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MiniBooNE Collaboration(Aguilar-Arevalo, A. A. et al), & Sorel, M. (2011). Measurement of nu(mu)-induced charged-current neutral pion production cross sections on mineral oil at E-nu is an element of 0.5-2.0 GeV. Phys. Rev. D, 83(5), 052009–17pp.
Abstract: Using a custom 3-Cerenkov ring fitter, we report cross sections for nu(mu)-induced charged-current single pi(0) production on mineral oil (CH2) from a sample of 5810 candidate events with 57% signal purity over an energy range of 0.5-2.0 GeV. This includes measurements of the absolute total cross section as a function of neutrino energy, and flux-averaged differential cross sections measured in terms of Q(2), mu(-) kinematics, and pi(0) kinematics. The sample yields a flux-averaged total cross section of (9.2 +/- 0.3(stat) +/- 1.5(syst)) X 10(-39) cm(2)/CH2 at mean neutrino energy of 0.965 GeV.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2011). Measurement of the t(t)over-bar production cross section with an in situ calibration of b-jet identification efficiency. Phys. Rev. D, 83(7), 071102–8pp.
Abstract: A measurement of the top-quark pair-production cross section in p (p) over bar collisions at root s = 1.96 TeV using data corresponding to an integrated luminosity of 1.12 fb(-1) collected with the Collider Detector at Fermilab is presented. Decays of top-quark pairs into the final states ev + jets and μv+ jets are selected, and the cross section and the b-jet identification efficiency are determined using a new measurement technique which requires agreement between the measured cross sections with exactly one and with multiple identified b quarks from the top-quark decays. Assuming a top-quark mass of 175 GeV/c(2), a cross section of 8.5 +/- 0.6(stat) +/- 0.7(syst)pb is measured.
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Jung, M., Pich, A., & Tuzon, P. (2011). B(bar) -> X_s gamma rate and CP asymmetry within the aligned two-Higgs-doublet model. Phys. Rev. D, 83(7), 074011–8pp.
Abstract: In the two-Higgs-doublet model the alignment of the Yukawa matrices in flavor space guarantees the absence of flavor-changing neutral currents at tree level, while introducing new sources for CP violation parametrized in a very economical way [Antonio Pich and Paula Tuzon, Phys. Rev. D 80, 091702 (2009)]. This implies a potentially large influence in a number of processes, b -> s gamma being a prominent example where rather high experimental and theoretical precision meet. We analyze the CP rate asymmetry in this inclusive decay and determine the resulting constraints on the model parameters. We demonstrate the compatibility with previously obtained limits [Martin Jung, Antonio Pich, and Paula Tuzon, J. High Energy Phys. 11 (2010) 003]. Moreover, we extend the phenomenological analysis of the branching ratio, and examine the influence of resulting correlations on the like-sign dimuon charge asymmetry in B decays.
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Bodenstein, S., Bordes, J., Dominguez, C. A., Peñarrocha, J., & Schilcher, K. (2011). QCD sum rule determination of the charm-quark mass. Phys. Rev. D, 83(7), 074014–4pp.
Abstract: QCD sum rules involving mixed inverse moment integration kernels are used in order to determine the running charm-quark mass in the (MS) over bar scheme. Both the high and the low energy expansion of the vector current correlator are involved in this determination. The optimal integration kernel turns out to be of the form p(s) = 1 -(s(0)/s)(2), where s(0) is the onset of perturbative QCD. This kernel enhances the contribution of the well known narrow resonances, and reduces the impact of the data in the range s similar or equal to 20-25 GeV2. This feature leads to a substantial reduction in the sensitivity of the results to changes in s(0), as well as to a much reduced impact of the experimental uncertainties in the higher resonance region. The value obtained for the charm-quark mass in the (MS) over bar scheme at a scale of 3 GeV is (m) over bar (c)(3 GeV) = 987 +/- 9 MeV, where the error includes all sources of uncertainties added in quadrature.
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Pato, M., Baudis, L., Bertone, G., Ruiz de Austri, R., Strigari, L. E., & Trotta, R. (2011). Complementarity of dark matter direct detection targets. Phys. Rev. D, 83(8), 083505–11pp.
Abstract: We investigate the reconstruction capabilities of the dark matter mass and spin-independent cross section from future ton-scale direct detection experiments using germanium, xenon, or argon as targets. Adopting realistic values for the exposure, energy threshold, and resolution of dark matter experiments which will come online within 5 to 10 years, the degree of complementarity between different targets is quantified. We investigate how the uncertainty in the astrophysical parameters controlling the local dark matter density and velocity distribution affects the reconstruction. For a 50 GeV WIMP, astrophysical uncertainties degrade the accuracy in the mass reconstruction by up to a factor of similar to 4 for xenon and germanium, compared to the case when astrophysical quantities are fixed. However, the combination of argon, germanium, and xenon data increases the constraining power by a factor of similar to 2 compared to germanium or xenon alone. We show that future direct detection experiments can achieve self-calibration of some astrophysical parameters, and they will be able to constrain the WIMP mass with only very weak external astrophysical constraints.
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Pierre Auger Collaboration(Abreu, P. et al), & Pastor, S. (2011). Advanced functionality for radio analysis in the Offline software framework of the Pierre Auger Observatory. Nucl. Instrum. Methods Phys. Res. A, 635(1), 92–102.
Abstract: The advent of the Auger Engineering Radio Array (AERA) necessitates the development of a powerful framework for the analysis of radio measurements of cosmic ray air showers. As AERA performs “radio-hybrid” measurements of air shower radio emission in coincidence with the surface particle detectors and fluorescence telescopes of the Pierre Auger Observatory, the radio analysis functionality had to be incorporated in the existing hybrid analysis solutions for fluorescence and surface detector data. This goal has been achieved in a natural way by extending the existing Auger Offline software framework with radio functionality. In this article, we lay out the design, highlights and features of the radio extension implemented in the Auger Offline framework. Its functionality has achieved a high degree of sophistication and offers advanced features such as vectorial reconstruction of the electric field, advanced signal processing algorithms, a transparent and efficient handling of FFTs, a very detailed simulation of detector effects, and the read-in of multiple data formats including data from various radio simulation codes. The source code of this radio functionality can be made available to interested parties on request.
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BABAR Collaboration(del Amo Sanchez, P. et al), Azzolini, V., Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2011). Study of B -> pi lv and B -> rho lv decays and determination of |Vub|. Phys. Rev. D, 83(3), 032007–45pp.
Abstract: We present an analysis of exclusive charmless semileptonic B-meson decays based on 377 x 10(6) B (B) over bar pairs recorded with the BABAR detector at the Y(4S) resonance. We select four event samples corresponding to the decay modes B-0 -> pi(-)l(+)v, B+ -> pi(0)l(+)v, B-0 -> rho(-)l(+)v, and B+ -> rho(0)l(+)v and find the measured branching fractions to be consistent with isospin symmetry. Assuming isospin symmetry, we combine the two B -> pi lv samples, and similarly the two B -> rho lv samples, and measure the branching fractions B(B-0 -> pi(-)l(+)v) = (1.41 +/- 0.05 +/- 0.07) x 10(-4) and B(B-0 -> rho(-)l(+)v) = (1.75 +/- 0.15 +/- 0.27) x 10(-4), where the errors are statistical and systematic. We compare the measured distribution in q(2), the momentum transfer squared, with predictions for the form factors from QCD calculations and determine the Cabibbo-Kobayashi-Maskawa matrix element vertical bar V-ub vertical bar. Based on the measured partial branching fraction for B -> pi lv in the range q(2) < 12 GeV2 and the most recent QCD light-cone sum-rule calculations, we obtain vertical bar V-ub vertical bar = (3.78 +/- 0.13(-0.40)(+0.55)10(-3), where the errors refer to the experimental and theoretical uncertainties. From a simultaneous fit to the data over the full q(2) range and the FNAL/MILC lattice QCD results, we obtain vertical bar V-ub vertical bar = (2.95 +/- 0.31) x 10(-3) from B -> pi lv, where the error is the combined experimental and theoretical uncertainty.
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Blennow, M., Dasgupta, B., Fernandez-Martinez, E., & Rius, N. (2011). Aidnogenesis via leptogenesis and dark sphalerons. J. High Energy Phys., 03(3), 014–14pp.
Abstract: We discuss aidnogenesis,(1) i.e. the generation of a dark matter asymmetry, via new sphaleron processes associated to an extra non-abelian gauge symmetry common to both the visible and the dark sectors. Such a theory can naturally produce an abundance of asymmetric dark matter which is of the same size as the lepton and baryon asymmetries, as suggested by the similar sizes of the observed baryonic and dark matter energy content, and provide a definite prediction for the mass of the dark matter particle. We discuss in detail a minimal realization in which the Standard Model is only extended by dark matter fermions which form “dark baryons” through an SU(3) interaction, and a (broken) horizontal symmetry that induces the new sphalerons. The dark matter mass is predicted to be similar to 6GeV, close to the region favored by DAMA and CoGeNT. Furthermore, a remnant of the horizontal symmetry should be broken at a lower scale and can also explain the Tevatron dimuon anomaly.
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SciBooNE Collaboration(Nakajima, Y. et al), Catala-Perez, J., Gomez-Cadenas, J. J., & Sorel, M. (2011). Measurement of inclusive charged current interactions on carbon in a few-GeV neutrino beam. Phys. Rev. D, 83(1), 012005–21pp.
Abstract: We report a measurement of inclusive charged current interactions of muon neutrinos on carbon with an average energy of 0.8 GeV using the Fermilab Booster Neutrino Beam. We compare our measurement with two neutrino interaction simulations: NEUT and NUANCE. The charged current interaction rates (product of flux and cross section) are extracted by fitting the muon kinematics, with a precision of 6%-15% for the energy dependent and 3% for the energy integrated analyses. We also extract charged current inclusive interaction cross sections from the observed rates, with a precision of 10%-30% for the energy dependent and 8% for the energy integrated analyses. This is the first measurement of the charged current inclusive cross section on carbon around 1 GeV. These results can be used to convert previous SciBooNE cross-section ratio measurements to absolute cross-section values.
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Calabrese, E., de Putter, R., Huterer, D., Linder, E. V., & Melchiorri, A. (2011). Future CMB constraints on early, cold, or stressed dark energy. Phys. Rev. D, 83(2), 023011–11pp.
Abstract: We investigate future constraints on early dark energy (EDE) achievable by the Planck and CMBPol experiments, including cosmic microwave background (CMB) lensing. For the dark energy, we include the possibility of clustering through a sound speed c(s)(2) < 1 (cold dark energy) and anisotropic stresses parametrized with a viscosity parameter c(vis)(2). We discuss the degeneracies between cosmological parameters and EDE parameters. In particular we show that the presence of anisotropic stresses in EDE models can substantially undermine the determination of the EDE sound speed parameter c(s)(2). The constraints on EDE primordial energy density are however unaffected. We also calculate the future CMB constraints on neutrino masses and find that they are weakened by a factor of 2 when allowing for the presence of EDE, and highly biased if it is incorrectly ignored.
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