The focus of this report is the lattice calculation of hadronic parameters relevant to heavy flavour phenomenology. I will review recent results and the current status of studies of the B and D decay constants, semileptonic decay form factors, B 0 − ¯B 0 mixing, and determinations of the quark masses mc and mb. Some studies of heavy flavour observables have used current lattice results to derive Standard Model predictions that disagree with experimental measurements. That is the case of sin(2β) and fDs. This report discusses efforts to resolve the origin of those discrepancies from the lattice side.

Abstract: Assuming there is a new gauge group in a Hidden Valley, and a new type of radiation, can we observe it through its effect on the kinematic distributions of recoiling visible particles? Specifically, what are the collider signatures of radiation in a hidden sector? We address these questions using a generic SU(N)-like Hidden Valley model that we implement in Pythia. We find that in both the e + e − and the LHC cases the kinematic distributions of the visible particles can be significantly affected by the valley radiation. Without a proper understanding of such effects, inferred masses of “communicators ” and

As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Jeffrey Willard Temple entitled “Measurement of mtop via Neutrino Weighting in the Dilepton Decay Channels at DØ ” and recommend that it be accepted as fulfilling

I give an introduction to the theory of meson-antimeson mixing, aiming at students who plan to work at a flavour physics experiment or intend to do associated theoretical studies. I derive the formulae for the time evolution of a neutral meson system and show how the mass and width differences among the neutral meson eigenstates and the CP phase in mixing are calculated in the Standard Model. Special emphasis is laid on CP violation, which is covered in detail for K−K mixing, Bd−Bd mixing and Bs−Bs mixing. I explain the constraints on the apex (ρ, η) of the unitarity triangle implied by ǫK, ∆MB d, ∆MB d /∆MBs and various mixing-induced CP asymmetries such as aCP(Bd → J/ψKshort)(t). The impact of a future measurement of CP violation in flavour-specific Bd decays is also shown. 1 First lecture: A big-brush picture 1.1 Mesons, quarks and box diagrams The neutral K, D, Bd and Bs mesons are the only hadrons which mix with their antiparticles. These meson states are flavour eigenstates and the corresponding antimesons K, D, Bd and Bs have opposite flavour quantum numbers:

The decay b → sν¯ν is discussed in the minimal supersymmetric standard model with general flavor mixing for squarks, at large tanβ. In this case, in addition to the chargino loop contributions which were analyzed in previously studies, tan β-enhanced contributions from the gluino and charged Higgs boson loops might become sizable compared with the standard model contribution, at least in principle. However, it is demonstrated that the experimental bounds on the new physics contributions to the radiative decay b → sγ should strongly constrain these contributions to b → sν¯ν, especially on the gluino contribution. A possible constraint from the Bs → µ + µ − decay is also briefly commented. PACS: 13.20.He, 12.60.Jv 1 1

Over the last years the Tevatron Run-II has extended several limits on Higgs boson masses and coupling which were pioneered during the LEP accelerator operation between 1989 and 2000. Higgs boson searches will also be at the forefront of research at the LHC. This review concisely discusses the experimental constraints set by the CDF and DØ collaborations in winter 2008/2009 at the beginning of the LHC era. Model-independent and modeldependent limits on Higgs boson masses and couplings have been set and interpretations are discussed both in the Standard Model and in extended models. Recently, for the first time the Tevatron excludes a SM Higgs boson mass range (160-170 GeV) beyond the LEP limit at 95 % CL. The experimental sensitivities are estimated for the completion of the Tevatron programme.

We have investigated the possibility of direct tests of little Higgs models incorporating triplet Higgs neutrino mass mechanism at LHC experiments. We have performed Monte Carlo studies of Drell-Yan pair production of doubly charged Higgs boson Φ ++ followed by its leptonic decays whose branching ratios are fixed from the neutrino oscillation data. We propose appropriate selection rules for the four-lepton signal, including reconstructed taus, which are optimized for the discovery of Φ ++ with the lowest LHC luminosity. As the Standard Model background can be effectively eliminated, an important aspect of our study is the correct statistical treatment of the LHC discovery potential. Adding detection efficiencies and measurement errors to the Monte Carlo analyses, Φ ++ can be discovered up to the mass 250 GeV in the first year of LHC, and 700 GeV mass is reachable for the integrated luminosity L = 30 fb −1. The main motivation of the Large Hadron Collider (LHC) experiment is to reveal the secrets of electroweak symmetry breaking. If the light standard model (SM) Higgs boson H will be discovered, the question arises what stabilizes its mass against the Planck scale quadratically

Fermilab operates the world’s most intense antiproton source, now exclusively dedicated to serving the needs of the Tevatron Collider. The anticipated 2009 shutdown of the Tevatron presents the opportunity for a world-leading low- and medium-energy antiproton program. We summarize the status of the Fermilab antiproton facility and review physics topics for which a future experiment could make the world’s best measurements.

Dijet cross sections as functions of several jet observables are measured in photoproduction using the H1 detector at HERA. The data sample comprises e p data with an integrated luminosity of 34.9 pb -1 . Jets are selected using the inclusive k algorithm with a minimum transverse energy of 25 GeV for the leading jet. The phase space covers longitudinal proton momentum fraction x p and photon longitudinal momentum fraction x # in the ranges 0.05 p 0.6 and 0.1 # 1. The predictions of next-to-leading order perturbative QCD, including recent photon and proton parton densities, are found to be compatible with the data in a wide kinematical range.

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