213 research outputs found

    Non-relativistic pair annihilation of nearly mass degenerate neutralinos and charginos II. P-wave and next-to-next-to-leading order S-wave coefficients

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    This paper is a continuation of an earlier work (arXiv:1210.7928) which computed analytically the tree-level annihilation rates of a collection of non-relativistic neutralino and chargino two-particle states in the general MSSM. Here we extend the results by providing the next-to-next-to-leading order corrections to the rates in the non-relativistic expansion in momenta and mass differences, which include leading P-wave effects, in analytic form. The results are a necessary input for the calculation of the Sommerfeld-enhanced dark matter annihilation rates including short-distance corrections at next-to-next-to-leading order in the non-relativistic expansion in the general MSSM with neutralino LSP.Comment: LaTeX, 16 pages (+ 36 pages Appendix), 4 figures; v2 - new appendix with analytic results for the P-wave and rest of v^2 corrections to annihilation rates in the wino limit added, matches published versio

    On the minimality of the order p^6 chiral Lagrangian

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    A method to find relations between the operators in the mesonic Lagrangian of Chiral Perturbation Theory at order p^6 is presented. The procedure can be used to establish if the basis of operators in the Lagrangian is minimal. As an example, we apply the method to the two-flavour case in the absence of scalar and pseudo-scalar sources (s=p=0), and conclude that the minimal Lagrangian contains 27 independent operators.Comment: 14 pages, 2 figure

    New contributions to heavy quark sum rules

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    We analyse new contributions to the theoretical input in heavy quark sum rules and we show that the general theory of singularities of perturbation theory amplitudes yields the method to handle these specific features. In particular we study the inclusion of heavy quark radiation by light quarks at O(alpha_s^2) and non-symmetric correlators at O(alpha_s^3). Closely related, we also propose a solution to the construction of moments of the spectral densities at O(alpha_s^3) where the presence of massless contributions invalidates the standard approach. We circumvent this problem through a new definition of the moments, providing an infrared safe and consistent procedure.Comment: 15 pages, 3 figures. Version accepted for publication in The European Journal of Physics C; several new comments and references added, conclusions unchange

    Renormalization Group Analysis in NRQCD for Colored Scalars

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    The vNRQCD Lagrangian for colored heavy scalar fields in the fundamental representation of QCD and the renormalization group analysis of the corresponding operators are presented. The results are an important ingredient for renormalization group improved computations of scalar-antiscalar bound state energies and production rates at next-to-next-to-leading-logarithmic (NNLL) order.Comment: 19 pages, 8 figures; revtex4. References added; version to appear in Phys. Rev.

    Heavy neutralino relic abundance with Sommerfeld enhancements - a study of pMSSM scenarios

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    We present a detailed discussion of Sommerfeld enhancements in neutralino dark matter relic abundance calculations for several popular benchmark scenarios in the general MSSM. Our analysis is focused on models with heavy wino- and higgsino-like neutralino LSP and models interpolating between these two scenarios. This work is the first phenomenological application of effective field theory methods that we have developed in earlier work and that allow for the consistent study of Sommerfeld enhancements in non-relativistic neutralino and chargino co-annihilation reactions within the general MSSM, away from the pure-wino and pure-higgsino limits.Comment: 38 pages, 14 figures, 3 table
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