[en] We obtain uncertainty and certainty relations of state-independent form for the three Pauli observables with use of the Rényi entropies of order α ∈ (0; 1]. It is shown that these entropic bounds are tight in the sense that they are always reached with certain pure states. A new result is the condition for equality in Rényi-entropy uncertainty relations for the Pauli observables. Upper entropic bounds in the pure-state case are also novel. Combining the presented bounds leads to a band, in which the rescaled average Rényi α-entropy ranges for a pure measured state. A width of this band is compared with the Tsallis formulation derived previously. (general)

[en] The doubly excited ^1,3D⁰ resonance states of Ps^- associated with N=3, N=4 and N=5 Ps thresholds have been investigated using highly accurate correlated wave functions with exponents generated by a quasi-random process. Resonance parameters (both resonance positions and widths) are extracted in the framework of the stabilization method and the complex coordinate rotation method. In addition to many Feshbach resonances below the various Ps thresholds, we have identified two ¹D⁰ shape resonances with one each lying above the N=3 and N=4 thresholds, respectively, and two ³D⁰ shape resonances with one each lying above the N=3 and N=5 thresholds, respectively. The 1^D0 shape resonance associated with N=3 Ps threshold and some other Feshbach resonances are reported for the first time in the literature. (authors)

No abstract available

[en] The ⁹Be(⁷Li,α)¹²B reaction has been studied at E (⁷Li) =20 MeV using a multiangle spectrograph. Thirty-seven states of ¹²B with E/subx/ < 14 MeV have been observed. Angular distributions are presented for the first seven states of ¹²B. The neutron reduced widths extracted from experimental total widths of the positive parity states are compared with shell-model predictions

No abstract available

[en] A laser system with a narrow generation line for secondary laser cooling of ⁸⁷Sr atoms has been developed and investigated. It is planned to use ultracold ⁸⁷Sr atoms loaded in an optical lattice in an optical frequency standard. To this end, a 689-nm semiconductor laser has been stabilised using an external reference ultrastable cavity with vibrational and temperature compensation near the critical point. The lasing spectral width was 80 Hz (averaging time 40 ms), and the frequency drift was at a level of 0.3 Hz s^-1. Comparison of two independent laser systems yielded a minimum Allan deviation: 2 × 10^-14 for 300-s averaging. It is shown that this system satisfies all requirements necessary for secondary cooling of 87Sr atoms using the spectrally narrow ¹S₀ — ³P₁ transition (λ = 689 nm). (cooling of atoms)

No abstract available

[en] We analyze the fluctuation properties of nuclear energy levels and widths with new spectrally averaged measures. A remarkably close agreement between the predictions of random-matrix theories and experiment is found

No abstract available

[en] Transmission and capture data from ⁵⁸Ni were analyzed up to 120 keV and are reported. High-resolution scattering measurements for Fe are discussed, and the determination of the J/sup π/ value for most resonances seen in transmission data up to 400 keV is given, including an attempt at evaluation of the resonances of ⁵⁶Fe on the basis of recently published data. 4 figures, 3 tables