Baker, M. J., Bordes, J., Dominguez, C. A., Peñarrocha, J., & Schilcher, K. (2014). B meson decay constants f(Bc), f(Bs) and f(B) from QCD sum rules. J. High Energy Phys., 07(7), 032–16pp.
Abstract: Finite energy QCD sum rules with Legendre polynomial integration kernels are used to determine the heavy meson decay constant f(Bc), and revisit f(B) and f(Bs). Results exhibit excellent stability in a wide range of values of the integration radius in the complex squared energy plane, and of the order of the Legendre polynomial. Results are f(Bc) = 528 +/- 19 MeV, f(B) = 186 +/- 14 MeV, and f(Bs) = 222 +/- 12 MeV.
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Balbinot, R., & Fabbri, A. (2014). Amplifying the Hawking Signal in BECs. Adv. High. Energy Phys., 2014, 713574–8pp.
Abstract: We consider simple models of Bosep-Einstein condensates to study analog pairp-creation effects, namely, the Hawking effect from acoustic black holes and the dynamical Casimir effect in rapidly timep-dependent backgrounds. We also focus on a proposal by Cornell to amplify the Hawking signal in density-density correlators by reducing the atoms' interactions shortly before measurements are made.
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Barenboim, G., Bosch, C., Lopez-Ibañez, M. L., & Vives, O. (2014). Improved tau-lepton tools for Higgs boson hunting. Phys. Rev. D, 90(1), 015003–14pp.
Abstract: In this work, we use the results from Higgs searches in the gamma gamma and tau tau decay channels at LHC and indirect bounds as BR (B -> X-s gamma) to constrain the parameter space of a generic minimal supersymmetric standard model (MSSM) Higgs sector. In particular, we include the latest CMS results that look for additional Higgs states with masses up to 1 TeV. We show that the tau tau channel is the best and most accurate tool in the hunt for new Higgs states beyond the standard model. We obtain that present experimental results rule out additional neutral Higgs bosons in a generic MSSM below 300 GeV for any value of tan beta and, for instance, values of tan beta above 30 are only possible for Higgs masses above 600 GeV. ATLAS stored data have the potential to render this bound obsolete in the near future.
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Barenboim, G., Chun, E. J., Jung, S. H., & Park, W. I. (2014). Implications of an axino LSP for naturalness. Phys. Rev. D, 90(3), 035020–12pp.
Abstract: Both the naturalness of the electroweak symmetry breaking and the resolution of the strong CP problem may require a small Higgsino mass μgenerated by a realization of the DFSZ axion model. Assuming the axino is the lightest supersymmetric particle, we study its implications on μand the axion scale. Copiously produced light Higgsinos at collider (effectively only neutral next-to-lightest superparticles pairs) eventually decay to axinos leaving prompt multileptons or displaced vertices which are being looked for at the LHC. We use latest LHC7 + 8 results to derive current limits on μand the axion scale. Various Higgsino-axino phenomenology is illustrated by comparing with a standard case without lightest axinos as well as with a more general case with additional light gauginos in the spectrum.
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Barenboim, G., Chun, E. J., & Lee, H. M. (2014). Coleman-Weinberg inflation in light of Planck. Phys. Lett. B, 730, 81–88.
Abstract: We revisit a single field inflationary model based on Coleman-Weinberg potentials. We show that in small field Coleman-Weinberg inflation, the observed amplitude of perturbations needs an extremely small quartic coupling of the inflaton, which might be a signature of radiative origin. However, the spectral index obtained in a standard cosmological scenario turns out to be outside the 2 sigma region of the Planck data. When a non-standard cosmological framework is invoked, such as brane-world cosmology in the Randall-Sundrum model, the spectral index can be made consistent with Planck data within la, courtesy of the modification in the evolution of the Hubble parameter in such a scheme. We also show that the required inflaton quartic coupling as well as a phenomenologically viable B – L symmetry breaking together with a natural electroweak symmetry breaking can arise dynamically in a generalized B – L extension of the Standard Model where the full potential is assumed to vanish at a high scale.
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