Measurement of the tt̄ production cross section in pp̄ collisions at √s=1:96 TeV using kinematic fitting of b-tagged lepton+jet events
Physical Review D Particles Fields Gravitation and Cosmology 71:7 (2005) 1-11
Abstract:
We report a measurement of the tt̄ production cross section using the CDF II detector at the Fermilab Tevatron. The data consist of events with an energetic electron or muon, missing transverse energy, and three or more hadronic jets, at least one of which is identified as a b-quark jet by reconstructing a secondary vertex. The background fraction is determined from a fit of the transverse energy of the leading jet. Using 162 ± 10 pb -1 of data, the total cross section is found to be 6.0 ± 1.6(stat.) ± 1.2(syst.) pb, which is consistent with the standard model prediction. © 2005 The American Physical Society.Search for η(1475)→KS0K±π∓ in two-photon fusion at the CLEO detector at Cornell
Physical Review D American Physical Society (APS) 71:7 (2005) 072001
Radiation-hard semiconductor detectors for SuperLHC
Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment Elsevier 541:1-2 (2005) 189-201
Pseudo-Goldstones from Supersymmetric Wilson Lines on 5D Orbifolds
ArXiv hep-ph/0503255 (2005)
Abstract:
We consider a U(1) gauge theory on the five dimensional orbifold $\mathcal{M}_4\times S^1/Z_2$, where $A_5$ has even $Z_2$ parity. This leads to a light pseudoscalar degree of freedom $W(x)$ in the effective 4D theory below the compactification scale arising from a gauge-invariant brane-to-brane Wilson line. As noted by Arkani-Hamed et al in the non-supersymmetric $S^1$ case the 5D bulk gauge-invariance of the underlying theory together with the non-local nature of the Wilson line field leads to the protection of the 4D theory of $W(x)$ from possible large global-symmetry violating quantum gravitational effects. We study the $S^1/Z_2$ theory in detail, in particular developing the supersymmetric generalization of this construction, involving a pseudoscalar Goldstone field (the `axion') and its scalar and fermion superpartners (`saxion' and `axino'). The global nature of $W(x)$ implies the absence of independent Kaluza-Klein excitations of its component fields. The non-derivative interactions of the (supersymmetric) Wilson line in the effective 4D theory arising from U(1) charged 5D fields $\Phi$ propagating between the boundary branes are studied. We show that, similar to the non-supersymmetric $S^1$ case, these interactions are suppressed by $\exp(-\pi R m_{\Phi})$ where $\pi R$ is the size of the extra dimension.Pseudo-Goldstones from Supersymmetric Wilson Lines on 5D Orbifolds
(2005)