117791238
What can we learn from a measurement of sin(2 beta + gamma)?
The constraints on the value of the Cabibbo-Kobayashi-Maskawa phase $\ensuremath{\gamma}$ that may be achieved by prospective measurements of $\mathrm{sin}2\ensuremath{\beta}$ and $\mathrm{sin}(2\ensuremath{\beta}+\ensuremath{\gamma})$ are discussed. Significant constraints require quite small errors, and may depend on assumptions about strong phases. The measurement of $\mathrm{sin}(2\ensuremath{\beta}+\ensuremath{\gamma})$ combined with other experiments could provide valuable limits on new physics in ${B}_{d}\ensuremath{-}$ mixing.
14931156
ProbingCPviolation with time integrated decay rates into non-CPeigenstates
Many of the experiments proposed to look for interference CP violation in neutral B mesons concentrate on tagged decay into CP eigenstates. Aleksan, Dunietz, Kayser and Le Diberder have shown that one can also look for interference CP violation using tagged decays into non-CP eigenstates. In all these methods, one must trace the time dependence of the decays. In this article we discuss a new method to search for interference CP violation by using only time integrated rates into non-CP eigenstates. The method hinges on the comparison between the decays of $\Upsilon(4S)$ into $f f$, $\bar{f} \bar{f}$, and $f \bar{f}$, and also uses the rates for $l^+ f$ and $l^- f$. This method does not depend on how the $\Upsilon(4S)$ is produced; provided enough statistics, one can use both symmetric and asymmetric colliders.
119183302
CP properties of symmetry-constrained two-Higgs-doublet models
The two-Higgs-doublet model can be constrained by imposing Higgs-family symmetries and/or generalized CP symmetries. It is known that there are only six independent classes of such symmetry-constrained models. We study the CP properties of all cases in the bilinear formalism. An exact symmetry implies CP conservation. We show that soft breaking of the symmetry can lead to spontaneous CP violation (CPV) in three of the classes.
10678678
Decoupling or nondecoupling: Is that the R($b$) question?
The top quark is well known for the nondecoupling effects it implies in ρ and Rb. The recent experimental Rb data exhibits a disagreement with the SM prediction at more than the 3σ level. It is tempting to explore whether this might be due to nondecoupling New Physics effects, opposite to those of the top. We investigate this issue in the context of models with an extra family of right or left handed, singlet or doublet quarks. It is shown that, contrary to what
118851665
Implications of the Possibility that sin(2 beta) is Small
Recently, the Babar and Belle collaborations have reported their first measurements of the CP-violating asymmetry in B{sub d} {yields} {psi}K{sub S}, and more precise results will follow soon. We discuss what a future evidence for small sin2{beta} could mean, contrasting the usual possibility of new physics in the B{sub d} system, with the interesting alternative that the new physics effects are confined to the kaon system.
119445110
The Use of early data on $B \to \rho \pi$ decays
This paper reviews the Dalitz plot analysis for the decays $B^0(\bar B^0) \to \rho \pi \to \pi^+ \pi^- \pi^0$. We discuss what can be learned about the ten parameters in this analysis from untagged and from tagged time-integrated data. We find that, with the important exception of the interesting CP violating quantity $\alpha$, the parameters can be determined from this data sample -- and, hence, they can be measured at CLEO as well as at the asymmetric $B$ factories. This suggests that the extraction of $\alpha$ from the time-dependent data sample can be accomplished with a smaller data sample (and, therefore, sooner) than would be required if all ten parameters were to be obtained from that time-dependent data sample alone. We also explore bounds on the shift of the true angle $\alpha$ from the angle measured from charged $\rho$ final states alone. These may be obtained prior to measurements of the parameters describing the neutral $\rho$ channel, which are expected to be small.
118845608
Smooth thick braneworlds and the Gibbons-Kallosh-Linde no-go theorem
After working out the so called braneworld sum rules formalism in order to encompass Gauss-Bonnet terms, the generation of thick branes is proposed, even with a periodic extra dimension, what circumvents the Gibbons-Kallosh-Linde no-go theorem in this context.
118401678
Searching for Elko dark matter spinors at the CERN LHC
The aim of this paper is to explore the possibility of discovering a fermionic field with mass dimension one, the Elko field, in the Large Hadron Collider. Due to its mass dimension, an Elko can only interact either with Standard Model spinors and gauge fields at one-loop order or at tree level through a quartic interaction with the Higgs field. In this Higgs portal scenario, the Elko is a viable candidate to a dark matter constituent which has been shown to be compatible with relic abundance measurements from WMAP and direct dark matter searches. We propose a search strategy for this dark matter candidate in the channel at the LHC. We show the LHC potential to discover the Elko considering a triple Higgs–Elkos coupling as small as ~0.5 after 1 ab-1 of integrated luminosity. Some phenomenological consequences of this new particle and its collider signatures are also discussed.
31431486
Flag-dipole spinor fields in ESK gravities
We consider the Riemann-Cartan geometry as a basis for the Einstein-Sciama-Kibble theory coupled to spinor fields: we focus on f(R) and conformal gravities, regarding the flag-dipole spinor fields, type-(4) spinor fields under the Lounesto classification. We study such theories in specific cases given, for instance, by cosmological scenarios: we find that in such background the Dirac equation admits solutions that are not Dirac spinor fields, but in fact the aforementioned flag-dipoles ones. These solutions are important from a theoretical perspective, as they evince that spinor fields are not necessarily determined by their dynamics, but also a discussion on their structural (algebraic) properties must be carried off. Furthermore, the phenomenological point of view is shown to be also relevant, since for isotropic Universes they circumvent the question whether spinor fields do undergo the Cosmological Principle.
119254804
Five Dimensional f(R) Braneworld Models
After incorporating the f(R) gravity into the general braneworld sum rules scope, it is shown that some particular class of warped five dimensional nonlinear braneworld models, which may be interesting for the hierarchy problem solution, still require a negative tension brane. For other classes of warp factors (suitable and not suitable for approaching the hierarchy problem) it is not necessary any negative brane tension in the compactification scheme. In this vein, it is argued that in the bulk f(R) gravity context, some types of warp factors may be useful for approaching the hierarchy problem and for evading the necessity of a negative brane tension in the compactification scheme.
124792248
Vortices solutions in Chern-Simons-Maxwell-Higgs system
In this work we analyze some characteristics of Bogomol’nyi ’s equations for abelian gauge theories with Chern-Simons-Maxwell-Higgs terms. We don’t obt ain the complete solution for the model, but we analyze the equations in a kind of weak field appr oximation instead of using a computational analysis. Our main idea is to get some intuition on the subject. Working with the equations in such approach we reproduce the accurate behavior next to the origin.