MiniBooNE Collaboration(Aguilar-Arevalo, A. A. et al), & Sorel, M. (2011). Measurement of neutrino-induced charged-current charged pion production cross sections on mineral oil at E-nu similar to 1 GeV. Phys. Rev. D, 83(5), 052007–26pp.
Abstract: Using a high-statistics, high-purity sample of nu(mu)-induced charged current, charged pion events in mineral oil (CH2), MiniBooNE reports a collection of interaction cross sections for this process. This includes measurements of the CC pi+ cross section as a function of neutrino energy, as well as flux-averaged single-and double-differential cross sections of the energy and direction of both the final-state muon and pion. In addition, each of the single-differential cross sections are extracted as a function of neutrino energy to decouple the shape of the MiniBooNE energy spectrum from the results. In many cases, these cross sections are the first time such quantities have been measured on a nuclear target and in the 1 GeV energy range.
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BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Measurement of partial branching fractions of inclusive charmless B meson decays to K+, K-0, and pi(+). Phys. Rev. D, 83(3), 031103–8pp.
Abstract: We present measurements of partial branching fractions of B -> K+ X, B -> (KX)-X-0, and B -> pi(+) X, where X denotes any accessible final state above the endpoint for B decays to charmed mesons, specifically for momenta of the candidate hadron greater than 2.34 (2.36) GeV for kaons (pions) in the B rest frame. These measurements are sensitive to potential new-physics particles which could enter the b -> s(d) loop transitions. The analysis is performed on a data sample consisting of 383 X 10(6)B (B) over bar pairs collected with the BABAR detector at the PEP-II e(+)e(-) asymmetric energy collider. We observe the inclusive B -> pi(+) X process, and we set upper limits for B -> K+ X and B -> (KX)-X-0. Our results for these inclusive branching fractions are consistent with those of known exclusive modes, and exclude large enhancements due to sources of new physics.
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BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Analysis of the D+ -> K- pi(+) e(+) nu(e) decay channel. Phys. Rev. D, 83(7), 072001–35pp.
Abstract: Using 347: 5 fb(-1) of data recorded by the BABAR detector at the PEP-II electron-positron collider, 244 x 10(3) signal events for the D+ -> K- pi(+)e(+)nu(e) decay channel are analyzed. This decay mode is dominated by the (K) over bar*(892)(0) contribution. We determine the (K) over bar*(892)(0) parameters: m(K*(892)0) (895.4 +/- 0.2 +/- 0.2) MeV/c(2),Gamma(0)(K*(892)0) (46.5 +/- 0.3 +/- 0.2) MeV/c(2), and the Blatt-Weisskopf parameter r(BW) = 2.1 +/- 0.5 +/- 0.5 (GeV/c)(-1), where the first uncertainty comes from statistics and the second from systematic uncertainties. We also measure the parameters defining the corresponding hadronic form factors at q(2) = 0 (r(V) = V(0)/A(1)(0) = 1.463 +/- 0.031, r(2) = A(2)(0)/A(1)(0) = 0.801 +/- 0.020 +/- 0.020) and the value of the axial-vector pole mass parametrizing the q(2) variation of A(1) and A(2): m(A) (2.63 +/- 0.10 +/- 0.13) GeV/c(2). The S-wave fraction is equal to (5.79 +/- 0.16 +/- 0: 15)%. Other signal components correspond to fractions below 1%. Using the D+ -> K-pi(+)pi(+) channel as a normalization, we measure the D+ semileptonic branching fraction: B(D+ K-pi(+)e(+)nu(e)) (4.00 +/- 0: 03 +/- 0.04 +/- 0.09) x 10(-2), where the third uncertainty comes from external inputs. We then obtain the value of the hadronic form factor A(1) at q(2) 0: A(1)(0) 0.6200 +/- 0.0056 +/- 0.0065 +/- 0.0071. Fixing the P-wave parameters, we measure the phase of the S wave for several values of the K pi mass. These results confirm those obtained with K pi production at small momentum transfer in fixed target experiments.
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Roszkowski, L., Ruiz de Austri, R., Trotta, R., Tsai, Y. L. S., & Varley, T. A. (2011). Global fits of the nonuniversal Higgs model. Phys. Rev. D, 83(1), 015014–19pp.
Abstract: We carry out global fits to the nonuniversal Higgs Model (NUHM), applying all relevant present-day constraints. We present global probability maps for the NUHM parameters and observables (including collider signatures, direct, and indirect detection quantities), both in terms of posterior probabilities and in terms of profile likelihood maps. We identify regions of the parameter space where the neutralino dark matter in the model is either binolike, or else higgsinolike with mass close to 1 TeV and a spin-independent scattering cross section similar to 10(-9)-10(-8) pb. We trace the occurrence of the higgsinolike region to be a consequence of a mild focusing effect in the running of one of the Higgs masses, the existence of which in the NUHM we identify in our analysis. Although the usual binolike neutralino is more prominent, higgsinolike dark matter cannot be excluded, however its significance strongly depends on the prior and statistics used to assess it. We note that, despite experimental constraints often favoring different regions of parameter space to the constrained minimal supersymmetric standard model, most observational consequences appear fairly similar, which will make it challenging to distinguish the two models experimentally.
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Bertolini, S., Di Luzio, L., & Malinsky, M. (2011). Minimal flipped SO(10) x U(1) supersymmetric Higgs model. Phys. Rev. D, 83(3), 035002–28pp.
Abstract: We investigate the conditions on the Higgs sector that allow supersymmetric SO(10) grand unified theories to break spontaneously to the standard electroweak model at the renormalizable level. If one considers Higgs representations of dimension up to the adjoint, a supersymmetric standard model vacuum requires, in most cases, the presence of nonrenormalizable operators. The active role of Planck-induced nonrenormalizable operators in the breaking of the gauge symmetry introduces a hierarchy in the mass spectrum at the grand unified theory scale that may be an issue for gauge unification and proton decay. We show that the minimal Higgs scenario that allows for a renormalizable breaking to the standard model is obtained by considering flipped SO(10) circle times U(1) with one adjoint (45(H)) and two pairs of 16(H) circle plus (16) over bar (H) Higgs representations. We consider a nonanomalous matter content and discuss the embedding of the model in an E-6 grand unified scenario just above the flipped SO(10) scale.
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