118627259
On the perturbative generation of the higher-derivative Lorentz-breaking terms
In this paper, we describe the perturbative generation of the higher-derivative Lorentz-breaking terms for the gauge field, that is, the Myers-Pospelov term and the higher-derivative Carroll-Field-Jackiw term. These terms are explicitly calculated in the one-loop approximation and shown to be finite and ambiguous.
118435943
Equivalence between supersymmetric self-dual and Maxwell–Chern–Simons models coupled to a matter spinor superfield
Abstract We study the duality of the supersymmetric self-dual and Maxwell–Chern–Simons theories coupled to a fermionic matter superfield, using a master action. This approach evades the difficulties inherent to the quartic couplings that appear when matter is represented by a scalar superfield. The price is that the spinorial matter superfield represents a unusual supersymmetric multiplet, whose main physical properties we also discuss.
118455730
Effective potential for a SUSY Lee–Wick model: The Wess–Zumino case
Using a superfield generalization of the tadpole method, we study the one-loop effective potential for a Wess–Zumino model modified by a higher derivative term, inspired by the Lee–Wick model. The one-loop Kahlerian potential is also obtained by other methods and compared with the effective potential.
96444982
Horava-Lifshitz-like extensions of supersymmetric theories
Within the superfield approach, we formulate two different extensions of the Wess-Zumino model and super-QED with Horava-Lifshitz-like additive terms, discuss their quantum properties and calculate lower contributions to the effective action. In the case of the gauge theory, the one-loop effective potential turns out to be gauge independent.
118533824
Free energy of Lorentz-violating QED at high temperature
In this paper we study the one- and two-loop contribution to the free energy in QED with Lorentz symmetry breaking introduced via constant CPT-even Lorentz-breaking parameters at the high temperature limit. We find the impact of the Lorentz-violating term for the free energy and carry out a numerical estimation for the Lorentz-breaking parameter.
119211852
Lorentz violation and the proper-time method
Abstract In this Letter, we apply the proper-time method to generate the Lorentz-violating Chern–Simons terms in the four-dimensional Yang–Mills and non-linearized gravity theories. It is shown that the coefficient of the induced Chern–Simons term is finite but regularization dependent.
125948025
Eta-prime production in B decays: Standard model versus new physics
17373947
How to trap a non-standard penguin? Isospin symmetry violations in B-decays with enhanced chromomagnetic dipole operator
Abstract A recently proposed non-standard model solution to the problem of low semileptonic branching ratio B SL which suggests a large branching ratio for the decay b → sg is critically examined. It is shown that the effects of the enhanced chromomagnetic dipole operator might lead to significant violations of isospin symmetry in rate radiative decays of B -mesons.
14564633
CHARM MIXING IN THE STANDARD MODEL AND BEYOND
Quantum mechanical meson-antimeson oscillations are sensitive to heavy degrees of freedom which propagate in the underlying mixing amplitudes. Comparing observed meson mixing with predictions of the Standard Model (SM), modern experimental studies would be able to constrain models of New Physics (NP). Yet, extensive precission data from B-factories and the Tevatron collider show that the large SM mixing succesfully describes all available experimental data in Bd and Bs oscillations. The only flavor oscillation not yet observed is that of the charmed meson D, where SM mixing is very small and the NP component can stand out. This situation is an exact opposite to what happens in the B system, where B − B0 mixing measurements are used to constrain top quark couplings. Together with the one loop Standard Model effects NP effects can contribute to ∆C = 1 (decays) or ∆C = 2 (mixing) transitions. In the case of D −D0 mixing these operators generate contributions to the effective operators that change D state into D0 state, leading to the mass eigenstates |D1,2〉 = p|D〉 ± q|D〉, (1)
119248767
The flavor puzzle in multi-Higgs models
We reconsider the flavor problem in the models with two Higgs doublets. By studying two generation toy models, we look for flavor basis independent constraints on Yukawa couplings that will give us the mass hierarchy while keeping all Yukawa couplings of the same order. We then generalize our findings to the full three generation Standard Model. We find that we need two constraints on the Yukawa couplings to generate the observed mass hierarchy, and a slight tuning of Yukawa couplings of order 10%, much less than the Standard Model. We briefly study how these constraints can be realized, and show how flavor changing currents are under control for $ K - \bar{K} $ mixing in the neardecoupling limit.
119453062
Hybrid Charmonium Production in NRQCD
Using the operator product expansion and nonrelativistic QCD we study the production of charmonium hybrids in B decays. We express the decay rate in terms of a few matrix elements which eventually will be fixed by experimental measurements or calculated on the lattice. While the Fock state expansion is problematic for hybrids, the operator product expansion still provides a model independent framework for phenomenological calculations of hybrid production and decay. We then use a simple flux tube model to estimate the branching ratio B -> psi_g+X, where psi_g is a J^{PC}=0^{+-} hybrid, the large production of which could help resolve the low charm multiplicity observed in B decays.