1,557 research outputs found

    Coulomb breakup effects on the elastic cross section of 6^6He+209^{209}Bi scattering near Coulomb barrier energies

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    We accurately analyze the 6^6He+209^{209}Bi scattering at 19 and 22.5 MeV near the Coulomb barrier energy, using the continuum-discretized coupled-channels method (CDCC) based on the nn+nn+4^4He+209^{209}Bi four-body model. The three-body breakup continuum of 6^6He is discretized by diagonalizing the internal Hamiltonian of 6^6He in a space spanned by the Gaussian basis functions. The calculated elastic and total reaction cross sections are in good agreement with the experimental data, while the CDCC calculation based on the di-neutron model of 6^6He, i.e., the 2n^2n+4^{4}He+209^{209}Bi three-body model, does not reproduce the data.Comment: 5 pages, 5 figures, uses REVTeX 4, submitted to Phys. Rev.

    Stau-catalyzed 6^6Li Production in Big-Bang Nucleosynthesis

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    If the gravitino mass is in the region from a few GeV to a few 10's GeV, the scalar lepton X such as stau is most likely the next lightest supersymmetry particle. The negatively charged and long-lived X^- may form a Coulomb bound state (A X) with a nucleus A and may affect the big-bang nucleosynthesis through catalyzed fusion process. We calculate a production cross section of Li6 from the catalyzed fusion (He4 X^-) + d \to Li6 + X^- by solving the Schr\"{o}dinger equation exactly for three-body system of He4, d, and X. We utilize the state-of-the-art coupled-channel method, which is known to be very accurate to describe other three-body systems in nuclear and atomic reactions. The importance of the use of appropriate nuclear potential and the exact treatment of the quantum tunneling in the fusion process are emphasized. We find that the astrophysical S-factor at the Gamow peak corresponding to T=10 keV is 0.038 MeV barn. This leads to the Li6 abundance from the catalyzed process as Li6|_{CBBN}\simeq 4.3\times 10^{-11} (D/2.8\times 10^{-5}) ([n_{X^-}/s]/10^{-16}) in the limit of long lifetime of X. Particle physics implication of this result is also discussed.Comment: 16 pages, 7 figure

    Light Ξ\Xi hypernuclei in four-body cluster models

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    Detailed structure calculations in Ξ− 12^{\: 12}_{\Xi^-}Be, Ξ− 5^{\: 5}_{\Xi^-}H, Ξ− 9^{\: 9}_{\Xi^-}Li, Ξ− 7^{\: 7}_{\Xi^-}H and Ξ− 10^{\:10}_{\Xi^-}Li are performed within the framework of the microscopic two-, three- and four-body cluster models using the Gaussian Expansion Method.Comment: 14 pages, 19 figures. To be published in Phys. Rev.

    Glycemic control in a 79-year-old female with mild cognitive impairment using a medication reminder device: a case report

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    A 79-year-old female with type 2 diabetes and mild cognitive impairment (Clinical Dementia Rating score of 0.5) was supported with medication with regard to the daily requirements using a medication reminder device. Use of this device not only improved her medication adherence, hemoglobin A1c level, and self-confidence but also reduced caregiver's burden. For elderly patients with such diseases, loading the device with medication, providing advance notice before mechanical reminders for a short period after the device's activation, monitoring unused medication, and adjusting the timing of reminders according to users' daily routine, seemed to facilitate daily use of the device.ArticleINTERNATIONAL PSYCHOGERIATRICS. 26(6):1045-1048 (2014)journal articl

    Phonon density of states and compression behavior in iron sulfide under pressure

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    We report the partial phonon densities of states (DOS) of iron sulfide, a possible component of the rocky planet's core, measured by the Fe-57 nuclear resonant inelastic x-ray scattering and calculate the total phonon DOS under pressure. From the phonon DOS, we drive thermodynamic parameters. A comparison of the observed and estimated compressibilities makes it clear that there is a large pure electronic contribution in the observed compressibility in the metallic state. Our results present the observation of thermodynamic parameters of iron sulfide with the low-spin state of an Fe2+ ion at the high density, which is similar to the condition of the Martian core
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