123177090
Two-dimensional Lorentz-violating Chern-Simons-like action
Abstract We demonstrate generation of the two-dimensional Chern–Simons-like Lorentz-breaking action via an appropriate Lorentz-breaking coupling of scalar and spinor fields at zero as well as at the finite temperature and via the noncommutative fields method and study the dispersion relations corresponding to this action.
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.
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.
118338237
Supersymmetric extensions of k-field models
Abstract We investigate the supersymmetric extension of k-field models, in which the scalar field is described by generalized dynamics. We illustrate some results with models that support static solutions with the standard kink or the compact profile.
2496873
Complete low-energy effective action in N=4 SYM: A Direct N=2 supergraph calculation
Using the covariant N=2 harmonic supergraph techniques we calculate the one-loop low-energy effective action of N=4 super-Yang–Mills theory in Coulomb branch with gauge group SU(2) spontaneously broken down to U(1). The full dependence of the low-energy effective action on both the hypermultiplet and gauge fields is determined. The direct quantum calculation confirms the correctness of the exact N=4 SYM low-energy effective action derived in hep-th/0111062 on the purely algebraic ground by invoking a hidden N=2 supersymmetry which completes the manifest N=2 one to N=4. Our results provide an exhaustive solution to the problem of finding out the exact completely N=4 supersymmetric low-energy effective action for the theory under consideration.
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.
9264360
Mixing and CP-violation in charm
The motivation most often cited in searches for D 0 − D 0 ¯ mixing and CP-violation in charm system lies with the possibility of observing a signal from new physics which dominates that from the Standard Model. We review recent theoretical predictions and experimental constraints on D 0 − D 0 ¯ mixing parameters. We also discuss the current status of searches for CP-violation in charmed meson transitions, as well as some recent theoretical ideas.
118689000
Searching for super-WIMPs in leptonic heavy meson decays
Abstract We study constraints on the models of bosonic super-weakly interacting particle (super-WIMP) dark matter (DM) with DM masses m X ∼ O ( 1 – 100 ) keV from leptonic decays M → l ν ¯ l + X , where M = B ± , D ± , D s ± is a heavy meson state. We focus on two cases where X denotes either a light pseudoscalar (axion-like), or a light vector state that couples to the standard model (SM) through kinetic mixing. We note that for a small DM mass these decays are separately sensitive to DM couplings to quarks, but not its mass.
18254039
Comments on color-suppressed hadronic B decays
Abstract Recent experimental results on the color-suppressed nonleptonic decays B 0 →D (∗)0 π 0 provide evidence for a failure of the naive factorization model and for sizeable relative strong-interaction phases between class-1 and class-2 B →D (∗) π decay amplitudes. The allowed regions for the corresponding ratios of (complex) isospin amplitudes and a 2 / a 1 parameters are determined. The results are interpreted in the context of QCD factorization for the related class-1 amplitudes in the heavy-quark limit.
2033960
Intrinsic charm of light mesons and CP violation in heavy quark decay
We investigate the impact of the intrinsic heavy quark states on the predicted values of CP asymmetries in the decays of heavy mesons. It is shown that the intrinsic charm contribution, although dynamically suppressed in QCD, is favored by the weak interaction, and therefore it can significantly dilute the predicted values of CP-violating asymmetries. This introduces additional non-perturbative uncertainty into the estimate of direct CP violating effects.
53398529
Hunting for CP violation with untagged charm decays
We construct a CP-violating observable which does not require flavor or CP tagging of the initial state. The proposed decay asymmetry could be measured at both threshold and non-threshold charm physics experiments and provide better sensitivity to small CP-violating parameters in charm decays.