Large-Theta(13) Perturbation Theory of Neutrino Oscillation for Long-Baseline Experiments

The Cervera et al. formula, the best known approximate formula of neutrino oscillation probability for long-baseline experiments, can be regarded as a second-order perturbative formula with small expansion parameter epsilon \equiv Delta m^2_{21} / Delta m^2_{31} \simeq 0.03 under the assumption s_{13} \simeq epsilon. If theta_{13} is large, as suggested by a candidate nu_{e} event at T2K as well as the recent global analyses, higher order corrections of s_{13} to the formula would be needed for better accuracy. We compute the corrections systematically by formulating a perturbative framework by taking theta_{13} as s_{13} \sim \sqrt{epsilon} \simeq 0.18, which guarantees its validity in a wide range of theta_{13} below the Chooz limit. We show on general ground that the correction terms must be of order epsilon^2. Yet, they nicely fill the mismatch between the approximate and the exact formulas at low energies and relatively long baselines. General theorems are derived which serve for better understanding of delta-dependence of the oscillation probability. Some interesting implications of the large theta_{13} hypothesis are discussed.Comment: Fig.2 added, 23 pages. Matches to the published versio

New Strategies in Modeling Electronic Structures and Properties with Applications to Actinides

This chapter discusses contemporary quantum chemical methods and provides general insights into modern electronic structure theory with a focus on heavy-element-containing compounds. We first give a short overview of relativistic Hamiltonians that are frequently applied to account for relativistic effects. Then, we scrutinize various quantum chemistry methods that approximate the $N$-electron wave function. In this respect, we will review the most popular single- and multi-reference approaches that have been developed to model the multi-reference nature of heavy element compounds and their ground- and excited-state electronic structures. Specifically, we introduce various flavors of post-Hartree--Fock methods and optimization schemes like the complete active space self-consistent field method, the configuration interaction approach, the Fock-space coupled cluster model, the pair-coupled cluster doubles ansatz, also known as the antisymmetric product of 1 reference orbital geminal, and the density matrix renormalization group algorithm. Furthermore, we will illustrate how concepts of quantum information theory provide us with a qualitative understanding of complex electronic structures using the picture of interacting orbitals. While modern quantum chemistry facilitates a quantitative description of atoms and molecules as well as their properties, concepts of quantum information theory offer new strategies for a qualitative interpretation that can shed new light onto the chemistry of complex molecular compounds.Comment: 43 pages, 3 figures, Version of Recor

Modeling of a multi-link transport connection by a network of queuing systems

A model of a multi-link homogeneous transport connection with limited buffer storage in transit nodes as a network of queuing systems with discrete time is proposed. An estimate of the lower bound of the capacity of the transport connection throughput is obtained. The effect of a set of successive absolutely reliable data links located between two nondeterministic retransmission sections of a given quality on the operational characteristics of a transport connection is found

Cluster decay of Pu-236 and correlations of the probabilities of alpha decay, cluster decay, and spontaneous fission of heavy nuclei

Fifteen cases of the decay of Pu-236 accompanied by the emission of magnesium nuclei were recorded. The probability of this decay mode relative to a decay is (2.7 +/- 0.7) x 10(-14). A partial half-life of (1.25 +/- 0.12) x 10(9) yr was obtained for spontaneous fission of Pu-236. It was shown that the total probability of cluster decay and spontaneous fission for even-even nuclei with 88 less than or equal to Z less than or equal to 100 has a lower limit of approximate to 10(-9) relative to alpha decay. (C) 1995 American Institute of Physics

The use of SSNTD for the investigation of cluster radioactivity and spontaneous fission

The results of the investigation of some properties of polyethyleneterephtalate, phosphate glass and mica for the study of cluster decay and spontaneous fission of heavy nuclei are given. The investigation results of U-230 cluster decay and Ra-226 spontaneous fission investigation are presented. The probability of U-230 cluster decay in relation to alpha-decay is less than 7.5.10(14). The partial half-life of Ra-226 spontaneous fission is more than 6.6.10(17) yrs. The fusion-fission cross sections for the (Pb-208 + O-16 --> Th-224) reaction, as the inverse reaction of cluster decay, in the subbarrier region of ion energy was measured. For the energies of 78, 75, 73 and 68 MeV O-16 (lab.system) the cross-sections are 7.8; 3.7.10(-2) 8.5.10(-4) and 6.10(-6) mb, respectively