119268040
Constraining RS Models by Future Flavor and Collider Measurements: A Snowmass Whitepaper
Randall-Sundrum models are models of quark flavor, because they explain the hierarchies in the quark masses and mixings in terms of order one localization parameters of extra dimensional wavefunctions. The same small numbers which generate the light quark masses suppress contributions to flavor violating tree level amplitudes. In this note we update universal constraints from electroweak precision parameters and demonstrate how future measurements of flavor violation in ultra rare decay channels of Kaons and B mesons will constrain the parameter space of this type of models. We show how collider signatures are correlated with these flavor measurements and compute projected limits for direct searches at the 14 TeV LHC run, a 14 TeV LHC luminosity upgrade, a 33 TeV LHC energy upgrade, and a potential 100 TeV machine. We further discuss the effects of a warped model of leptons in future measurements of lepton flavor violation.
119289443
Flavor physics in the Randall-Sundrum model: II. Tree-level weak-interaction processes
A comprehensive analysis of tree-level weak interaction processes at low energy is presented for the Randall-Sundrum (RS) model with SU(2)L × U(1)Y bulk gauge symmetry and brane-localized Higgs sector. The complete form of the effective weak Hamiltonian is obtained, which results from tree-level exchange of Kaluza-Klein (KK) gluons and photons, the W± and Z0 bosons and their KK excitations, as well as the Higgs boson. Exact expressions are used for the bulk profiles of the various fields, and for the exchange of entire towers of KK gauge-boson states. A detailed phenomenological analysis is performed for potential new-physics effects in neutral-meson mixing and in rare decays of kaons and B mesons, including both inclusive and exclusive processes. We find that while the predictions for ∆F = 2 observables are rather model-independent, ∆F = 1 processes depend sensitively on the exact realizations of the electroweak gauge and the fermionic sector. In this context, we emphasize that the localization of the right-handed top quark in the extra dimension plays a crucial role in the case of rare Z0-mediated decays, as it determines the relative size of left- to right-handed couplings. We also extend earlier studies of quark flavor-changing neutral currents by examining observables which up to now attracted little attention. These include $$ D - \overline D $$ mixing, B → τντ, B → Xs(K*) l+l-, ϵ′K/ϵK, $$ \overline B \to \pi \overline K $$, $$ {\overline B^0} \to \phi {K_S} $$, $$ {\overline B^0} \to \eta '{K_S} $$, and B+ → π+π0.
38251987
Solution to the flavor problem of warped extra-dimension models.
A minimal solution to the flavor problem of warped extra-dimension models, i.e., the excessive mixed-chirality contribution to CP violation in K-K ¯ mixing arising from Kaluza-Klein (KK) gluon exchange, is proposed. Extending the strong-interaction gauge group in the bulk by an additional SU(3), and breaking this symmetry to QCD via boundary conditions, the constraints arising from the ε(K) parameter are significantly relaxed. As a result, KK scales M(KK)~2 TeV are consistent with all flavor observables without significant fine-tuning. The model predicts an extended Higgs sector featuring massive color-octet scalars and a tower of KK pseudoaxial gluon resonances, whose existence is not in conflict with recent LHC dijet bounds.
118512166
Top-quark forward-backward asymmetry in Randall-Sundrum models beyond the leading order
We calculate the $ t\overline t $ forward-backward asymmetry, AtFB, in Randall-Sundrum (RS) models taking into account the dominant next-to-leading order (NLO) corrections in QCD. At Born level we include the exchange of Kaluza-Klein (KK) gluons and photons, the Z boson and its KK excitations, as well as the Higgs boson, whereas beyond the leading order (LO) we consider the interference of tree-level KK-gluon exchange with one-loop QCD box diagrams and the corresponding bremsstrahlungs corrections. We find that the strong suppression of LO effects, that arises due to the elementary nature and the mostly vector-like couplings of light quarks, is lifted at NLO after paying the price of an additional factor of αs/(4π). In spite of this enhancement, the resulting RS corrections in AtFB remain marginal, leaving the predicted asymmetry SM-like. As our arguments are solely based on the smallness of the axial-vector couplings of light quarks to the strong sector, our findings are model-independent and apply to many scenarios of new physics that address the flavor problem via geometrical sequestering.
110822912
Monolithic systems design for the Silicon Electromagnetic Calorimetry Collaboration
A series of monolithic bipolar charge-sensitive preamplifiers and a companion monolithic 50-ns CMOS shaping amplifier have been designed, fabricated, and characterized for use with silicon calorimeters. The preamplifier topologies evaluated were current-mode, folded cascode, and differential. These three topologies were fabricated in the Harris Semiconductor VHF process and were characterized for noise, transient response, power dissipation and radiation hardness. Versions of each preamplifier have been designed to operate over a range of detector pad capacitance from 20-500 pF. The CMOS shaping amplifier specifications and test results are presented with emphasis on the system integration requirements for beam tests. >
119381704
Fusion and singular vectors inA1(1) highest weight cyclic modules
We show how the interplay between the fusion formalism of conformal field theory and the Knizhnik-Zamolodchikov equation leads to explicit formulae for the singular vectors in the highest weight representations ofA1(1).
121325077
On some relations between local height probabilities and conformal invariance
Abstract We observe that the expressions of order parameters (“local height probabilities”) in the regime III of integrable A, D lattice models are closely related to the partition functions of the associated minimal critical theories in a finite box with appropriate boundary conditions. This is more precisely stated in terms of corner transfer matrix properties. Our work thus points out a relation between integrable systems off critically and in the thermodynamic limit with models at critically but in a finite box, once the nome which parametrizes the elliptic Boltzmann weights in the former case is identified with the modular parameter in the latter. As an application we are able to obtain some new properties of the LHP for D N or E 6 , E 7 , E 8 models using conformal invariance techniques only.
15486552
Comments on the links between SU(3) modular invariants, simple factors in the Jacobian of Fermat curves, and rational triangular billiards
We examine the proposal made recently that the su(3) modular invariant partition functions could be related to the geometry of the complex Fermat curves. Although a number of coincidences and similarities emerge between them and certain algebraic curves related to triangular billiards, their meaning remains obscure. In an attempt to go beyond the su(3) case, we show that any rational conformal field theory determines canonically a Riemann surface. Comment: 56 pages, 4 eps figures, LaTeX, uses epsf
5911478
Phase transition with the Berezinskii-Kosterlitz-Thouless singularity in the Ising model on a growing network.
We consider the ferromagnetic Ising model on a highly inhomogeneous network created by a growth process. We find that the phase transition in this system is characterized by the Berezinskii-Kosterlitz-Thouless singularity, although critical fluctuations are absent and the mean-field description is exact. Below this infinite order transition, the magnetization behaves as exp((-const/square root of(Tc-T)). We show that the critical point separates the phase with the power-law distribution of the linear response to a local field and the phase where this distribution rapidly decreases. We suggest that this phase transition occurs in a wide range of cooperative models with a strong infinite-range inhomogeneity.