at the Fermilab Tevatron. Exploiting the largest available charmed baryon sample, we measure masses and decay widths with uncertainties comparable to the world averages for Σc states, and significantly smaller uncertainties than the world averages for excited Λc+ states. © 2011 American Physical Society.Measurements of the properties of Λc(2595), Λc(2625), Σc(2455), and Σc(2520) baryons
Physical Review D American Physical Society (APS) 84:1 (2011) 012003
First search for multijet resonances in sqrt(s) = 1.96 TeV pp collisions.
Physical review letters 107:4 (2011) 042001