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31.
We propose a model in which a recently reported modulation in the decay of the hydrogenlike ions 140Pr58+, 142Pm60+ and 122I52+ arises from the coupling of rotation to the spin of electron and nucleus. The model shows that the spin–spin coupling of electron and nucleus does not contribute to the modulation and predicts that the anomaly cannot be observed if the motion of the ions is rectilinear, or if the ions are stopped in a target. It also supports the notion that the modulation frequency is proportional to the inverse of the atomic mass and that no modulation is expected for the β+-decay. The model predicts that for He-like ions the modulation is still present. 相似文献
32.
The covariant Dirac equation and its solutions show that rotation and acceleration can be used to generate and control spin currents. 相似文献
33.
Giorgio Papini 《General Relativity and Gravitation》2008,40(6):1117-1144
External gravitational fields induce phase factors in the wave functions of particles. The phases are exact to first order
in the background gravitational field, are manifestly covariant and gauge invariant and provide a useful tool for the study
of spin–gravity coupling and of the optics of particles in gravitational or inertial fields. We discuss the role that spin–gravity
coupling plays in particular problems. 相似文献
34.
The leading asymptotic term for the function that counts theeigenvalues of the Stokes operator is determined for fairlygeneral underlying bounded domains. Moreover, the remainderis estimated in terms of the fractality of the boundary of thedomain. The results obtained resemble corresponding ones forthe Dirichlet Laplacian. 1991 Mathematics Subject Classification:35P20. 相似文献
35.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
36.
The variation of the spectral properties of semi-transparent (polystyrene: PS), transparent (potassium bromide: KBr) and opacified particles (silver coated silica spheres: Ag-SiO2) is presented from 0.25 to 20 μm. The spectral properties of binary mixtures PS/KBr and PS/Ag-SiO2 are also studied. The sensitivity of the spectral properties to the particle diameters causes the near-normal hemispherical spectral reflectance R to decrease when the particle size increases from 10 to 1800 μm. The addition of KBr transparent particles to PS powders results in an increase in the reflectance values of the mixtures in the near and mid-infrared wavelength range. Furthermore, the effect of the addition of opacified reflecting particles depends on the wavelength region and on the PS content ([PS]). For < < 1.64 μm, R decreases when [PS] decreases from 1 to 0.56 and then R increases for [PS] values decreasing from 0.56 to 0. For < > 1.64 μm, R decreases when PS content increases from 0 to 1. 相似文献
37.
S. A. Koldobskiy O. Adriani G. A. Bazilevskaya G. C. Barbarino R. Bellotti E. A. Bogomolov M. Boezio V. Bonvicini M. Bongi S. Bottai A. Bruno A. Vacchi E. Vannuccini G. I. Vasilyev S. A. Voronov A. M. Galper C. De Santis V. Di Felice G. Zampa N. Zampa M. Casolino D. Campana A. V. Karelin P. Carlson G. Castellini F. Cafagna A. A. Kvashnin A. N. Kvashnin S. V. Koldashov S. Y. Krutkov A. A. Leonov A. G. Mayorov V. V. Malakhov M. Martucci L. Marcelli W. Menn M. Merge V. V. Mikhailov E. Mocchiutti A. Monaco N. Mori R. Munini G. Osteria B. Panico P. Papini P. Picozza M. Pearce M. Ricci S. B. Ricciarini M. F. Runtso M. Simon R. Sparvoli P. Spillantini Y. I. Stozhkov Y. T. Yurkin 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(2):151-153
The preliminary results from measurements of deuteron fluxes in galactic cosmic rays (GCR) in the vicinity of the Earth in 2006–2009 are presented. The results are obtained by analyzing data from the PAMELA experiment aboard the Resurs DK-1 satellite. High-precision detection instruments provided an opportunity to identify GCR deuterons and measure their spectrum in the energy interval of 90–650MeV/nucleon. Spectra averaged over six-month intervals from the summer of 2006 to the summer of 2009 (the solar activity minimum) are presented. The influence of solar modulation on the observed spectrum is clearly seen in the results. 相似文献
38.
V. V. Mikhailov O. Adriani G. A. Bazilevskaya G. C. Barbarino R. Bellotti E. A. Bogomolov M. Boezio V. Bonvicini M. Bongi S. Bottai A. Bruno A. Vacchi E. Vannuccini G. I. Vasilyev S. A. Voronov A. M. Galper C. De Santis V. Di Felice G. Zampa N. Zampa M. Casolino D. Campana A. V. Karelin P. Carlson G. Castellini F. Cafagna A. A. Kvashnin A. N. Kvashnin S. V. Koldashov S. A. Koldobskiy S. Y. Krutkov A. A. Leonov A. G. Mayorov V. V. Malakhov M. Martucci L. Marcelli W. Menn M. Merge Yu. V. Mikhailova E. Mocchiutti A. Monaco N. Mori R. Munini G. Osteria B. Panico P. Papini P. Picozza M. Pearce M. Ricci S. B. Ricciarini M. F. Runtso M. Simon R. Sparvoli P. Spillantini Y. I. Stozhkov Y. T. Yurkin 《Physics of Atomic Nuclei》2018,81(4):515-519
Measurements of secondary-electron and secondary-positron fluxes below the geomagnetic cutoff in near-Earth space were performed by means of the PAMELA magnetic spectrometer installed on board the Resurs-DK1 satellite launched on June 15, 2006, in an elliptical orbit of inclination 70° and altitude 350 to 600 km. This spectrometer permits measuring the fluxes of electrons and positrons over a wide energy range, as well as determining their spatial distributions to a precision of about 2°. A calculation of particle trajectories in the geomagnetic field makes it possible to separate electrons and positrons originating from cosmic-ray interactions in the Earth’s magnetosphere. The spatial distributions of quasitrapped, trapped, and short-lived albedo positrons and electrons of energy above 70 MeV in the radiation belt were analyzed. The ratio of the electron-to-positron fluxes and the energy spectra of the electrons and positrons in question are indicative of different productionmechanisms for stably trapped and quasitrapped secondary particles. 相似文献
39.
Jesús M.F. Castillo Manuel González Pier Luigi Papini 《Nonlinear Analysis: Theory, Methods & Applications》2012
We study the stability properties of the class of weak*-extensible spaces introduced by Wang, Zhao, and Qiang showing, among other things, that weak*-extensibility is equivalent to having a weak*-sequentially continuous dual ball (in short, w*SC) for duals of separable spaces or twisted sums of w*SC spaces. This shows that weak*-extensibility is not a 3-space property, solving a question posed by Wang, Zhao, and Qiang. We also introduce a restricted form of weak*-extensibility, called separable weak*-extensibility, and show that separably weak*-extensible Banach spaces have the Gelfand–Phillips property, although they are not necessarily w*SC spaces. 相似文献
40.