We investigate the spectra of light scalar and vector glueballs in a holografic description of QCD with a dilaton background bulk field. In particular, we study how the glueball masses depend on the conditions on the dilaton background and on the geometry of the bulk.Comment: LaTex, 13 pages, 2 figure

The simplest extension of the Standard Model (SM) that generally introduces new sources of flavour violation and CP violation as well as right-handed (RH) currents is the addition of a U (1) gauge symmetry to the SM gauge group. If the corresponding heavy gauge boson (Z ) mediates FCNC processes in the quark sector at tree-level, these new physics (NP) contributions imply a pattern of deviations from SM expectations for FCNC processes that depends only on the couplings of Z to fermions and on its mass. This implies stringent correlations between ∆F = 2 and ∆F = 1 observables which govern the landscape of the allowed parameter space for Z -models. Anticipating the Flavour Precision Era (FPE) ahead of us we illustrate this by searching for allowed oases in this landscape assuming significantly smaller uncertainties in CKM and hadronic parameters than presently available. To this end we analyze ∆F = 2 observables in K 0 −K 0 and B 0 s,d −B 0 s,d systems and rare K and B decays including both left-handed and right-handed Z -couplings to quarks in various combinations. We identify a number of correlations between various flavour observables that could test and distinguish these different Z scenarios. The important role of b → s + − and b → sνν transitions in these studies is emphasized. Imposing the existing flavour constraints, a rich pattern of deviations from the SM expectations in B s,d and K meson systems emerges provided M Z ≤ 3 TeV. While for M Z ≥ 5 TeV Z effects in rare B s,d decays are found typically below 10% and hard to measure even in the FPE, K → πνν and K L → π 0 + − decays provide an important portal to scales beyond those explored by the LHC. We apply our formalism to NP scenarios with induced flavour changing neutral Z-couplings to quarks. We find that in the case of B d and K decays such Z-couplings still allow for sizable departures from the SM. On the other hand in the B s system, constraints on b → s + − transitions basically eliminate NP effects from such couplings.

An analytic result for the O(α s ) corrections to the triple differential B → X u lν l decay rate is presented, to leading order in the heavy-quark expansion. This is relevant for computing partially integrated decay distributions with arbitrary cuts on kinematic variables. Several double and single differential distributions are derived, most of which generalize known results. In particular, an analytic result for the O(α s ) corrections to the hadronic invariant mass spectrum is presented. The effects of Fermi motion, which are important for the description of decay spectra close to infrared sensitive regions, are included. The behaviour of perturbation theory in the region of time-like momenta is also investigated.

All the available experimental information on open charm and beauty mesons is used to classify the observed states in heavy quark doublets. The masses of some of the still unobserved states are predicted, in particular in the beauty sector. Adopting an effective Lagrangian approach based on the heavy quark and chiral symmetry, individual decay rates and ratios of branching fractions are computed, with results useful to assign the quantum numbers to recently observed charmed states which still need to be properly classified. Implications and predictions for the corresponding beauty mesons are provided. The experimental results are already copious, and are expected to grow up thanks to the experiments at the LHC and to the future high-luminosity flavour and $p-\bar p$ facilities.Comment: RevTex, 15 pages, 1 figure. Corrected Equations (8) and (9

Abstract:We investigate how the 331 models, based on the gauge group SU(3) C × SU(3) L ×U(1) X face new data on B s,d → µ + µ − and B d → K * (K)µ + µ − taking into account present constraints from ∆F = 2 observables, low energy precision measurements, LEP-II and the LHC data. In these models new sources of flavour and CP violation originate dominantly through flavour violating interactions of ordinary quarks and leptons with a new heavy Z gauge boson. The strength of the relevant couplings is governed by four new parameters in the quark sector and the parameter β which in these models determines the charges of new heavy fermions and gauge bosons. We study the implications of these models for β = ±n/ √ 3 with n = 1, 2, 3. The case β = − √ 3 leading to Landau singularities for M Z ≈ 4 T eV can be ruled out when the present constraints on Z couplings, in particular from LEP-II, are taken into account. For n = 1, 2 interesting results are found for M Z < 4 T eV with largest NP effects for β < 0 in B d → K * µ + µ − and the ones in B s,d → µ + µ − for β > 0. As Re(C NP 9 ) can reach the values −0.8 and −0.4 for n = 2 and n = 1, respectively the B d → K * µ + µ − anomalies can be softened with the size depending on ∆M s /(∆M s ) SM and the CP-asymmetry S ψφ . A correlation between Re(C NP 9 ) and B(B s → µ + µ − ), identified for β < 0, implies for negative Re(C NP 9 ) uniquely suppression of B(B s → µ + µ − ) relative to its SM value which is favoured by the data. In turn also S ψφ < S SM ψφ is favoured with S ψφ having dominantly opposite sign to S SM ψφ and closer to its central experimental value. Another triple correlation is the one between Re(C NP 9 ), B(B s → µ + µ − ) and B(B d → Kµ + µ − ). NP effects in b → sνν transitions, K + → π + νν and K L → π 0 νν turn out to be small. We find that the absence of B d → K * µ + µ − anomalies in the future data and confirmation of the suppression of B(B s → µ + µ − ) relative to its SM value would favour β = 1/ √ 3 and M Z ≈ 3 T eV . Assuming lepton universality, we find an upper bound |C NP 9 | ≤ 1.1(1.4) from LEP-II data for all Z models with only left-handed flavour violating couplings to quarks when NP contributions to ∆M s at the level of 10%(15%) are allowed.