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2.
The neutron deficient nucleus94Pd was identified and studied for the first time by in-beam spectroscopy. An I=(14+) isomer with t1/2=0.8 (2) s was observed in a recoil catcher setup inside the multi-detector -array OSIRIS. Filter detectors for neutrons and charged particles were used to identify the (2p2n) exit channel of the reaction58Ni+40Ca, populated with only 0.06% of the total evaporation residue cross section. The structure of the isomer is discussed within the frame work of shell model calculations in the (p1/2,g9/2) model space with emphasis on the g 9 2/2 T=0, I=1,9 pairing two-body matrix elements.Communicated by: D. Schwalm  相似文献   
3.
Then th,α)-reaction spectroscopical data are reported on95Mo,123Te and145Nd (target nuclei). The95Mo(n, α)92Zr and123Te(n, α)120Sn reactions showed up two lines each corresponding to the ground state and the 1st excited state with a total cross section of 32 ub and 52 μb respectively. In the case of145Nd(n, α)142Ce, a transition only to the 1st excited state of142Ce is present. It is shown that in the case of95Mo,145Nd and probably123Te, most of the cross-section comes respectively from the 2+ possibly 4?, and 0 bound levels whose widths are determined to beΓ α=0.5 × 10?6 eV,Γ α=1.6×10?8 eV andΓ α=1.6 × 10?6 eV. The present results on these three nuclei, when combined with the existing data, are consistent with the calculated statistical model values.  相似文献   
4.
Average lifetimes of unresolved transitions deexciting very high spin states populated in28Si(136, 129Xe,xn)164? x, 157?xEr reactions have been determined by a Doppler shift attenuation method. We find that the yrast bump region between 1.0 and 1.6 MeV contains a majority of strongly collectiveE2 transitions with very short lifetimes (a few tens of fsec) in the well deformed nuclei around159Er and, with less certainty, almost comparably short lifetimes in the more spherical nuclei around152Er. In the high energy region of 2.0–3.2 MeV we observe transitions which depopulate longer lived states in the nuclei nearN=82 than in the well deformed systems.  相似文献   
5.
Conversion coefficients and conversion ratios of someγ-transitions in201Tl and203Tl were measured by means of simultaneous spectroscopy ofγ-quanta and conversion electrons employing intensity calibrated semiconductor detectors. The experiments aimed at a precision as high as possible within the limits of the experimental methode used. Theγ-transitions were of the typeM 1(+E2). From the measured values the penetration parameters of the internal conversion for theM 1 components (λ) together with the multipol mixing ratios (δ2) were deduced. The necessary theoretical coefficients were taken from the tables of Hager and Seltzer. The results are for the ?-forbidden 331 keV transition in201Tl,λ=+4.0±1.0,δ 2=1.78±0.16; for the ?-allowed 361 keV transition in201Tl,λ=+0.5±0.5,δ 2=0.02±0.02; for the ?-forbidden 279 keV transition in203Tl,λ=+ 5.71±0.45,δ 2=1.55±0.08.  相似文献   
6.
The branching ratio for the transition from the 0.90 MeV second excited to the 0.57 MeV first excited state in 207Pb has been measured to be (0.59 ± 0.09)%. The corresponding B(M1) exceeds recent theoretical predictions.  相似文献   
7.
The Coxeter–Weyl groups W(A4), W(B4), and W(D4) have proven very useful for two-qubit systems in quantum information theory. A simple technique is employed to construct the unitary matrix representations of the groups, based on quaternionic transformation of the usual reflection matrices. The von Neumann entropy of each reduced density matrix is calculated. It is shown that these unitary matrix representations are naturally related to various universal quantum gates and they lead to entangled states. Canonical decomposition of generators in terms of fundamental gate representations is given to construct the quantum circuits.  相似文献   
8.
A highly bright white organic light-emitting diode (OLED) was realized by using a highly bright blue emitting layer, 1,7-diphenyl-4-biphenyl-3,5-dimethyl-l,7-dihydrodipyrazolo[3,4-b;4',3'-e]pyridine (PAP-Ph), together with a 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM)-doped Alq [tris(8-hydroxyquinolinato) aluminum (Ⅲ)] layer to provide the blue, red and green emission for color mixing. With appropriate thickness control, the white-light OLED has a performance that reaches 24700 cd/m2 at 15 V, 1.93 lm/W at 6.5 V, and >300 cd/m2 at 7.7 mA/em2. The Commission Internationale de l'Eclairage (CIE) coordinates of the emitted light vary in a very small range, from (0.35, 0.34) to (0.34, 0.35), when forward voltages change from 6 to 12 V.  相似文献   
9.
High-spin properties of129Cs have been investigated following116Cd(18O, p4nγ) and122Sn(11B, 4nγ) reactions. Rotational bands built on h11/2,g7/2, and d5/2 singleproton states were observed. At higher spins, band-crossings attributed to the alignment of h11/2 neutrons were observed. A comparison with total Routhian cranking calculations support this interpretation.  相似文献   
10.
The 115In nucleus was studied by means of γ-ray spectroscopic measurements. This nucleus was populated with the 100Mo(18O, p2n)115In reaction and a charged-particle detector array was used to identify the proton evaporation channel. A level scheme with 17 new transitions is presented and compared with theoretical predictions based on the particle + core model.  相似文献   
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