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111.
I consider some low energy restrictions for a “flipped” left-right symmetric model containing exotic fermions ofE 6 and a right-handedW-boson, all with oddR-parity. The new interactions due toW R-exchange have no significant impact on rare kaon decays, because theW R does not couple tod,s,b quarks. On the other hand,W R exchanges might induce rare processes like \(D - \bar D\) mixing, \(D^0 \to \mu \bar \mu ,D^0 \to \mu \bar e,\mu \to e\gamma ,\mu \to 3e\) , and μNeN. It turns out that the strongest bound is obtained from \(D - \bar D\) mixing. With reasonable extra assumptions, it is found that the exotic right-handed W-boson is likely to be heavier than 500 to 1500 GeV.  相似文献   
112.
The behavior of effective charges i(t) corresponding to the parameters of nonminimal coupling of scalar and gravitational fields in E6 Grand Unification Theory (GUT) in curve spacetimes is studied. It is shown that in a strong gravitational field ¦i(t)¦ grows indefinitely.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 74–11, September, 1990.  相似文献   
113.
In the present survey a method is presented for the construction of invariant tensors (with respect to a given representation) called the inclusion principle and the possibility of applying the cited method to various problems of algebra, topology, geometry, and analysis.Translated from Itogi Nauki i Tekhniki, Seriya Problemy Geometrii, Vol. 18, pp. 105–142, 1986.  相似文献   
114.
For an Ising ferromagnet with nearest-neighbour interactions of strengthK and surface magnetic fieldh, the surface free energy in the presence of a positively (or negatively) magnetized zero-field bulk phase is shown to be analytic inh for Reh<K–/, where =2.96 ... and is the inverse temperature. This puts the lower boundK–/ on the values ofh at which wetting and layering transitions can take place.  相似文献   
115.
A cold electron gas fills the lowest Landau level for high enough magnetic fields and for low enough densities. Such a situation is expected to occur for the Malmberg-O'Neil experiment and also for pulsar crusts and atmospheres. Such plasmas behave as a quasi-one-dimensional system and exhibit some peculiarities in their wave structure. We study the dispersion and damping of the low frequencies, i.e., the whistler mode, and the extraordinary mode for zero temperature. The behavior of the whistler mode depends critically on the filling number Fc=F/ , where F is the Fermi energy and is the cyclotron frequency. The one-dimensional character of the system affects the pair excitation spectrum and thus the decay of modes. We find that, in contrast to the three-dimensional situation, the plasma mode and the extraordinary mode remain undamped, while the whistler mode is undamped for all but very highk values.  相似文献   
116.
We report on a previously not observed behaviour of oscillations of the voltage over a hyperpure germanium sample, when increasing the sample current from 0.05 to 13 A, for a number of transverse magnetic fields ranging from 697 to 1746 gauss. The sample temperature was 7.54 K±0.02 K. For each magnetic field the first observed peaks in the frequency spectrum of the sample voltage go to chaos by the period-doubling route and simultaneously shift to lower frequencies (first scenario). Superimposed upon this chaotic spectrum a new peak emerges, which again shifts to lower frequencies with increasing sample current (second scenario). A complementary effect of the sample current and the magnetic field is detected for four properties: firstly, the sudden onset of high resistance in the current versus voltage diagram, secondly, the transition between the two frequency scenarios described above, thirdly the presence of certain frequencies in the sample voltage spectra and fourthly the occurrence of an amplitude maximum for the principal frequency of the first scenario. It is shown that the first two transitions are interrelated.  相似文献   
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