7,039 research outputs found

    Flavor SU(3) analysis of charmless B->PP decays

    Full text link
    We perform a global fits to charmless BPPB \to PP decays which independently constrain the (ρˉ,ηˉ)(\bar\rho,\bar\eta) vertex of the unitarity triangle. The fitted amplitudes and phase are used to predict the branching ratios and CP asymmetries of all decay modes, including those of the BsB_s system. Different schemes of SU(3) breaking in decay amplitude sizes are analyzed. The possibility of having a new physics contribution to KπK \pi decays is also discussed.Comment: 3 pages, 2 figs. Talk given at EPS-HEP07 To appear in the proceedings, Reference adde

    |V_ub| and |V_cb|, Charm Counting and Lifetime Differences in Inclusive Bottom Hadron Decays

    Full text link
    Inclusive bottom hadron decays are analyzed based on the heavy quark effective field theory (HQEFT). Special attentions in this paper are paid to the b\to u transitions and nonspectator effects. As a consequence, the CKM quark mixing matrix elements |V_ub| and |V_cb| are reliably extracted from the inclusive semileptonic decays B\to X_u e \nu and B\to X_c e \nu. Various observables, such as the semileptonic branch ratio B_SL, the lifetime differences among B^-, B^0, B_s and \Lambda_b hadrons, the charm counting n_c, are predicted and found to be consistent with the present experimental data.Comment: 20 pages, Revtex, 4 figures and 2 table

    A mechanism for unipolar resistance switching in oxide non-volatile memory devices

    Full text link
    Building on a recently introduced model for non-volatile resistive switching, we propose a mechanism for unipolar resistance switching in metal-insulator-metal sandwich structures. The commutation from the high to low resistance state and back can be achieved with successive voltage sweeps of the same polarity. Electronic correlation effects at the metal-insulator interface are found to play a key role to produce a resistive commutation effect in qualitative agreement with recent experimental reports on binary transition metal oxide based sandwich structures.Comment: 4 pages, 2 figure

    Spin-triplet pairing instability of the spinon Fermi surface in a U(1) spin liquid

    Full text link
    Recent experiments on the organic compound \kappa-(ET)_2Cu_2(CN)_3 have provided a promising example of a two dimensional spin liquid state. This phase is described by a two-dimensional spinon Fermi sea coupled to a U(1) gauge field. We study Kohn-Luttinger-like pairing instabilities of the spinon Fermi surface due to singular interaction processes with twice-the-Fermi-momentum transfer. We find that under certain circumstances the pairing instability occurs in odd-orbital-angular-momentum/spin-triplet channels. Implications to experiments are discussed.Comment: 4 pages, 1 figur

    Inclusive Decays of Bottom Hadrons in New Formulation of Heavy Quark Effective Field Theory

    Full text link
    We apply the new formulation of heavy quark effective field theory (HQEFT) to the inclusive decays of bottom hadrons. The long-term ambiguity of using heavy quark mass or heavy hadron mass for inclusive decays is clarified within the framework of the new formulation of HQEFT. The 1/mb1/m_b order corrections are absent and contributions from 1/mb21/m_b^2 terms are calculated in detail. This enables us to reliably extract the important CKM matrix element Vcb|V_{cb}| from the inclusive semileptonic decay rates. The resulting lifetime ratios τ(Bs0)/τ(B0)\tau(B^0_s)/\tau(B^0) and τ(Λb)/τ(B0)\tau(\Lambda_b)/\tau(B^0) are found to well agree with the experimental data. We also calculate in detail the inclusive semileptonic branching ratios and the ratios of the τ\tau and β\beta decay rates as well as the charm countings in the B0B^0, Bs0B^0_s and Λb\Lambda_b systems. For B0B^0 decays, all the observables are found to be consistent with the experimental data. More precise data for the B0B^0 decays and further experimental measurements for the Bs0B^0_s and Λb\Lambda_b systems will be very useful for testing the framework of new formulation of HQEFT at the level of higher order corrections.Comment: 20 pages, RevTex, 8 figures, 3 tables, revised version with `dressed heavy quark' being addressed, to be published in Int. J. Mod. Phys.

    MACS: Multi-agent COTR system for Defense Contracting

    Get PDF
    The field of intelligent multi-agent systems has expanded rapidly in the recent past. Multi-agent architectures and systems are being investigated and continue to develop. To date, little has been accomplished in applying multi-agent systems to the defense acquisition domain. This paper describes the design, development, and related considerations of a multi-agent system in the area of procurement and contracting for the defense acquisition community

    Puzzles in BB physics

    Get PDF
    I discuss some puzzles observed in exclusive BB meson decays, concentrating on the large difference between the direct CP asymmetries in the B0πK±B^0\to \pi^\mp K^\pm and B±π0K±B^\pm\to \pi^0 K^\pm modes, the large B0π0π0B^0\to\pi^0\pi^0 branching ratio, and the large deviation of the mixing-induced CP asymmetries in the bsqqˉb\to sq\bar q penguins from those in the bccˉsb\to c\bar c s trees.Comment: 6 pages, 1 figure, talk presented at the 9th Workshop on High Energy Physics Phenomenology, Bhubaneswar, Orissa, India, Jan. 3-14, 2006; reference adde

    Fully supersymmetric CP violations in the kaon system

    Get PDF
    We show that, on the contrary to the usual claims, fully supersymmetric CP violations in the kaon system are possible through the gluino mediated flavor changing interactions. Both ϵK\epsilon_K and Re(ϵ/ϵK){\rm Re} (\epsilon' / \epsilon_K) can be accommodated for relatively large tanβ\tan\beta without any fine tunings or contradictions to the FCNC and EDM constraints.Comment: Contribution to the Proceedings of ICHEP2000, Osaka, 200
    corecore