Quark and lepton masses from top loops

Assuming that the leptons and quarks other than top are massless at tree level, we show that their masses may be induced by loops involving the top quark. As a result, the generic features of the fermion mass spectrum arise from combinations of loop factors. Explicitly, we construct a renormalizable model involving a few new particles, which leads to 1-loop bottom and tau masses, a 2-loop charm mass, 3-loop muon and strange masses, and 4-loop masses for first generation fermions. This realistic pattern of masses does not require any symmetry to differentiate the three generations of fermions. The new particles may produce observable effects in future experiments searching for mu to e conversion in nuclei, rare meson decays, and other processes.Comment: 29 pages; Introduction expanded, references adde

Improved method for aerodynamic analysis of wing-body-tail configurations in subsonic and supersonic flow

Method permits analysis of noncircular bodies and calculation of wing-body interference effects in presence of body closure, two features not previously available. In addition, use of vortex distribution, having linear variation in streamwise direction, results in improved chordwise pressure distributions on wing and tail surfaces

CP violation in B_s mixing from heavy Higgs exchange

The anomalous dimuon charge asymmetry reported by the D0 Collaboration may be due to the tree-level exchange of some spin-0 particles that mediate CP violation in B_s-\bar{B}_s meson mixing. We show that for a range of couplings and masses, the heavy neutral states in a two Higgs doublet model can generate a large charge asymmetry. This range is natural in "uplifted supersymmetry", and may enhance the B^- -> tau nu and B_s -> mu^+ mu^- decay rates. However, we point out that on general grounds the reported central value of the charge asymmetry requires new physics not only in B_s-\bar{B}_s mixing but also in \Delta B = 1 transitions or in B_d-\bar{B}_d mixing.Comment: 5 pages, 1 figure. v2: Equations (17)-(19) included to clarify the flavor structure of uplifted supersymmetr

Higgs-photon resonances

We study models that produce a Higgs boson plus photon ($h^0 \gamma$) resonance at the LHC. When the resonance is a $Z'$ boson, decays to $h^0 \gamma$ occur at one loop. If the $Z'$ boson couples at tree-level to quarks, then the $h^0 \gamma$ branching fraction is typically of order $10^{-5}$ or smaller. Nevertheless, there are models that would allow the observation of $Z' \to h^0 \gamma$ at $\sqrt{s} = 13$ TeV with a cross section times branching fraction larger than 1 fb for a $Z'$ mass in the 200--450 GeV range, and larger than 0.1 fb for a mass up to 800 GeV. The 1-loop decay of the $Z'$ into lepton pairs competes with $h^0 \gamma$, even if the $Z'$ couplings to leptons vanish at tree level. We also present a model in which a $Z'$ boson decays into a Higgs boson and a pair of collimated photons, mimicking an $h^0 \gamma$ resonance. In this model, the $h^0 \gamma$ resonance search would be the discovery mode for a $Z'$ as heavy as 2 TeV. When the resonance is a scalar, although decay to $h^0 \gamma$ is forbidden by angular momentum conservation, the $h^0$ plus collimated photons channel is allowed. We comment on prospects of observing an $h^0 \gamma$ resonance through different Higgs decays, on constraints from related searches, and on models where $h^0$ is replaced by a nonstandard Higgs boson.Comment: 22 page

A Green's function formulation for a nonlinear potential flow solution applicable to transonic flow

Routine determination of inviscid subsonic flow fields about wing-body-tail configurations employing a Green's function approach for numerical solution of the perturbation velocity potential equation is successfully extended into the high subsonic subcritical flow regime and into the shock-free supersonic flow regime. A modified Green's function formulation, valid throughout a range of Mach numbers including transonic, that takes an explicit accounting of the intrinsic nonlinearity in the parent governing partial differential equations is developed. Some considerations pertinent to flow field predictions in the transonic flow regime are discussed