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Beneke, M., Hellmann, C., & Ruiz-Femenia, P. (2013). Non-relativistic pair annihilation of nearly mass degenerate neutralinos and charginos I. General framework and S-wave annihilation. J. High Energy Phys., 03(3), 148–48pp.
Abstract: We compute analytically the tree-level annihilation rates of a collection of non-relativistic neutralino and chargino two-particle states in the general MSSM, including the previously unknown off-diagonal rates. The results are prerequisites to the calculation of the Sommerfeld enhancement in the MSSM, which will be presented in subsequent work. They can also be used to obtain concise analytic expressions for MSSM dark matter pair annihilation in the present Universe for a large number of exclusive two-particle final states.
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Strege, C., Bertone, G., Feroz, F., Fornasa, M., Ruiz de Austri, R., & Trotta, R. (2013). Global fits of the cMSSM and NUHM including the LHC Higgs discovery and new XENON100 constraints. J. Cosmol. Astropart. Phys., 04(4), 013–40pp.
Abstract: We present global fits of the constrained Minimal Supersymmetric Standard Model (cMSSM) and the Non-Universal Higgs Model (NUHM), including the most recent CMS constraint on the Higgs boson mass, 5.8 fb(-1) integrated luminosity null Supersymmetry searches by ATLAS, the new LHCb measurement of B R ((B) over bar (s) -> mu(+) mu(-)) and the 7-year WMAP dark matter relic abundance determination. We include the latest dark matter constraints from the XENON100 experiment, marginalising over astrophysical and particle physics uncertainties. We present Bayesian posterior and profile likelihood maps of the highest resolution available today, obtained from up to 350M points. We find that the new constraint on the Higgs boson mass has a dramatic impact, ruling out large regions of previously favoured cMSSM and NUHM parameter space. In the cMSSM, light sparticles and predominantly gaugino-like dark matter with a mass of a few hundred GeV are favoured. The NUHM exhibits a strong preference for heavier sparticle masses and a Higgsino-like neutralino with a mass of 1 TeV. The future ton-scale XENON1T direct detection experiment will probe large portions of the currently favoured cMSSM and NUHM parameter space. The LHC operating at 14 TeV collision energy will explore the favoured regions in the cMSSM, while most of the regions favoured in the NUHM will remain inaccessible. Our best-fit points achieve a satisfactory quality-of-fit, with p-values ranging from 0.21 to 0.35, so that none of the two models studied can be presently excluded at any meaningful significance level.
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Hellmann, C., & Ruiz-Femenia, P. (2013). Non-relativistic pair annihilation of nearly mass degenerate neutralinos and charginos II. P-wave and next-to-next-to-leading order S-wave coefficients. J. High Energy Phys., 08(8), 084–49pp.
Abstract: 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.
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Anderson, L. et al, & Mena, O. (2014). The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: measuring D-A and H at z=0.57 from the baryon acoustic peak in the Data Release 9 spectroscopic Galaxy sample. Mon. Not. Roy. Astron. Soc., 439(1), 83–101.
Abstract: We present measurements of the angular diameter distance to and Hubble parameter at z = 0.57 from the measurement of the baryon acoustic peak in the correlation of galaxies from the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey. Our analysis is based on a sample from Data Release 9 of 264 283 galaxies over 3275 square degrees in the redshift range 0.43 < z < 0.70. We use two different methods to provide robust measurement of the acoustic peak position across and along the line of sight in order to measure the cosmological distance scale. We find D-A(0.57) = 1408 +/- 45 Mpc and H(0.57) = 92.9 +/- 7.8 km s(-1) Mpc(-1) for our fiducial value of the sound horizon. These results from the anisotropic fitting are fully consistent with the analysis of the spherically averaged acoustic peak position presented in Anderson et al. Our distance measurements are a close match to the predictions of the standard cosmological model featuring a cosmological constant and zero spatial curvature.
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Ruiz de Austri, R., & Perez de los Heros, C. (2013). Impact of nucleon matrix element uncertainties on the interpretation of direct and indirect dark matter search results. J. Cosmol. Astropart. Phys., 11(11), 049–19pp.
Abstract: We study in detail the impact of the current uncertainty in nucleon matrix elements on the sensitivity of direct and indirect experimental techniques for dark matter detection. We perform two scans in the framework of the cMSSM: one using recent values of the pion-sigma term obtained from Lattice QCD, and the other using values derived from experimental measurements. The two choices correspond to extreme values quoted in the literature and reflect the current tension between different ways of obtaining information about the structure of the nucleon. All other inputs in the scans, astrophysical and from particle physics, are kept unchanged. We use two experiments, XENON100 and IceCube, as benchmark cases to illustrate our case. We find that the interpretation of dark matter search results from direct detection experiments is more sensitive to the choice of the central values of the hadronic inputs than the results of indirect search experiments. The allowed regions of cMSSM parameter space after including XENON100 constrains strongly differ depending on the assumptions on the hadronic matrix elements used. On the other hand, the constraining potential of IceCube is almost independent of the choice of these values.
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