2,630 research outputs found

    The 1979 Diary Family Income and Expenditure Survey: Experience and Preliminary Results

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    This paper is presented at the Third National Convention on Statistics on December 13-14, 1982. The 1979 Diary Family income and Expenditure Survey (DFIES) has utilized the diary method of data collection to minimize, if not eliminate, errors and biases arising from the traditional recall-record method of soliciting information. Jointly conducted by the National Tax Research Center and National Census and Statistics Office, DFIES aims to provide reliable quantitative information regarding personal/additional exemptions and household income/expenditure patterns. This article argues for the utilization of DFIES in the Philippines. Areas for improvement of the system are also cited.income, data and statistics, survey method, data collection

    The 1979 Diary Family Income and Expenditure Survey: Experience and Preliminary Results

    Get PDF
    This paper is presented at the Third National Convention on Statistics on December 13-14, 1982. The 1979 Diary Family income and Expenditure Survey (DFIES) has utilized the diary method of data collection to minimize, if not eliminate, errors and biases arising from the traditional recall-record method of soliciting information. Jointly conducted by the National Tax Research Center and National Census and Statistics Office, DFIES aims to provide reliable quantitative information regarding personal/additional exemptions and household income/expenditure patterns. This article argues for the utilization of DFIES in the Philippines. Areas for improvement of the system are also cited.income, data and statistics, survey method, data collection

    Ωc\Omega_c excited states within a SU(6)lsf×{\rm SU(6)}_{\rm lsf}\timesHQSS model

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    We have reviewed the renormalization procedure used in the unitarized coupled-channel model of Phys. Rev. D85 114032 (2012), and its impact in the C=1C=1, S=−2S=-2, and I=0I=0 sector, where five Ωc(∗)\Omega_c^{(*)} states have been recently observed by the LHCb Collaboration. The meson-baryon interactions used in the model are consistent with both chiral and heavy-quark spin symmetries and lead to a successful description of the observed lowest-lying odd parity resonances Λc(2595)\Lambda_c(2595) and Λc(2625)\Lambda_c(2625), and Λb(5912)\Lambda_b(5912) and Λb(5920)\Lambda_b(5920) resonances. We show that some (probably at least three) of the states observed by LHCb will also have odd parity and spins J=1/2J=1/2 and J=3/2J=3/2, belonging two of them to the same SU(6)light−spin−flavor×{\rm SU(6)}_{\rm light-spin-flavor}\timesHQSS multiplets that the latter strangenessless heavy−Λ-\Lambda baryons.Comment: 11 pages, 3 figures, 6 tables, published in The European Physical Journal

    Large Nc Weinberg-Tomozawa interaction and negative parity s--wave baryon resonances

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    It is shown that in the 70 and 700 SU(6) irreducible spaces, the SU(6) extension of the Weinberg-Tomozawa (WT) s-wave meson-baryon interaction incorporating vector mesons ({\it hep-ph/0505233}) scales as O(Nc0){\cal O}(N_c^0), instead of the well known O(Nc−1){\cal O}(N_c^{-1}) behavior for its SU(3) counterpart. However, the WT interaction behaves as order O(Nc−1){\cal O}(N_c^{-1}) within the 56 and 1134 meson-baryon spaces. Explicit expressions for the WT couplings (eigenvalues) in the irreducible SU(2NFN_F) spaces, for arbitrary NFN_F and NcN_c, are given. This extended interaction is used as a kernel of the Bethe-Salpeter equation, to study the large NcN_c scaling of masses and widths of the lowest--lying negative parity s-wave baryon resonances. Analytical expressions are found in the Nc→∞N_c\to \infty limit, from which it can be deduced that resonance widths and excitation energies (MR−M)(M_R-M) behave as order O(Nc0){\cal O} (N^0_c), in agreement with model independent arguments, and moreover they fall in the 70-plet, as expected in constituent quark models for an orbital excitation. For the 56 and 1134 spaces, excitation energies and widths grow O(Nc1/2){\cal O} (N_c^{1/2}) indicating that such resonances do not survive in the large NcN_c limit. The relation of this latter NcN_c behavior with the existence of exotic components in these resonances is discussed. The interaction comes out repulsive in the 700.Comment: 21 pages, 3 figures, requires wick.sty and young.sty. Subsection added. Conclusions revised. To appear in Physical Review

    Resonances and the Weinberg--Tomozawa 56-baryon --35-meson interaction

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    Vector meson degrees of freedom are incorporated into the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian by using a scheme which relies on spin--flavor SU(6) symmetry. The corresponding Bethe-Salpeter approximation successfully reproduces previous SU(3)--flavor WT results for the lowest-lying s--wave negative parity baryon resonances, and it also provides some information on the dynamics of the heavier ones. Moreover, it also predicts the existence of an isoscalar spin-parity 32−\frac32^- K∗NK^*N bound state (strangeness +1) with a mass around 1.7--1.8 GeV, unstable through K∗K^* decay. Neglecting d-wave KN decays, this state turns out to be quite narrow (Γ≀15\Gamma \le 15 MeV) and it might provide clear signals in reactions like Îłp→Kˉ0pK+π−\gamma p \to \bar K^0 p K^+\pi^- by looking at the three body pK+π−p K^+\pi^- invariant mass.Comment: Talk given at the IVth International Conference on Quarks an Nuclear Physics, Madrid, June 5th-10th 2006. Minor correction

    Single photon events from neutral current interactions at MiniBooNE

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    The MiniBooNE experiment has reported results from the analysis of Îœe\nu _e and Μˉe\bar \nu _e appearance searches, which show an excess of signal-like events at low reconstructed neutrino energies, with respect to the expected background. A significant component of this background comes from photon emission induced by (anti)neutrino neutral current interactions with nucleons and nuclei. With an improved microscopic model for these reactions, we predict the number and distributions of photon events at the MiniBooNE detector. Our results are compared to the MiniBooNE in situ estimate and to other theoretical approaches. We find that, according to our model, neutral current photon emission from single-nucleon currents is insufficient to explain the events excess observed by MiniBooNE in both neutrino and antineutrino modes.Comment: 10 pages, 8 figures; error analysis improved; accepted in PL

    Meson-Baryon s-wave Resonances with Strangeness -3

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    Starting from a consistent SU(6) extension of the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian (Phys. Rev. D74 (2006) 034025), we study the s-wave meson-baryon resonances in the strangeness S=-3 and negative parity sector. Those resonances are generated by solving the Bethe-Salpeter equation with the WT interaction used as kernel. The considered mesons are those of the 35-SU(6)-plet, which includes the pseudoscalar (PS) octet of pions and the vector (V) nonet of the rho meson. For baryons we consider the 56-SU(6)-plet, made of the 1/2+ octet of the nucleon and the 3/2+ decuplet of the Delta. Quantum numbers I(J^P)=0(3/2^-) are suggested for the experimental resonances Omega*(2250)- and Omega*(2380)-. Among other, resonances with I=1 are found, with minimal quark content sss\bar{l}l', being s the strange quark and l, l' any of the the light up or down quarks. A clear signal for such a pentaquark would be a baryonic resonance with strangeness -3 and electric charge of -2 or 0, in proton charge units. We suggest looking for K- Xi- resonances with masses around 2100 and 2240 MeV in the sector 1(1/2^-), and for pi Omega- and K- Xi*- resonances with masses around 2260 MeV in the sector 1(3/2^-).Comment: 3 pages, 1 Postscript figure, 7 table

    Non-universal gravitational couplings of neutrinos in matter

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    When neutrinos travel through a normal matter medium, the electron neutrinos couple differently to gravity compared to the other neutrinos, due to the presence of electrons in the medium and the absence of the other charged leptons. The matter-induced gravitational couplings of the neutrinos under such conditions are calculated and their contribution to the neutrino index of refraction in the presence of a gravitational potential is determined.Comment: Latex, 10 page

    Exotic dynamically generated baryons with C=−=-1

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    We follow a model based on the SU(8) symmetry for the interaction of mesons with baryons. The model treats on an equal footing the pseudo-scalars and the vector mesons, as required by heavy quark symmetry. The T-matrix calculated within an unitary scheme in coupled channels has poles which are interpreted as baryonic resonances.Comment: 5 pages. Proceedings for Chiral10 workshop, Valencia, June 21-24 201
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