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Bordes, J., Chan, H. M., & Tsun, T. S. (2010). Possible anomalies in Higgs decay: charm-suppression and flavour-violation. Eur. Phys. J. C, 65(3-4), 537–542.
Abstract: It is suggested that the Higgs boson may have a branching ratio into the c (c) over bar c mode suppressed by several orders of magnitude compared with conventional predictions and in addition some small but detectable flavour-violating modes such as b (s) over bar and tau(mu) over bar. The suggestion is based on a scheme proposed and tested earlier for explaining the mixing pattern and mass hierarchy of fermions in terms of a rotating mass matrix. If confirmed, the effects would cast new light on the geometric origin of fermion generations and of the Higgs field itself.
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MiniBooNE Collaboration(Aguilar-Arevalo, A. A. et al), & Sorel, M. (2010). Measurement of the neutrino neutral-current elastic differential cross section on mineral oil at E-nu similar to 1 GeV. Phys. Rev. D, 82(9), 092005–16pp.
Abstract: We report a measurement of the flux-averaged neutral-current elastic differential cross section for neutrinos scattering on mineral oil (CH2) as a function of four-momentum transferred squared, Q(2). It is obtained by measuring the kinematics of recoiling nucleons with kinetic energy greater than 50 MeV which are readily detected in MiniBooNE. This differential cross-section distribution is fit with fixed nucleon form factors apart from an axial mass M-A that provides a best fit for M-A = 1.39 +/- 0.11 GeV. Using the data from the charged-current neutrino interaction sample, a ratio of neutral-current to charged-current quasielastic cross sections as a function of Q(2) has been measured. Additionally, single protons with kinetic energies above 350 MeV can be distinguished from neutrons and multiple nucleon events. Using this marker, the strange quark contribution to the neutral-current axial vector form factor at Q(2) – 0, Delta s, is found to be Delta s = 0.08 +/- 0.26.
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Yamagata-Sekihara, J., Cabrera, D., Vicente Vacas, M. J., & Hirenzaki, S. (2010). Formation of phi Mesic Nuclei. Prog. Theor. Phys., 124(1), 147–162.
Abstract: We consider the structure and formation of the phi mesic nuclei to investigate the experimental feasibility of the observation of signals of the phi mesic nucleus formation. phi mesic nuclei are considered to be very important objects to study the in-medium modification of the phi-meson spectral function at finite density. We consider ((p) over bar, phi), (gamma, p) and (pi(-), n) reactions to produce a phi-meson inside the nucleus and evaluate the effects of its medium modifications to the reaction cross sections. We also estimate the consequences of the uncertainties of the in-medium (K) over bar self-energy to the phi-nucleus interaction. We find that it may be possible to see peak structures in the reaction spectra for the strong attractive potential cases. On the other hand, for strong absorptive interaction cases with relatively weak attraction, it is very difficult to observe clear peaks and we may need to know the spectrum shape in a wide energy region to deduce the properties of phi.
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MiniBooNE Collaboration(Aguilar-Arevalo, A. A. et al), & Sorel, M. (2010). Event Excess in the MiniBooNE Search for (nu)over-bar(mu) -> (nu)over-bar(e) Oscillations. Phys. Rev. Lett., 105(18), 181801–5pp.
Abstract: The MiniBooNE experiment at Fermilab reports results from a search for (nu) over bar (mu) -> (nu) over bar (e) oscillations, using a data sample corresponding to 5.66 x 10(20) protons on target. An excess of 20.9 +/- 14.0 events is observed in the energy range 475 < E-nu(QE) < 1250 MeV, which, when constrained by the observed <(nu)over bar>(mu) events, has a probability for consistency with the background-only hypothesis of 0.5%. On the other hand, fitting for (nu) over bar (mu) -> (nu) over bar (e) oscillations, the best-fit point has chi(2) probability of 8.7%. The data are consistent with (nu) over bar (mu) -> (nu) over bar (e) oscillations in the 0.1 to 1.0 eV(2) Delta m(2) range and with the evidence for antineutrino oscillations from the Liquid Scintillator Neutrino Detector at Los Alamos National Laboratory.
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MiniBooNE Collaboration(Aguilar-Arevalo, A. A. et al), & Sorel, M. (2010). First measurement of the muon neutrino charged current quasielastic double differential cross section. Phys. Rev. D, 81(9), 092005–22pp.
Abstract: A high-statistics sample of charged-current muon neutrino scattering events collected with the MiniBooNE experiment is analyzed to extract the first measurement of the double differential cross section (d(2)sigma/dT(mu)dcos theta(mu)) for charged-current quasielastic (CCQE) scattering on carbon. This result features minimal model dependence and provides the most complete information on this process to date. With the assumption of CCQE scattering, the absolute cross section as a function of neutrino energy (sigma[E-nu]) and the single differential cross section (d sigma/dQ(2)) are extracted to facilitate comparison with previous measurements. These quantities may be used to characterize an effective axial-vector form factor of the nucleon and to improve the modeling of low-energy neutrino interactions on nuclear targets. The results are relevant for experiments searching for neutrino oscillations.
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