In this work we investigate the contribution to B(d,s) mixing from both scalar and vector unparticles in a number of scenarios. The emphasis of this work is to show the impact of the recently discovered 3 sigma evidence for new physics found in the CP phase of B(s) mixing. Here we show that the inclusion of the CP phase constraints for both B(d) and B(s) mixing improves the bounds set on the unparticle couplings by a factor of 2~4, and one particular scenario of scalar unparticles is found to be excluded by the 3 sigma measurement of phi(s).
The unparticle effects on the $\Bs$-$\Bsbar$ mixing is revisited. Taking into account the unitarity constraints on the unparticle operators, we find that the contribution of the vector unparticle is very suppressed compared to that of the scalar unparticle. This is due to the fact that the lower bound of the scaling dimension of the vector-unparticle operator is larger. It is also shown that the mixing phase from the scalar unparticle is negative, and unparticles can produce large mixing phase.
In this letter we consider the case of primary scalar unparticle contributions to B(d,s) mixing. With particular emphasis on the impact of the recent hint of new physics in the measurement of the B(s) mixing phase, phi(s), we determine the allowed parameter space and impose bounds on the unparticle couplings.
The mixing of $K^0-\bar{K^0}$, $D^0-\bar{D^0}$ and $B_{(s)}^0-\bar{B^0_{(s)}}$ provides a sensitive probe to explore new physics beyond the Standard Model. The scale invariant unparticle physics recently proposed by Georgi can induce flavor-changing neutral current and contribute to the mixing at tree level. We investigate the unparticle effects on $B^0-\bar{B^0}$ and $D^0-\bar{D^0}$ mixing. Especially, the newly observed $D^0-\bar{D^0}$ mixing sets the most stringent constraints on the coupling of the unparticle to quarks.
The neutral kaon meson mixing plays an important role in test of the Standard Model (SM) and new physics beyond it. Scale invariant unparticle physics induces a flavor changing neutral current (FCNC) transition of $K^0-\bar K^0$ oscillation at the tree level. In this study, we investigate the scale invariant unparticle physics effects on the $K^0-\bar K^0$ mixing. Based on the current experimental data, we give constraints of $K^0-\bar K^0$ mixing on the unparticle parameters.
We study the the electroweak symmetry breaking induced by the interaction of unparticles and the SM Higgs with an additional complex scalar. Furthermore, we estimate the contribution of the mixing scalars on the muon anomalous magnetic moment. We observe that this contribution is at least two order less than the discrepancy between the experimental and the SM results of the muon anomalous magnetic moment.
We study the effect of unparticle stuff on $B_s - \bar{B}_s$ mixing and consider possible implications of it for the decaymodes $B_s \to J/ψϕ$ and $ϕϕ$. We find that due to the new contributions from the unparticles the $B_s - \bar{B}_s$ mixing phase could be observable at the LHC along with the possible sizable CP asymmetry parameters $S_{ψϕ(ϕϕ)}$ in $B_s \to J/ψϕ(ϕϕ)$ decay modes.
Motivated by slow-roll inflationary cosmology we study a scalar unparticle weakly coupled to a Higgs field in the broken symmetry phase. The mixing between the unparticle and the Higgs field results in a seesaw type matrix and the mixing angles feature a Mikheyev-Smirnov-Wolfenstein (MSW) effect as a consequence of the unparticle field being noncanonical. We find two (MSW) resonances for small and large spacelike momenta. The unparticlelike mode features a nearly flat potential with spinodal instabilities and a large expectation value. An effective potential for the unparticlelike field is gen…
We consider the dark matter scalar in the Randall Sundrum background and study the annihilation cross section if the curvature-scalar mixing is switched on. In this case, in addition to the radion, the standard model Higgs scalar drives the annihilation and it leads to a considerable enhancement in the annihilation cross section. Furthermore we take unparticle, having a non-zero mass coming from the standard model Higgs-unparticle interaction in the low energy level, as a dark matter candidate and analyze the annihilation cross section by including the effect of the curvature-scalar mixing. We…
We investigate unparticle effects in B_s mixing. In particular we discuss the possibility of reproducing the experimental result of ΔM_s, while having large effects on the mixing phase ϕ_s, which might be visible in current experiments.
We investigate the implication of unparticle physics on the B_{u,d}\to (π, K) πdecays under the constraints of the B_{d,s}-\bar B_{d,s} mixing. We found that not only the unparticle parameters that belong to the flavor changing neutral current (FCNC) processes but also scaling dimension d_{\UP} could be constrained by the B_{d,s}-\bar B_{d,s} mixing phenomenology. Employing the minimum χ^2 analysis to the B_{u,d}\to (π, K) πdecays with the constraints of B_{d,s} mixing, we find that the puzzle of large branching ratio for B_{d}\to π^0 π^0 and the discrepancy between the standard model estimati…
Exchange of unparticle stuff of dimension $d_\U$ with FCNC interaction can induce $M^{12,u}$ and $Γ^{12,u}$ causing meson and anti-meson mixing with the relation $Γ^{12,u}/M^{12,u} = 2 \tan(πd_\U)$. We show that this type of unparticle contribution can provide the much needed large $Γ^{12}_s$ to explain the recently observed anomalously large dimuon asymmetry in $B_s -\bar B_s$ system reported by D0 collaboration. The same interaction can also accommodate large mixing induced CP violation in $B_s \to J/ψϕ$ indicated by CDF and D0 data. Experimental data can provide constraints on the unparticl…
We have analyzed the electron anti-neutrino scattering off electrons and the electron anti-neutrino-nuclei coherent scattering in order to obtain constraints on tensorial couplings. We have studied the formalism of non-standard interactions (NSI), as well as the case of Unparticle physics. For our analysis we have focused on the recent TEXONO collaboration results and we have obtained current constraints to possible electron anti-neutrino-electron tensorial couplings in both new physics formalisms. The possibility of measuring for the first time electron anti-neutrino-nucleus coherent scatteri…
A renormalizable coupling between the Higgs and a scalar unparticle operator O_U of non-integer dimension d_U<2 triggers, after electroweak symmetry breaking, an infrared divergent vacuum expectation value for O_U. Such IR divergence should be tamed before any phenomenological implications of the Higgs-unparticle interplay can be drawn. In this paper we present a novel mechanism to cure that IR divergence through (scale-invariant) unparticle self-interactions, which has properties qualitatively different from the mechanism considered previously. Besides finding a mass gap in the unparticle con…
We study the possible annihilation cross section of scalar dark matter and its coupling λ_D to the standard model Higgs in the case of the electroweak symmetry breaking driven by unparticle. Here the annihilation process occurs with the help of three intermediate scalars which appear after the mixing. By respecting the annihilation rate which is compatible with the current relic density we predict the tree level coupling λ_D. We observe that the unparticle scaling d_u plays a considerable role on the annihilation process and, therefore, on the coupling λ_D.
Recently, conceptually new physics beyond the Standard Model has been proposed by Georgi, where a new physics sector becomes conformal and provides "unparticle" which couples to the Standard Model sector through higher dimensional operators in low energy effective theory. Among several possibilities, we focus on operators involving the (scalar) unparticle, Higgs and the gauge bosons. Once the Higgs develops the vacuum expectation value (VEV), the conformal symmetry is broken and as a result, the mixing between the unparticle and the Higgs boson emerges. In this paper, we consider the unparticl…
We investigate the effects of scalar and vector unparticles on top quark spin correlations via the process $e^{+}e^{-}\to t \bar{t}$. In addition to the Standard Model diagrams, there is a new contribution to top-antitop quark production process mediated by unparticle in the s-channel. It is shown that scalar and vector unparticle contribution leads to a considerable deviation of the top spin correlations from the Standard Model one.
We present the phenomenology of antisymmetric rank-2 tensor unparticle operator ${\cal O}_{\cal U,A}^{μν}$ with scaling dimension $d_{\cal U}$. We consider the physical effects of operator $O_{\cal U,A}^{μν}$ in $Z^0$ boson invisible decays $Z^0 \to {\cal U}$, $Z^0 \to b \bar{b}$ channel, the electroweak precision observable $S$ parameter, and the muon anomalous magnetic dipole moment. The $Z^0$ boson invisible decay gives a very stringent constraint in the $(Λ_{\cal U}, M_{\cal U})$ plane, and only small $r \equiv Λ_{\cal U} / M_{\cal U} \lesssim 0.1$ is favored, when $Λ_{\cal U}$ is order of…
We consider a sterile neutrino to be an unparticle, namely an \emph{unsterile neutrino}, with anomalous dimension $η$ and study its mixing with a canonical active neutrino via a see-saw mass matrix. We show that there is \emph{no unitary} transformation that diagonalizes the mixed propagator and a field redefinition is required. The propagating or ``mass'' states correspond to an unsterile-like and active-like mode. The unsterile mode features a complex pole or resonance for $0 \leq η< 1/3$ with an ``invisible width'' which is the result of the decay of the unsterile mode into the active mode …
Recently, conceptually new physics beyond the Standard Model has been proposed by Georgi, where a new physics sector becomes conformal and provides "unparticle" which couples to the Standard Model sector through higher dimensional operators in low energy effective theory. Among several possibilities, we focus on operators involving the (scalar) unparticle, Higgs and the gauge bosons. Once the Higgs develops the vacuum expectation value (VEV), the conformal symmetry is broken and as a result, the mixing between the unparticle and the Higgs boson emerges. In this paper, we consider a natural rea…
Fermionic unparticles are introduced and their basic properties are discussed. Some phenomenologies related are exploited, such as their effects on charged Higgs boson decays and anomalous magnetic moments of leptons. Also, it has been found that measurements of $B^0-\bar B^0$ mixing could yield interesting constraints on couplings between unparticle operators and standard model fields.
We study and analyze the recent observations of the top pair production $σ(p\bar p\to t \bar t)$ at TeVatron through flavor conserving and flavor violating channels ${\it via}$ vector and tensor unparticles. The unparticle sector is considered with the possibility of being a color singlet or octet. The modified unparticle propagator is used to investigate the contribution of these unparticles to the observed $A_{FB}^{t\bar t}$ (forward backward asymmetry in top pair production) and the spin correlation at TeVatron. We have also studied the impact of the flavor violating couplings of unparticle…
According to the standard model, the Cabibbo-favored (CF) decays are $CP$ conserve at tree level. Observation of any finite $CP$ asymmetry can be received as a signal of new physics. In CF charm meson decays, $ D^0 \rightarrow K^- π^+ $ and $ D^+ \rightarrow K_s^0 π^+ $, the following experimental values for their $CP$ asymmetry are reported, respectively: ($0.3 \pm 0.7$) % and ($-0.41 \pm 0.09$) %. The value of the later can be attributed to the mixing of $ K^0 $ and $ \overline{K^0} $, however, its contribution is about ($-0.332 \pm 0.006 $) %. In this paper, we use these experimental result…
Recently, conceptually new physics beyond the Standard Model has been proposed, where a hidden conformal sector provides ``unparticle'' which couples to the Standard Model sector through higher dimensional operators in low energy effective theory. Among several possibilities, we focus on operators involving unparticle, the Higgs doublet and the gauge bosons. Once the Higgs doublet develops the vacuum expectation value, the conformal symmetry is broken and as a result, the mixing between unparticle and Higgs boson emerges. We find that this mixing can cause sizable shifts for the couplings betw…
We consider a sterile neutrino to be an unparticle, namely an "unsterile" neutrino, and study its mixing with a canonical active neutrino via a see-saw mass matrix. There is no unitary transformation that diagonalizes the mixed propagator and a field redefinition is required. The unsterile-like propagating mode features a resonance for anomalous dimension between 0 and 1/3, but the complex pole disappears when the anomalous dimension is larger than 1/3. The active-like propagating mode is described by a stable pole, but inherits a non-vanishing spectral density above the unparticle threshold. …
Among different measured observables of top-antitop quark pairs at hadron colliders, the forward-backward asymmetry ($A_{\text{FB}}$) measured by the CDF and D0 collaborations has inconsistency with the Standard Model prediction. The measured forward-backward asymmetry grows with $t\bar{t}$ invariant mass. Several new physics models have been proposed to explain this deviation. We consider the consistency of the parameter space of vector unparticle (in Flavor-Conserving scenario) with the existing $t\bar{t}$ production measurements. In particular, we look at the total cross sections at the LHC…
Low energy phenomenology of the unparticle physics associated with an exact scale invariant sector possessing a non-trivial infrared fixed point at a higher energy scale is explored for both electron-positron and hadronic colliders. Feynman rules for a spin 0, 1 or 2 unparticle coupled to a variety of standard model gauge invariant operators that are relevant to many low energy processes involving either real emissions of unparticles or their virtual propagator effects are presented. Missing energy and/or recoil mass distributions of the unparticle in the associated production of unparticle to…
Recently the DØ Collaboration reported an observation of like-sign charge asymmetry (CA), which is about $3.2 σ$ deviation from the standard model (SM) prediction. Inspired by the observation we investigate the scalar unparticle effects, under the color charge of $SU(3)_c$ symmetry, in the CP violation in neutral B meson oscillations as well as the dispersive and absorptive parts of $\bar B_q\leftrightarrow B_q$ transition, which can be related to the CA directly. In order to illustrate the peculiar properties of unparticle, our analysis is carried out in two scenarios for the right-handed sec…
We study the constraint arising from the recently observed D - anti-D mixing in the context of supersymmetric models with left-right symmetry. In these models, the supersymmetric contributions in the mixing amplitudes of D - anti-D, K - anti-K and B - anti-B are all correlated. We compare the constraint from the D - anti-D mixing with the K - anti-K mixing and find that the D - anti-D mixing constrains the maximal supersymmetric contribution to the B_s - anti-B_s mixing amplitude. The maximal supersymmetric contribution can allow a large CP phase of B_s - anti-B_s mixing which agrees with the …
The nonleading corrections in the inverse mass of the heavy charmed quark to the effective local ΔS=2 Lagrangian of K^0-anti K^0 mixing are calculated within the standard model.
We point out how, in certain models, the same combination of New Physics couplings occur in the amplitudes for both D0-anti-D0 mixing and the rare decays D0 -> l+l-. If the New Physics dominates and is responsible for the observed mixing, then a very simple correlation exists between the magnitudes of each; in fact the rates for the decay D0 -> l+l- are completely fixed by the mixing. Observation of D0 -> l+l- in excess of the Standard Model prediction could identify New Physics contributions to D0-anti-D0 mixing.
We present a calculation of the B0 - anti-B0 mixing matrix element in the framework of QCD sum rules for three-point functions. We compute alpha_s corrections to a three-point function at the three-loop level in QCD perturbation theory, which allows one to extract the matrix element with next-to-leading order (NLO) accuracy. This calculation is imperative for a consistent evaluation of experimentally-measured mixing parameters since the coefficient functions of the effective Hamiltonian for B0 - anti-B0 mixing are known at NLO. We find that radiative corrections violate factorization at NLO; t…
We reanalyze the recent data from the Liquid Scintillator Neutrino Detector (LSND) experiment, that might indicate anti-nu_mu<--->anti-nu_e mixing. This indication is not completely excluded by the negative results of established accelerator and reactor neutrino oscillation searches. We quantify the region of compatibility by means of a thorough statistical analysis of all the available data, assuming both two-flavor and three-flavor neutrino oscillations. The implications for various theoretical scenarios and for future oscillation searches are studied. The relaxation of the LSND constraints …
The Bs-Bsbar mixing parameter Delta Ms is studied in the MSSM with large tan beta. The recent Tevatron measurement of Delta Ms is used to constrain the MSSM parameter space. From this analysis the often neglected contribution to Delta Ms from the operator Q^SLL is found to be significant.
In current searches for D0 anti-D0 mixing, the time evolution of ``wrong-sign'' decays is used to distinguish between a potential mixing signal and the dominant background from doubly-Cabibbo-suppressed decays. A term proportional to $ΔMt$ in the expression for the time evolution is often neglected in theoretical discussions and experimental analyses of these processes. We emphasize that, in general, this term does not vanish even in the case of CP invariance. Furthermore, CP invariance is likely to be violated if the rate of D0 anti-D0 mixing is close to the experimental bound. The consequenc…
We show that because of the milder GIM suppression, the four-quark dipenguin operator contributes to the short distance piece of the D^0-\bar D^0 mixing amplitude at the same order of magnitude as the box diagram. In addition, we put an upper bound Δm_D^{LDR} \leq 5 \times Δm_D^{box} on a long-distance resonant contribution induced by the penguin mixing.
In supersymmetric models with nonzero Majorana neutrino mass, the sneutrino and antisneutrino mix, which may lead to same sign dilepton signals in future collider experiments. We point out that the anomaly-mediated supersymmetry breaking scenario has a good potential to provide an observable rate of such signals for the neutrino masses suggested by the atmospheric and solar neutrino oscillations. The sneutrino mixing rate is naturally enhanced by m_{3/2}/m_{\tildeν}={\cal O}(4π/α) while the sneutrino decay rate is small enough on a sizable portion of the parameter space. We point out also that…
I review constraints on possible New Physics interactions from D0-anti-D0 mixing measurements. I consider the most general low energy effective Hamiltonian and include leading order QCD running of effective operators. I discuss constraints from an extensive list of popular New Physics models, each of which could be discovered at the LHC, that can generate these operators. In most of the scenarios, strong constraints that surpass those from other search techniques could be placed on the allowed parameter space using the existent evidence for observation of D-meson mixing.
The Standard Model contribution to D0-anti-D0 mixing is dominated by the contributions of light s and d quarks. Neglecting the tiny effects due to b quark, both mass and lifetime differences vanish in the limit of SU(3) symmetry. Thus, the main challenge in the Standard Model calculation of the mass and width difference in the D0-anti-D0 system is to estimate the size of SU(3) breaking effects. We prove that D meson mixing occurs in the Standard Model only at second order in SU(3) violation. We consider the possibility that phase space effects may be the dominant source of SU(3) breaking. We f…
We present the result for the invariant B_K factor of K0-anti-K0 mixing in the chiral limit and to next-to-leading order in the 1/Nc expansion. We explicitly demonstrate the cancellation of the renormalization scale and scheme dependences between short- and long-distance contributions in the final expression. Numerical estimates are then given, by taking into account increasingly refined short- and long-distance constraints of the underlying QCD Green's function which governs the B_K factor.
In this letter, we propose three different strategies to extract the weak mixing angle phi_s of the Bs system using penguin-mediated decays into vectors, mainly Bs->K*K*, Bs->phi K* and Bs->phi phi. We also provide predictions for the longitudinal branching ratio and CP-asymmetries of Bs->K*K* using a method that combines QCD factorisation with flavour symmetries to relate this decay to its Bd counterpart.
We describe a fit to the charged fermion mass hierarchy using the chiral quantum numbers of the maximal anti-grand unification group $SMG^3 \times U(1)_f$, where $SMG \equiv SU(3) \times SU(2) \times U(1)$. This fit suggests a set of Higgs fields responsible for the breakdown, near the Planck scale, of $SMG^3 \times U(1)_f$ to the Standard Model group.
The first general analysis of New Physics contributions to the D0-anti-D0 lifetime difference (equivalently Delta Gamma_D} is presented. The extent to which New Physics (NP) contributions to |Delta C|=1 processes can produce effects in Delta Gamma_D, even if such NP contributions are undetectable in the current round of D0 decay experiments, is studied. New Physics models which do and do not dominate the lifetime difference in the flavor SU(3) limit are identified. Specific examples are provided.
We study the B-parameter (``bag factor'') for B-anti-B mixing within a recently developed heavy-light chiral quark model. Non-factorizable contributions in terms of gluon condensates and chiral corrections are calculated. In addition, we also consider 1/m_Q corrections within heavy quark effective field theory. Perturbative QCD effects below μ= m_b known from other work are also included. Considering two sets of input parameters, we find that the renormalization invariant B-parameter is B = 1.51 +- 0.09 for B_d and B = 1.40 +- 0.16 for B_s.
The fermion masses and mixing angles are fitted using only 3 free parameters in a non-supersymmetric extension of the Standard Model, with new approximately conserved chiral gauge quantum numbers broken by a set of Higgs fields. The fundamental mass scale of this anti-grand unification model is given by the Planck mass. We also calculate neutrino mixing angles and masses, as well as CP violation from the CKM matrix. A good fit is obtained to the observed fermion masses but our predictions of the neutrino masses are too small to lead to any observable neutrino oscillation effects claimed today,…
We combine the analyses for flavor changing neutral current processes and dark matter solutions in minimal-type supersymmetric grand unified theory (GUT) models, SO(10) and SU(5), with a large B_s - anti-B_s mixing phase and large tan beta. For large tan beta, the double penguin diagram dominates the SUSY contribution to the B_s - anti-B_s mixing amplitude. Also, the Br(B_s -> mu mu) constraint becomes important as it grows as tan^6 beta, although it can still be suppressed by large pseudoscalar Higgs mass m_A. We investigate the correlation between B_s -> mu mu and the dark matter direct dete…
In this work we re-examine the correlation between B(d,s)-anti-B(d,s) mixing and Lepton Flavour Violation in the light of recent experimental measurements in the $B_s$ system. We perform a generic SUSY analysis of the allowed down squark mass insertion parameter space. In the SUSY GUT scenario this parameter space is then used to make predictions for LFV branching ratios. We find that the recent measurement for the CP phase $ϕ_s$ excludes the lowest rates for tau --> mu + gamma and provides a lower bound of ~ 3E-9 for tan beta = 10. Future experimental improvements in the bound on tau --> mu +…
The motivation most often cited in searches for D0-anti-D0 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 D0-anti-D0 mixing parameters, concentrating on possible effects of New Physics.
The motivation most often cited in searches for D0-anti-D0 mixing lies with the possibility of observing a signal from new physics which dominates that from the Standard Model. We discuss recent theoretical and experimental results in D0-anti-D0 mixing, including new experimental measurements from CLEO and FOCUS collaborations and their interpretations.
The non-minimal flavour violating interactions of mirror quarks and new heavy gauge bosons in the Littlest Higgs model with T-parity (LHT) give rise to naturally large CP-violating effects in the B_s system. In view of a large new CP phase in B_s - anti-B_s mixing hinted by the CDF and D0 data and the recent UTfit analysis, we update our 2006 analysis of particle-antiparticle mixing and rare K and B decays in the LHT model, using the most recent values of a number of input parameters and performing a more careful error analysis. We find that the CP-asymmetry S_{psi phi} can easily reach values…
A new S3 flavor model based on $\mathrm{SU}(3)_C \otimes \mathrm{SU}(3)_L \otimes \mathrm{U}(1)_X$ gauge symmetry responsible for fermion masses and mixings different from our previous work is constructed. The new feature is a two - dimensional representation of a Higgs anti-sextet under $S_3$ which responsible for neutrino masses and mixings. The neutrinos acquire small masses from only an anti-sextet of $\mathrm{SU(3)}$ which is in a doublet under $S_3$. If the difference of components of the anti-sextet is regarded as a small perturbation, S3 is equivalently broken into identity, the corres…
The neutrino parameters determined from the solar neutrino data and the anti-neutrino parameters determined from KamLAND reactor experiment are in good agreement with each other. However, the best fit points of the two sets differ from each other by about $10^{-5}$ eV$^2$ in mass-square differenc and by about $2^\circ$ in the mixing angle. Future solar neutrino and reactor anti-neutrino experiments are likely to reduce the uncertainties in these measurements. This, in turn, can lead to a signal for CPT violation in terms a non-zero difference between neutrino and anti-neutrino parameters. In t…
The motivation most often cited in searches for D0-anti-D0 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 D0-anti-D0 mixing parameters. We also discuss the current status of searches for CP-violation in charmed meson transitions, as well as some recent theoretical ideas.
Neutral mesons exhibit a phenomenon called flavour mixing. As a consequence of a second order weak process the flavour eigenstates corresponding to the meson and its anti-meson are superpositions of two mass eigenstates. A meson produced in a flavour state changes into an anti-meson and back again as a function of time. Such flavour oscillations are considered sensitive probes of physics beyond the Standard Model. In this brief review I summarize the status of experimental constraints on mixing parameters in the B_s meson system.
In contrast with $B^0-\bar B^0$, $B_s-\bar B_s$ mixing where the standard model (SM) contributions overwhelm that of new physics beyond standard model (BSM), a measured relatively large $D^0-\bar D^0$ mixing where the SM contribution is negligible, definitely implies the existence of new physics BSM. It is natural to consider that the rare decays of D meson might be more sensitive to new physics, and the rare decay $D^0\to μ^+μ^-$ could be an ideal area to search for new physics because it is a flavor changing process. In this work we look for a trace of new physics BSM in the leptonic decays …
We discuss the interplay of neutrino oscillation and decay properties at neutrino telescopes. Motivated by recent unparticle scenarios, which open the possibility of new neutrino decay modes over astrophysical distances, we perform a complete classification of possible decay schemes, and we illustrate how different scenarios can be identified. Moreover, we show that the sensitivity of neutrino telescopes to standard neutrino properties, such as the mass hierarchy or delta_CP, is greatly enhanced in specific decay scenarios. In particular we discuss the impact of an astrophysical neutrino detec…
We argue that extended technicolor augmented with topcolor requires that all mixing between the third and the first two quark generations resides in the mixing matrix of left-handed down quarks. Then, the anti-B_d--B_d mixing that occurs in topcolor models constrains the coloron and Z' boson masses to be greater than about 5 TeV. This implies fine tuning of the topcolor couplings to better than 1%.
We argue that there could be large, SU(3) violating resonance contributions to D -> K pi decays which would affect the extraction of the D0-anti-D0 mixing parameters from experiment. Such contributions can induce a large strong phase in the interference between the doubly Cabibbo suppressed and the mixing induced Cabibbo favored contributions to the D0 -> K^+ pi^- and anti-D0 -> K^- pi^+ decays. Consequently, the interpretation of a large, CP conserving interference term can involve a large mass difference Delta M rather than a large width difference Delta Gamma.
Three different strategies to extract the weak mixing phase phi_s of the Bs system using B--> VV decays (Bs--> K* anti-K*, Bs--> phi anti-K* and Bs--> phi phi) are discussed. Those penguin-mediated decays are computed in the framework of a new combined QCD-Factorisation/Flavour Symmetry Method. Also some comments on the recent interesting results found by Babar concerning the decay B--> K* l+l- are included.
The noteworthy BaBar and Belle evidence for $D^0$-$\bar{D}^0$ mixing motivates us to study its impact on $D^0\to K^{*\pm} K^\mp$ decays and their CP-conjugate processes. We show that both the $D^0$-$\bar{D}^0$ mixing parameters ($x$ and $y$) and the strong phase difference between $\bar{D}^0\to K^{*\pm}K^\mp$ and $D^0\to K^{*\pm}K^\mp$ transitions ($δ$) can be determined or constrained from the time-dependent measurements of these decay modes. On the $ψ(3770)$ and $ψ(4140)$ resonances at a $τ$-charm factory, it is even possible to determine or constrain $x$, $y$ and $δ$ from the time-independe…
