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61.
The vacuum uv emission of the 15N22+ ion has been recorded for the first time. Rotational analysis of two bands, analogous to those already observed in the case of the natural isotope, confirm their assignment to the D1Σu+-X1Σg+ (0, 0) and (1, 1) bands. More precise data are also obtained for the 3Σg? state which perturbs ground state vibrational levels. 相似文献
62.
Pierre Boissel Gérard Hauchecorne François Kerherve Guy Mayer 《Optics Communications》1976,19(1):125-128
We have studied the evolution of the light transmitted through matter in which an optical breakdown is taking place. With a two-waves interferometer made a birefringent plate between polarizers we get informations about the time correlation function of the fields. With an interferometer made of two identical harmonic generating plates separated by a dispersion medium, we learn about the correlation function of the square of the fields. Both systems act as spectral filters with a notch cosine-shaped centered at the incident frequency. We have also observed a transient angular spreading of the beam not previously emphasized which brings a further complication in the picture. 相似文献
63.
C.E.T. Gonçalves da Silva 《Solid State Communications》1979,30(5):283-287
The magnetic properties of an intermediate valence compound are discussed within a single-ion framework. The effects of configuration mixing, crystalline electric fields, and external magnetic fields are included in the hamiltonian. The method incorporates in one single consistent approach both coherent (quantum) and incoherent (thermal) fluctuations. Numerical evaluation of the susceptibility and field dependent magnetization with parameters appropriate for TmSe yields results in good agreement with experiment. 相似文献
64.
François Bayen 《Letters in Mathematical Physics》1979,3(3):161-167
The domain of convergence of the Zassenhaus formula in a Banach algebra is studied. This domain is shown to be strictly larger than the one which was already known. 相似文献
65.
J. Blachot J. Crançon B. de Goncourt A. Gizon A. Llères 《Zeitschrift für Physik A Hadrons and Nuclei》1985,321(4):645-651
Cross sections, recoil energy distributions for residues produced by14N,20Ne,40Ar on124Sn targets have been measured in the 10–70 MeV/u intermediate energy range. As the projectile energy increases, processes as complete fusion-evaporation, incomplete fusion-evaporation and intranuclear cascade-evaporation participate progressively in the nuclear collisions. Peculiar residues corresponding to a gain of 4, 5 or even 6 protons for the124Sn target have been observed in the 30–50 MeV energy range. 相似文献
66.
This research deals with the ultrasonic characterization of thermal damage in concrete. This damage leads to the appearance of microcracks which then evolve in terms of volume rate and size in the material. The scattering of ultrasonic waves from the inclusions is present in this type of medium. The propagation of the longitudinal wave in the heterogeneous media is studied via a homogenization model that integrates the multiple scattering of waves. The model allows us to determine the phase velocity and the attenuation according to the elements which make the medium. Simulations adapted to the concrete are developed in order to test the responses of the model. These behaviors are validated by an experimental study: the measurements of phase velocity and attenuation are performed in immersion, with a comparison method, on a frequency domain which ranges from 160 kHz to 1.3 MHz. The analysis of different theoretical and experimental results obtained on cement-based media leads to the model validation, on the phase velocity behavior, in the case of a damage simulated by expanded polystyrene spheres in granular media. The application to the case of a thermally damaged concrete shows a good qualitative agreement for the changes in velocity and attenuation. 相似文献
67.
A. G. Popeko A. V. Belozerov Ch. Briançon V. I. Chepigin O. Dorvaux K. Hauschild A. P. Kabachenko A. Korichi A. Lopez-Martens O. N. Malyshev Yu. Ts. Oganessian Š. Šáro A. V. Shutov A. I. Svirikhin A. V. Yeremin 《Physics of Atomic Nuclei》2006,69(7):1183-1187
The JINR (Dubna)-IN2P3 (France) Collaboration project aimed at the α, β γ, spectroscopy of the transfermium element isotopes using heavy-ion beams of the U-400 cyclotron and the modernized recoil
separator VASSILISSA was launched at Dubna. During the first full-scale experiment in September–October 2004, nobelium and
lawrencium isotopes produced in the 48Ca + 207,208Pb → 255,256No* and 48Ca + 209Bi → 257Lr* reactions were studied.
The text was submitted by the authors in English. 相似文献
68.
I. Štekl P. Čermák P. Beneš V. B. Brudanin K. N. Gusev V. G. Egorov A. A. Klimenko V. E. Kovalenko A. Kovalík N. I. Rukhadze A. V. Salamatin V. V. Timkin Ts. Vylov Ch. Briançon F. Šimkovic 《Czechoslovak Journal of Physics》2006,56(5):505-510
Present status of the experiment TGV II which is devoted to the measurement of double-beta decay of 106Cd is given. The low background spectrometer TGV II is installed in the Modane Underground Laboratory and has been running
from February 2005 with approx 10 grams of 106Cd enriched at 75%. After an analysis of 3736 hours of experimental data the new improved half-life limit for 2νEC/EC decay of 106Cd (0
g.s.
+
→ 0
g.s.
+
) is given as T
1
2/2ν
> 4.8 × 1019 years (90% CL). The search for 2νEC/EC decay of 106Cd to the excited states of 106Pd allows to determine the limits of the half-lives T
1
2/2ν
(0
g.s.
+
→ 2
1
+
) > 3.9 × 1019 years (90% CL) and T
1
2/2ν
(0
g.s.
+
→ 0
1
+
) > 5.8 × 1019 years (90% CL).
Presented by I. Štekl at the Workshop on calculation of double-beta-decay matrix elements (MEDEX’05), Corfu, Greece, September
26–29, 2005. 相似文献
69.
We propose a numerical method to accurately discriminate the influence of the different intrachannel nonlinear effects occurring in 40 Gbit/s optical transmissions, following an analogy with methods used to discriminate WDM interchannel effects. In contrast to other studies showing the predominance of intrachannel cross-phase modulation when low-dispersion fibers are used, in our study intrachannel four-wave mixing is the most penalizing effect in all investigated cases. 相似文献
70.