381,658 research outputs found

    Possible signatures for tetraquarks from the decays of a0(980)a_0(980), a0(1450)a_0(1450)

    Full text link
    Based on the recent proposal for the tetraquarks with the mixing scheme, we investigate fall-apart decays of a0(980),a0(1450)a_0(980), a_0(1450) into two lowest-lying mesons. This mixing scheme suggests that a0(980)a_0(980) and a0(1450)a_0(1450) are the tetraquarks with the mixtures of two spin configurations of diquark and antidiquark. Due to the relative sign differences in the mixtures, the couplings of fall-apart decays into two mesons are strongly enhanced for a0(980)a_0(980) but suppressed for a0(1450)a_0(1450). We report that this expectation is supported by their experimental decays. In particular, the ratios of the associated partial decay widths, which depend on some kinematical factors and the couplings, are found to be around Γ[a0(980)πη]/Γ[a0(1450)πη]=2.512.54\Gamma [a_0(980)\rightarrow \pi \eta]/\Gamma [a_0(1450)\rightarrow \pi \eta] = 2.51-2.54, Γ[a0(980)KKˉ]/Γ[a0(1450)KKˉ]=0.520.89\Gamma [a_0(980)\rightarrow K\bar{K}]/\Gamma [a_0(1450)\rightarrow K\bar{K}] = 0.52-0.89, which seems to agree with the experimental ratios reasonably well. This agreement can be interpreted as the tetraquark signatures for a0(980),a0(1450)a_0(980), a_0(1450).Comment: 6 pages, no figures, more references are added, the version to be published in EPJ

    Z_{12-I} Orbifold Compactification toward SUSY Standard Model

    Full text link
    We explain the orbifold compactification in string models and present a Z_{12-I} orbifold compactification toward supersymmetric standard models. We also point out an effective R-parity from this string construction. The VEVs of gauge singlets are chosen such that phenomenological constraints are satisfied.Comment: 13 pages with 5 figure. Talk presented at "CTP Symposium on SUSY at LHC", Cairo, 11-14 March 200

    ENERGY SUBSTITUTION IN THE GULF OF MEXICO SHRIMP FISHERY

    Get PDF
    Resource /Energy Economics and Policy,

    Strong Coupling of a Cavity QED Architecture for a Current-biased Flux Qubit

    Full text link
    We propose a scheme for a cavity quantum electrodynamics (QED) architecture for a current-biased superconducting flux qubit with three Josephson junctions. The qubit operation is performed by using a bias current coming from the current mode of the circuit resonator. If the phase differences of junctions are to be coupled with the bias current, the Josephson junctions should be arranged in an asymmetric way in the qubit loop. Our QED scheme provides a strong coupling between the flux qubit and the transmission line resonator of the circuit.Comment: 5 pages, 3 figure

    Effective Action for the Scalar Field Theory with Higher Vertices

    Get PDF
    We derive a new kind of recursion relation to obtain the one-particle-irreducible (1PI) Feynman diagrams for the effective action. By using this method, we have obtained the graphical representation of the four-loop effective action in case of the general bosonic field theory which have vertices higher than the four-point vertex

    One-dimensional itinerant ferromagnets with Heisenberg symmetry and the ferromagnetic quantum critical point

    Get PDF
    We study one-dimensional itinerant ferromagnets with Heisenberg symmetry near a ferromagnetic quantum critical point. It is shown that the Berry phase term arises in the effective action of itinerant ferromagnets when the full SU(2) symmetry is present. We explicitly demonstrate that dynamical critical exponent of the theory with the Berry term is z=2+O(ϵ2)z=2 +{\rm O}(\epsilon^2) in the sense of ϵ\epsilon expansion, as previously discovered in the Ising limit. It appears, however, that the universality class at the interacting fixed point is not the same. We point out that even though the critical theory in the Ising limit can be obtained by the standard Hertz-Millis approach, the Heisenberg limit is expected to be different. We also calculate the exact electron Green functions G(x,t=0)G(x,t=0) and G(x=0,t)G(x=0,t) near the transition in a range of temperature, which can be used for experimental signatures of the associated critical points.Comment: Replaced with final version accepted in PRB; minor changes from the previous versio

    Boltzmann Equation with a Large Potential in a Periodic Box

    Full text link
    The stability of the Maxwellian of the Boltzmann equation with a large amplitude external potential Φ\Phi has been an important open problem. In this paper, we resolve this problem with a large C3C3-potential in a periodic box Td\mathbb{T}^d, d3d \geq 3. We use [1] in LpLL^p-L^{\infty} framework to establish the well-posedness and the LL^{\infty}-stability of the Maxwellian μE(x,v)=exp{v22Φ(x)}\mu_E(x,v)=\exp\{-\frac{|v|^2}{2}-\Phi(x)\}

    Semidirect Product Groups, Vacuum Alignment and Tribimaximal Neutrino Mixing

    Full text link
    The neutrino oscillation data are in very good agreement with the tribimaximal mixing pattern: \sin^2\theta_{23}=1/2, \sin^2\theta_{12}=1/3, and \sin^2\theta_{13}=0. Attempts to generate this pattern based on finite family symmetry groups typically assume that the family symmetry is broken to different subgroups in the charged lepton and the neutrino mass matrices. This leads to a technical problem, where the cross-couplings between the Higgs fields responsible for the two symmetry breaking chains force their vacuum expectation values to align, upsetting the desired breaking pattern. Here, we present a class of models based on the semidirect product group (S_3)^4 \rtimes A_4, where the lepton families belong to representations which are not faithful. In effect, the Higgs sector knows about the full symmetry while the lepton sector knows only about the A_4 factor group. This can solve the alignment problem without altering the desired properties of the family symmetry. Inclusion of quarks into the framework is straightforward, and leads to small and arbitrary CKM mixing angles. Supersymmetry is not essential for our proposal, but the model presented is easily supersymmetrized, in which case the same family symmetry solves the SUSY flavor problem.Comment: Typos fixed, 26 pages in LaTe
    corecore