30,518 research outputs found

    Measuring and interpreting current permanent and transitory earnings and dividends : methods and applications / BEBR No. 815

    Get PDF
    Bibliography: p. 21-22

    Residual theory, partial adjustment, and information content on dividend payments decisions : an integration and extension / BEBR No. 760

    Get PDF
    Bibliography: p. 31-32

    Dark matter and dark gauge fields

    Full text link
    Following the unexpected theoretical discovery of a mass dimension one fermionic quantum field of spin one half, we now present first results on two _local_ versions. The Dirac and Majorana fields of the standard model of particle physics are supplemented by their natural counterparts in the dark matter sector. The possibility that a mass dimension transmuting symmetry may underlie a new standard model of particle physics is briefly suggested.Comment: This manuscript combines a plenary talk (by DVA) and an invited talk (by DS) at "Dark 2007 - Sixth International Heidelberg Conference on Dark Matter in Astro and Particle Physics (Sydney, Australia, 24th-28th September 2007)." 11 pages. v2: minor typos correcte

    Fama's hypotheses of the relationship between inflation and nominal interest rates : an international comparison

    Get PDF
    Includes bibliographical references (p. 21)

    Some effects of utility regulation on firm operating and financial strategies / BEBR No. 421

    Get PDF
    Includes bibliographical references (leaves 21-22).This paper shows that different degrees of regulation affect electric utility firm's operating and financial strategies. The analysis also provides a potential approach for testing the Averch-Johnson effect using financial information which has been neglected until this time

    Physical Parameters and Renormalization of U(1)_a x U(1)_b Models

    Get PDF
    We analize the structure of models with unbroken and spontaneously broken U(1)_a x U(1)_b gauge symmetry. We show that the quantum corrections to the 2N gauge charges, with N = #fermions + #scalars, can be absorbed in the redefinition of three independent gauge couplings (g_a,g_b and g_ab). We establish the (one-loop) conditions on the matter cotent for g_ab= = 0 (a value usually assumed in the literature) and we show that in the minimal extensions of the Standard Model with an extra U(1) symmetry the choice g_ab = 0 is not stable under radiative corrections induced by the standard Higgs fields. Moreover, g_ab = 0 to all orders seems to require an exact symmetry. The spontaneous breaking of the gauge symmetry induces further mixing between the two gauge bosons and introduces a fourth independent physical parameter. A consequence of our analysis is that the usual tree-level description with only three physical parameters (i.e., two gauge couplings and one gauge boson mixing angle) is not in general a justified zero order limit of the treatment including radiative corrections.Comment: 24 pages, tex, 1 figur

    Singlet fermionic dark matter

    Full text link
    We propose a renormalizable model of a fermionic dark matter by introducing a gauge singlet Dirac fermion and a real singlet scalar. The bridges between the singlet sector and the standard model sector are only the singlet scalar interaction terms with the standard model Higgs field. The singlet fermion couples to the standard model particles through the mixing between the standard model Higgs and singlet scalar and is naturally a weakly interacting massive particle (WIMP). The measured relic abundance can be explained by the singlet fermionic dark matter as the WIMP within this model. Collider implication of the singlet fermionic dark matter is also discussed. Predicted is the elastic scattering cross section of the singlet fermion into target nuclei for a direct detection of the dark matter. Search of the direct detection of the dark matter provides severe constraints on the parameters of our model.Comment: 12 pages, 7 figure

    Flavor symmetry breaking and scaling for improved staggered actions in quenched QCD

    Get PDF
    We present a study of the flavor symmetry breaking in the pion spectrum for various improved staggered fermion actions. To study the effects of link fattening and tadpole improvement, we use three different variants of the p4 action - p4fat3, p4fat7, and p4fat7tad. These are compared to Asqtad and also to naive staggered. To study the pattern of symmetry breaking, we measure all 15 meson masses in the 4-flavor staggered theory. The measurements are done on a quenched gauge background, generated using a one-loop improved Symanzik action with β=10/g2=7.40,7.75,\beta=10/g^2 = 7.40, 7.75, and 8.00, corresponding to lattice spacings of approximately a = .31 fm., .21 fm., and .14 fm. We also study how the lattice scale set by the ρ\rho mass on each of these ensembles compares to one set by the static quark potential.Comment: 18 pages, 6 figure
    corecore