b --> s g g decay in the two and three Higgs doublet models with CP violating effects

We study the decay width and CP-asymmetry of the inclusive process b--> s g g (g denotes gluon) in the three and two Higgs doublet models with complex Yukawa couplings. We analyse the dependencies of the differential decay width and CP-asymmetry to the s- quark energy E_s and CP violating parameter \theta. We observe that there exist a considerable enhancement in the decay width and CP asymmetry is at the order of 10^{-2}. Further, it is possible to predict the sign of C_7^{eff} using the CP asymmetry.Comment: 15 pages, 7 Figures (required epsf style

On The Expected Photon Spectrum in B -> X_s + gamma and Its Uses

Measuring the photon energy spectrum in radiative B decays provides essential help for gaining theoretical control over semileptonic B transitions. The hadronic recoil mass distribution in B -> X_u \ell\nu promises the best environment for determining |V_ub|. The theoretical uncertainties are largest in the domain of low values of the lepton pair mass q^2. Universality relations allow to describe this domain reliably in terms of the photon spectrum in B -> X_s + \gamma. A method is proposed to incorporate 1/m_b corrections into this relation. The low-E_\gamma tail in radiative decays is important in the context of extracting |V_ub|. We argue that CLEO's recent fit to the spectrum underestimates the fraction of the photon spectrum below 2 GeV. Potentially significant uncertainties enter in the theoretical evaluation of the integrated end-point lepton spectrum or the B -> X_u \ell\nu width with a too high value of the lower cut on q^2 in alternative approaches to |V_ub|.Comment: 24 pages, 6 figures, LaTeX. Revised: Complete version. Numerical predictions are improved and the estimate for the decay fraction revised. The theoretical expectations for the decay fraction and the spectrum itself are given on the plot

Оценка зависимости пассажирооборота от макроэкономических факторов

[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT The instability of the domestic transport services market, significant fluctuations in demand on the part of the population, make it necessary to evaluate the range of problems under study with particular attention. The author analyzes the impact of macroeconomic factors on passenger traffic. The article reveals the high dependence of the total passenger flow on the economic condition of the country, the population’s solvency margin. The change in the strength of the connection between passenger turnover and GDP over the last 24 years is considered. It is suggested that there is some «inertia» of transportation indicators and, at the same time, the predominant coincidence of the dynamics of the gross domestic product and the total passenger flow is analytically proved. Keywords: transport, macroeconomic factors, passenger transportation, forecasting, GDP, passenger turnover, interdependence of indicators.Текст аннотации на англ. языке и полный текст статьи на англ. языке находится в прилагаемом файле ПДФ (англ. версия следует после русской версии).Нестабильность отечественного рынка транспортных услуг, существенные колебания спроса со стороны населения заставляют с особым вниманием оценивать круг исследуемых проблем. Автором проводится анализ влияния макроэкономических факторов на показатели пассажирских перевозок. Показывается высокая зависимость суммарного пассажиропотока от экономического состояния страны, уровня платежеспособности населения. Рассматривается изменение силы связи между пассажирооборотом и ВВП за последние 24 года. Выдвигается предположение о некоторой «инерционности» показателей перевозок и вместе с тем аналитически доказывается преимущественное совпадение динамики валового внутреннего продукта и суммарного пассажиропотока

Existence of two-channel Kondo regime for tunneling impurities with resonant scattering

Dynamical tunneling systems have been proposed earlier to display a two-channel Kondo effect, the orbital index of the particle playing the role of a pseudospin in the equivalent Kondo problem, and the spin being a silent channel index. However, as shown recently by Aleiner et al. [Phys. Rev. Lett. 86, 2629 (2001)], the predicted two-channel Kondo behavior can never be observed in the weak coupling regime, where the tunneling induced splitting of the levels of the tunneling system always dominates the physics. Here we show that the above scenario changes completely if the conduction electrons are scattered by resonant scattering off the tunneling impurity; Then - as a non-perturbative analysis reveals - the two-channel Kondo regime can easily be reached.Comment: 10 PRB page

On the Occurrence of Finite-Time-Singularities in Epidemic Models of Rupture, Earthquakes and Starquakes

We present a new kind of critical stochastic finite-time-singularity, relying on the interplay between long-memory and extreme fluctuations. We illustrate it on the well-established epidemic-type aftershock (ETAS) model for aftershocks, based solely on the most solidly documented stylized facts of seismicity (clustering in space and in time and power law Gutenberg-Richter distribution of earthquake energies). This theory accounts for the main observations (power law acceleration and discrete scale invariant structure) of critical rupture of heterogeneous materials, of the largest sequence of starquakes ever attributed to a neutron star as well as of earthquake sequences.Comment: Revtex document of 4 pages including 1 eps figur

Dynamics of two interacting Bose-Einstein condensates

We analize the dynamics of two trapped interacting Bose-Einstein condensates and indentify two regimes for the evolution: the regime of slow periodic oscillations and the regime of strong non-linear mixing leading to the damping of the relative motion of the condensates. We compare our predictions with an experiment recently performed at JILA.Comment: 4 pages RevTeX, 3 eps figure

Unified Scaling Law for Earthquakes

We show that the distribution of waiting times between earthquakes occurring in California obeys a simple unified scaling law valid from tens of seconds to tens of years, see Eq. (1) and Fig. 4. The short time clustering, commonly referred to as aftershocks, is nothing but the short time limit of the general hierarchical properties of earthquakes. There is no unique operational way of distinguishing between main shocks and aftershocks. In the unified law, the Gutenberg-Richter b-value, the exponent -1 of the Omori law for aftershocks, and the fractal dimension d_f of earthquakes appear as critical indices.Comment: 4 pages, 4 figure

BCS pairing in a trapped dipolar Fermi gase

We present a detailed study of the BCS pairing transition in a trapped polarized dipolar Fermi gas. In the case of a shallow nearly spherical trap, we find the decrease of the transition temperature as a function of the trap aspect ratio and predict the existence of the optimal trap geometry. The latter corresponds to the highest critical temperature of the BCS transition for a given number of particles. We also derive the phase diagram for an ultracold trapped dipolar Fermi gases in the situation, where the trap frequencies can be of the order of the critical temperature of the BCS transition in the homogeneous case, and find the critical value of the dipole-dipole interaction energy, below which the BCS transition ceases to exist. The critical dipole strength is obtained as a function of the trap aspect ratio. Alternatively, for a given dipole strength there is a critical value of the trap anisotropy for the BCS state to appear. The order parameter calculated at criticality, exhibits nover non-monotonic behavior resulted from the combined effect of the confining potential and anisotropic character of the interparticle dipole-dipole interation.Comment: 14 pages, 3 figure

Three-body recombination of ultra-cold atoms to a weakly bound ss level

We discuss three-body recombination of ultra-cold atoms to a weakly bound $s$ level. In this case, characterized by large and positive scattering length $a$ for pair interaction, we find a repulsive effective potential for three-body collisions, which strongly reduces the recombination probability and makes simple Jastrow-like approaches absolutely inadequate. In the zero temperature limit we obtain a universal relation, independent of the detailed shape of the interaction potential, for the (event) rate constant of three-body recombination: $\alpha_{\rm rec}=3.9\hbar a^4/m$, where $m$ is the atom mass.Comment: 10 pages, 3 Postscript figure