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.
17946700
CP-violation in charm
I review recent results in theoretical and experimental analyses of CP-violation in charmed transitions, paying particular attention to constraints on parameters of beyond the Standard Model interactions.
118687281
Hadronic D and D(s) Meson Decays
We provide a comprehensive review of hadronic decays of D and D_s mesons. We discuss current theoretical and experimental challenges and successes in understanding of hadronic transitions of those mesons. A brief overview of the theoretical and experimental tools are given before discussing the absolute branching fractions for D and D_s mesons. Cabibbo suppressed and rare hadronic decays are discussed and compared with theory before discussing our understanding of hadronic multibody decays.
117901603
X(3872) in effective field theory
We consider the implications from the possibility that the recently observed state X(3872) is a meson‐antimeson molecule. We write an effective Lagrangian consistent with the heavy‐quark and chiral symmetries needed to describe X(3872) and study its properties.
35942201
Is B-->Xs gamma equal to b-->s gamma ? Spectator contributions to rare inclusive B decays.
In $B \to X_s \gamma $ there are perturbative $QCD$ corrections at order $\alpha_s$ not only to the single quark line process $ b \to s \gamma$ but also coming from a set of diagrams where the weak interaction vertex involves a gluon which interacts with the spectator quark in the B hadron. We discuss the impact of the full set of these diagrams. These can influence the decay rate and also the line shape of the photon spectrum as they favor a softer photon energy than does the pure spectator decay $b \to s \gamma$. A subset of these diagrams generate differences in the decay rates for charged and neutral B's , $B^+ \to X_s \gamma$ vs. $B^0 \to X_s \gamma$ which can be searched for experimentally, although our calculation indicates that the effect will be hard to observe. Bound state effects turn out to be required to give rise to spectator corrections to the decay rate at order $\alpha_s$. The resulting contribution to the total rate is rather small (of about $5 \% $ ), although the effect is somewhat larger on portions of the photon spectrum.
14759150
Heavy meson molecules in effective field theory
We consider the implications from the possibility that the recently observed state X(3872) is a meson-antimeson molecule. We write an effective Lagrangian consistent with the heavy-quark and chiral symmetries needed to describe X(3872). We explore the consequences of the assumption that X(3872) is a molecular bound state of D�0 and D0 mesons for the existence of bound states in the D0D0 and D�0D �0
12690711
Lorentz-CPT violation, radiative corrections and finite temperature
In this work we investigate the radiatively induced Chern-Simons-like terms in four-dimensions at zero and finite temperature. We use the approach of rationalizing the fermion propagator up to the leading order in the CPT-violating coupling bμ. In this approach, we have shown that although the coefficient of Chern-Simons term can be found unambiguously in different regularization schemes at zero or finite temperature, it remains undetermined. We observe a correspondence among results obtained at finite and zero temperature.
119127214
On the aether-like Lorentz-breaking action for the electromagnetic field
We study the generation of aether-like Lorentz-breaking actions in three, four and five dimensions via an appropriate Lorentz-breaking coupling of electromagnetic and spinor fields. Special attention is given to the four-dimensional case where we discuss the issue of ambiguities.
85539374
On the effective potential for Horava–Lifshitz-like theories with the arbitrary critical exponent
Abstract We calculate the one-loop effective potential for Horava–Lifshitz-like QED and Yukawa-like theory for arbitrary values of the critical exponent and the space–time dimension.
1344998
Quantum superfield supersymmetry
This paper is a collection of lecture notes on the superfield approach in three- and four-dimensional supersymmetric quantum field theory. Many examples of the applications of this approach to different superfield models are considered.
118701501
Liouville-like solutions in dilaton gravity with Gauss–Bonnet modifications
We investigate non-perturbative dilatonic solutions of the wide class of the modified gravity models that include Gauss–Bonnet terms with a general F(G) Lagrangian. We show that the presence of Liouville-like solutions is a characteristic feature of these models.