5,374 research outputs found

    The NASA SBIR product catalog

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    The purpose of this catalog is to assist small business firms in making the community aware of products emerging from their efforts in the Small Business Innovation Research (SBIR) program. It contains descriptions of some products that have advanced into Phase 3 and others that are identified as prospective products. Both lists of products in this catalog are based on information supplied by NASA SBIR contractors in responding to an invitation to be represented in this document. Generally, all products suggested by the small firms were included in order to meet the goals of information exchange for SBIR results. Of the 444 SBIR contractors NASA queried, 137 provided information on 219 products. The catalog presents the product information in the technology areas listed in the table of contents. Within each area, the products are listed in alphabetical order by product name and are given identifying numbers. Also included is an alphabetical listing of the companies that have products described. This listing cross-references the product list and provides information on the business activity of each firm. In addition, there are three indexes: one a list of firms by states, one that lists the products according to NASA Centers that managed the SBIR projects, and one that lists the products by the relevant Technical Topics utilized in NASA's annual program solicitation under which each SBIR project was selected

    Precision Measurements of the Semileptonic Charm Decays D0π+νD^0 \to \pi^- \ell^+ \nu and D0K+νD^0 \to K^- \ell^+ \nu

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    We investigate the decays D0π+νD^0\to\pi^-\ell^+\nu and D0K+νD^0\to K^-\ell^+ \nu, where \ell is ee or μ\mu, using approximately 7 fb1{\rm fb}^{-1} of data collected with the CLEO III detector. We find R0B(D0πe+ν)/B(D0Ke+ν)=0.082±0.006±0.005R_0\equiv {\cal B}(D^0\to \pi^-e^+\nu)/{\cal B}(D^0\to K^-e^+\nu)= 0.082 \pm 0.006 \pm 0.005. Fits to the kinematic distributions of the data provide parameters describing the form factor of each mode. Combining the form factor results and R0R_0 gives f+π(0)2Vcd2/f+K(0)2Vcs2=0.0380.0070.003+0.006+0.005|f^{\pi}_{+}(0)|^2 |V_{cd}|^2/|f^K_{+}(0)|^2 |V_{cs}|^2 = 0.038^{+0.006+0.005}_{-0.007-0.003}.Comment: 5 pages, 2 figures, talk given at DPF'04, UC Riverside, C

    NASA SBIR abstracts of 1991 phase 1 projects

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    The objectives of 301 projects placed under contract by the Small Business Innovation Research (SBIR) program of the National Aeronautics and Space Administration (NASA) are described. These projects were selected competitively from among proposals submitted to NASA in response to the 1991 SBIR Program Solicitation. The basic document consists of edited, non-proprietary abstracts of the winning proposals submitted by small businesses. The abstracts are presented under the 15 technical topics within which Phase 1 proposals were solicited. Each project was assigned a sequential identifying number from 001 to 301, in order of its appearance in the body of the report. Appendixes to provide additional information about the SBIR program and permit cross-reference of the 1991 Phase 1 projects by company name, location by state, principal investigator, NASA Field Center responsible for management of each project, and NASA contract number are included

    NASA SBIR abstracts of 1990 phase 1 projects

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    The research objectives of the 280 projects placed under contract in the National Aeronautics and Space Administration (NASA) 1990 Small Business Innovation Research (SBIR) Phase 1 program are described. The basic document consists of edited, non-proprietary abstracts of the winning proposals submitted by small businesses in response to NASA's 1990 SBIR Phase 1 Program Solicitation. The abstracts are presented under the 15 technical topics within which Phase 1 proposals were solicited. Each project was assigned a sequential identifying number from 001 to 280, in order of its appearance in the body of the report. The document also includes Appendixes to provide additional information about the SBIR program and permit cross-reference in the 1990 Phase 1 projects by company name, location by state, principal investigator, NASA field center responsible for management of each project, and NASA contract number

    Measure of the size of CP violation in extended models

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    In this letter we introduce a possible measure of the size of CP violation in the Standard Model and its extensions, based on quantities invariant under the change of weak quark basis. We also introduce a measure of the ``average size'' of CP violation in a model, which can be used to compare the size of CP violation in models involving extra sequential or vector-like quarks, or left-right symmetry.Comment: LaTeX, 7 pages, no figure

    Factorization Contributions and the Breaking of the ΔI=1/2\Delta I=1/2 Rule in Weak ΛNρ\Lambda N\rho and ΣNρ\Sigma N\rho Couplings

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    We compute the modified factorization contributions to the ΛNρ\Lambda\rightarrow N\rho and ΣNρ\Sigma\rightarrow N\rho couplings and demonstrate that these contributions naturally include ΔI=3/2\Delta I=3/2 terms which are comparable (0.4\simeq 0.4 to 0.8-0.8 times) in magnitude to the corresponding ΔI=1/2\Delta I=1/2 terms. As a consequence, we conclude that models which treat vector meson exchange contributions to the weak conversion process ΛNNN\Lambda N\rightarrow NN assuming such weak couplings to satisfy the ΔI=1/2\Delta I=1/2 rule are unlikely to be reliable.Comment: 13 pages, uses REVTEX Entire manuscript available as a ps file at http://www.physics.adelaide.edu.au/theory/home.html . Also available via anonymous ftp at ftp://adelphi.adelaide.edu.au/pub/theory/ADP-95-5.T172.ps To appear in Physical Review

    QCD and the Chiral Critical Point

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    As an extension of QCDQCD, consider a theory with ``2+12+1'' flavors, where the current quark masses are held in a fixed ratio as the overall scale of the quark masses is varied. At nonzero temperature and baryon density it is expected that in the chiral limit the chiral phase transition is of first order. Increasing the quark mass from zero, the chiral transition becomes more weakly first order, and can end in a chiral critical point. We show that the only massless field at the chiral critical point is a sigma meson, with the universality class that of the Ising model. Present day lattice simulations indicate that QCDQCD is (relatively) near to the chiral critical point.Comment: 7 pages + 2 figures, BNL-GGP-

    On a zero speed sensitive cellular automaton

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    Using an unusual, yet natural invariant measure we show that there exists a sensitive cellular automaton whose perturbations propagate at asymptotically null speed for almost all configurations. More specifically, we prove that Lyapunov Exponents measuring pointwise or average linear speeds of the faster perturbations are equal to zero. We show that this implies the nullity of the measurable entropy. The measure m we consider gives the m-expansiveness property to the automaton. It is constructed with respect to a factor dynamical system based on simple "counter dynamics". As a counterpart, we prove that in the case of positively expansive automata, the perturbations move at positive linear speed over all the configurations

    SU(3) Decomposition of Two-Body B Decay Amplitudes

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    We present the complete flavor SU(3) decomposition of decay amplitudes for decays of the triplet (B^+_u, B^0_d, B^0_s) of B mesons nonleptonically into two pseudoscalar mesons. This analysis holds for arbitrarily broken SU(3) and can be used to generate amplitude relations when physical arguments permit one to neglect or relate any of the reduced amplitudes.Comment: 31 pages, revtex, no figure

    τρππν\tau\to\rho\pi\pi\nu decays

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    Effective chiral theory of mesons is applied to study the four decay modes of τρππν\tau\to\rho\pi\pi\nu. Theoretical values of the branching ratios are in agreement with the data. The theory predicts that the a1a_{1} resonance plays a dominant role in these decays. There is no new parameter in this study.Comment: 12 pages and one figur
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