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The yield curve for the54Fe(p, γ)55Co reaction in the energy regionE p=1.5–2.9 MeV has been recorded and the decay of ten resonances has been investigated. For six of the resonances the strengths have been determined. The angular distributions of the gamma rays have been recorded for four resonances to obtain spins or spin limitations for excited levels. In addition the lifetimes of 10 bound levels were determined with the Doppler Shift Attenuation Method. The isobaric analogues of the ground state and five excited states in55Fe are discussed.  相似文献   
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Energy levels in 153Er have been populated in the reaction 144Sm(12C. 3n)153Er. Isotopically enriched targets were bombarded with 53–65 MeV 12C ions and the emitted γ-ray and conversion electron spectra were investigated. From studies of excitation functions. γ- coincidences, γ-ray multiplicities, delayed γ-radiation and angular distributions, the level scheme of 153Er has been constructed. The properties of the energy levels are discussed and compared with the results of calculations with a deformed shell model. The remarkable similarities and some important discrepancies of the level structure, when compared with adjacent, N = 85 nuclides, are emphasized.  相似文献   
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Entanglement evolution is studied in open systems represented by rings of qubits with the Ising interaction and variously oriented external field and with Markov environments. The effect of thermal or dephasing environment is manifested as exponential decrease of the entanglement superposed on its dynamics in the isolated system.  相似文献   
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The59Co(p, γ)60Ni reaction has been investigated in the proton energy regionE p=1365–2150 keV. Decay schemes and branching ratios have been determined for ten resonances, five of which have been identified as possible analogues or fragments of analogues of the ground state (5+) and the 58.6 keV (2+), 277.1 keV (4+), 288.4 keV (3+), and 435.7 keV (5+) levels in60Co. At eight of the resonances most of the decay seems to go via a group of states with an excitation energy of 5–9 MeV. The investigated analogue states give a Coulomb displacement energy of 9118±7 keV.  相似文献   
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The “iterative instrumental variables” (IIV) method for estimating interdependent systems, originally referred to as a symmetric counterpart to the “fix-point” (FP) method, shares its symmetry properties with Durbin's iterative method for performing the “full information maximum likelihood” (FIML) estimation. Classical interdependent systems are considered and identities may occur among the structural equations. Alternative symmetric procedures for obtaining FIML estimates are also dealt with, including the sequential maximization of the likelihood function with respect to the coefficients of one structural equation at a time.Two recent estimation methods developed by Brundy and Jorgenson (1971, Review of Economics and Statistics53, 207–224) as well as Dhrymes (1971, Austral. J. Statist.13, 168–175) can be considered the second approximation of the IIV method and Durbin's method respectively with the first approximation obtained by the “ordinary instrumental variables” (OIV) method. In practice the second approximation depends heavily on the choice of initial instrumental variables, although the asymptotic distribution is not changed by the continued iteration.  相似文献   
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