CP asymmetries at D0

Using two independent measurements of the semileptonic CP asymmetry in the $B_s$ system, we constrain the CP violating phase of the $B_s$ system to be $\phi_s = -0.70^{+0.47}_{-0.39}$. The data sample corresponds to an integrated luminosity of 1.1 fb$^{-1}$ accumulated with D0 detector at the Fermilab Tevatron collider. We also measure the direct CP violating asymmetry in the decay $B^+ \to J/\psi K^+$ to be $A_{CP}(B^+ \to J/\psi K^+) = +0.0067 \pm 0.0074$(stat)$\pm0.0026$(syst). The data corresponds to an integrated luminosity of 1.6 fb$^{-1}$.Comment: contributed paper to EPS07, Manchester, UK, manuscript number EPSHEPP17

Measurement of the W boson mass with 4.3 fb^-1 of D0 Run II data

A measurement of the W boson mass using 4.3 fb^-1 of integrated luminosity collected with the D0 detector during Run II of the Fermilab Tevatron collider is presented. Based on a sample of 1.68 * 10^6 W->enu candidate events, the W boson mass is measured to be M_W = 80.367 +/- 0.026 GeV. Combining this result with an earlier D0 result determined using an independent Run II data sample of 1 fb^-1 of integrated luminosity, yields M_W = 80.375 +/- 0.023 GeV.Comment: 8 pages, 7 figures, proceedings for Moriond EW 201

Search for new particles at CDFII

We report on the first results from the CDF experiment on search for physics beyond the Standard Model using data from the upgraded TeVatron collider running $p\bar p$ collisions at $\sqrt{s}$ = 1960 GeV. These first results, although obtained with a total integrated luminosity lower than the total integrated luminosity collected during Run I, are already competitive if not better, due to the increase in the center of mass energy and the improved detector capability.Comment: writeup of the talk given at XXXVIIIth Rencontres de Moriond on Electroweak Interactions and Unified Theories, Les Arcs March 200

LHC Higgs Production and Decay in the T' Model

At $\sqrt{s} = 7$ TeV, the standard model needs at least $10\, (fb)^{-1}$ integrated luminosity at LHC to make a definitive discovery of the Higgs boson. Using binary tetrahedral ($T^{'}$) discrete flavor symmetry, we discuss how the decay of the lightest $T'$ Higgs into $\gamma\,\gamma$ can be effectively enhanced and dominate over its decay into $b \, \bar{b}$. Since the two-photon final state allows for a clean reconstruction, a decisive Higgs discovery may be possible at 7 TeV with the integrated luminosity only of $\sim 1\, (fb)^{-1}$.Comment: 17 pages, 9 figure

Prompt and non-prompt J/ψ production in pp collisions at √s =7 TeV

The production of J/ψ mesons is studied in pp collisions at √s = 7 TeV with the CMS experiment at the LHC. The measurement is based on a dimuon sample corresponding to an integrated luminosity of 314 nb^(−1). The J/ψ differential cross section is determined, as a function of the J/ψ transverse momentum, in three rapidity ranges. A fit to the decay length distribution is used to separate the prompt from the non-prompt (b hadron to J/ψ) component. Integrated over J/ψ transverse momentum from 6.5 to 30 GeV/c and over rapidity in the range |y|<2.4, the measured cross sections, times the dimuon decay branching fraction, are 70.9±2.1(stat.)±3.0(syst.)±7.8(luminosity) nb for prompt J/ψ mesons assuming unpolarized production and 26.0±1.4(stat.)±1.6(syst.)±2.9(luminosity) nb for J/ψ mesons from b-hadron decays