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The results of the photometric observations of comet 29P/Schwassmann-Wachmann 1 are analyzed. The comet demonstrates substantial activity at heliocentric distances larger than 5 AU, outside the water ice sublimation zone. The CCD images of the comet were obtained in wideband R filters at the 6m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) and at the 2m telescope of the Peak Terskol Observatory. The processing of the images with special digital filters allowed the active structures (jets) to be distinguished in the dust coma of the comet. With the cross correlation method, the rotation period of the cometary nucleus was determined as 12.1 and 11.7 days for the observations taken in December 2008, and February 2009, respectively. The probable causes of the difference in the estimates of the rotation period of the cometary nucleus obtained by differen authors are discussed., Comment: 7 pages, 5 figures

Tunneling of spinless electrons from a single-channel emitter into an empty collector through an interacting resonant level of the quantum dot (QD) is studied, when all Coulomb screening of charge variations on the dot is realized by the emitter channel and the system is mapped onto an exactly solvable model of a dissipative qubit. In this model we describe the qubit density matrix evolution with a generalized Lindblad equation, which permit us to count the tunneling electrons and therefore relate the qubit dynamics to the charge transfer statistics. In particular, the coefficients of its generating function equal to the time dependent probabilities to have the fixed number of electrons tunneled into the collector are expressed through the parameters of a non-Hermitian Hamiltonian evolution of the qubit pure states in between the successive electron tunnelings. From the long time asymptotics of the generating function we calculate Fano factors of the second and third order (skewness) and establish their relation to the extra average and cumulant, respectively, of the charge accumulated in the transient process of the empty QD evolution beyond their linear time dependence. It explains the origin of the sub and super Poisson shot noise in this system and shows that the super Poisson signals existence of a non-monotonous oscillating transient current and the qubit coherent dynamics. The mechanism is illustrated with particular examples of the generating functions, one of which coincides in the large time limit with the $1/3$ fractional Poissonian realized without the real fractional charge tunneling., Comment: 13 pages, 6 figures

We consider tunneling of spinless electrons from a single channel emitter into an empty collector through an interacting resonant level of the quantum dot (QD). When all Coulomb screening of sudden charge variations of the dot during the tunneling is realized by the emitter channel, the system is mapped onto an exactly solvable model of a dissipative qubit. The qubit density matrix evolution is described with a generalized Bloch equation which permits us to count the tunneling electrons and find the charge transfer statistics. The two generating functions of the counting statistics of the charge transferred during the QD evolutions form its stationary and empty state have been expressed through each other. It is used to calculate the spectrum of the steady current noise and demonstrate occurrence of the bifurcation of its single zero-frequency minimum into two finite-frequency dips due to the qubit coherent dynamics., Comment: 6 pages 3 figures. arXiv admin note: text overlap with arXiv:1704.01226, arXiv:1512.06463

We consider tunneling of spinless electrons from a single-channel emitter into an empty collector through an interacting resonant level of the quantum dot. When all Coulomb screening of sudden charge variations of the dot during the tunneling is realized by the emitter channel, the system is described with an exactly solvable model of a dissipative qubit. To study manifestations of the coherent qubit dynamics in the collector $\it{a.c.}$ response we derive solution to the corresponding Bloch equation for the model quantum evolution in the presence of the oscillating voltage of frequency $% \omega$ and calculate perturbatively the $\it{a.c.}$ response in the voltage amplitude. We have shown that in a wide range of the model parameters the coherent qubit dynamics results in the non-zero frequencies resonances in the amplitudes dependence of the $\it{a.c.}$ harmonics and in the jumps of the harmonics phase shifts across the resonances. In the first order the $\it{a.c.}$ response is directly related to the spectral decomposition of the corresponding transient current and contains only the first $\omega$ harmonic, whose amplitude exhibits resonance at $\omega =\omega_I $, where $\omega_I$ is the qubit oscillation frequency. In the second order we have obtained the $2 \omega$ harmonic of the $\it{a.c.}$ response with resonances in the frequency dependence of its amplitude at $\omega_I$, $\omega_I/2$ and zero frequency and also have found the frequency dependent shift of the average steady current., Comment: 8 pages, 4 figs. arXiv admin note: substantial text overlap with arXiv:1512.06463

We consider tunneling of spinless electrons from a single channel emitter into an empty collector through an interacting resonant level of the quantum dot. When all Coulomb screening of sudden charge variations of the dot during the tunneling is realized by the emitter channel, the system is described with an exactly solvable model of a dissipative qubit. We derive the correspondent Bloch equation for its quantum evolution. We further use it to specify the qubit transient dynamics towards its stationary quantum state after sudden change of the level position. We demonstrate that the time-dependent tunneling current characterizing this dynamics exhibits an oscillating behavior for a wide range of the model parameters., Comment: final version published in EPL with minor corrections of the language, added reference, 5 pages, 2 figs

We consider an adiabatic Landau-Zener model of two-level system diagonally coupled to an Ohmic bosonic bath of large spectral width and derive through fermionization its exact solution at a special value of the coupling constant. From this solution we obtain the characteristic function of the distribution of energy transferred to the bath during the evolution of the system ground state as a functional determinant of a single particle operator. At zero temperature this distribution is further found to be exponential and at finite temperature the first three moments of the distribution are calculated., Comment: 4 pages, no figures, to appear in PRB

Influence of the meteoroid bombardment on properties of the lunar exosphere has been confirmed. Quick increase in the zenith column density of Na atoms above the lunar north pole on August 13, 2009 at 0-1 UT is detected and explained by numerous collisions of relatively small Perseid meteoroids (< 1 kg) with the Moon during maximum of the Perseid meteor shower. New stringent upper limits of the column densities for Ca, Ba, and Ti atoms in the lunar exosphere are obtained as 5*10^7, 2.2*10^6, and 6.9*10^8 cm^-2, respectively. It is found that the content of impact-produced Ca and Al atoms in the lunar exosphere is depleted as compared to that of Na atoms., Comment: 11 pages, 4 figures, 3 tables; accepted in Planetary and Space Science

We study low energy spin and charge transport through a 1D Mott-Hubbard insulator of finite length $L$ attached to Fermi liquid reservoirs characterized by different chemical potentials for electrons of opposite spin polarizations as it happens in quantum spin Hall insulators. We calculate the average currents (charge and spin) and their correlators and demonstrate how a transition induced by the reservoirs to the low energy Fermi liquid regime results in breakdown of the spin-charge separation, which is visible in the presence of the spin dependent voltages and a weak one electron scattering in the system. These calculations are carried out under assumption that the Hubbard gap 2M is large enough: $M > T_L \equiv v_c/L$ ($v_c$: charge velocity in the wire) and the scattering rate $\Gamma_s \ll T_L$. Relation of these results to Kondo dot transport in the Toulouse limit is also clarified., Comment: 5 two-column pages, no figures

We have studied the zero-temperature statistics of the charge transfer between the two edges of Quantum Hall liquids of, in general, different filling factors, $\nu_{0,1}=1/(2 m_{0,1}+1)$, with $m_0 \geq m_1\geq 0$, forming Mach-Zehnder interferometer. General expression for the cumulant generating function in the large-time limit is obtained for symmetric interferometer with equal propagation times along the two edges between the contacts and constant bias voltage. The low-voltage limit of the generating function can be interpreted in terms of the regular Poisson process of electron tunneling, while its leading large-voltage asymptotics is proven to coincide with the solution of kinetic equation describing quasiparticle transitions between the $m$ states of the interferometer with different effective flux through it, where $m\equiv 1+m_{0}+m_{1}$. For $m>1$, this dynamics reflects both the fractional charge $e/m$ and the fractional statistical angle $\pi /m$ of the tunneling quasiparticles. Explicit expressions for the second (shot noise) and third cumulants are obtained, and their voltage dependence is analyzed., Comment: 11 two-column pages, 4 figures

Traditional models of macroeconomic dynamics are fundamentally incorrect. The reason lies in a misunderstanding of peculiarities of the analysis of infinitesimal quantities. However, even those types of solutions that are envisaged by the above-mentioned models are nonrepresentative in the sense of the reflection of realities. It became obvious that the techniques of the theory of linear differential equations were insufficient here. Accordingly, the scientists' attention switched to the theory of nonlinear differential equations. At the same time, balance and, accordingly, the model with matrix properties are objectively inherent in the economic system. For the reduction of this model to a differential form, there exist rather elementary means that proved to be unclaimed. Macroeconomic rhetoric - the power of the accelerator, a lag on the part of demand, etc. - accompanied by the use of a lot of abstract coefficients prevailed. However, there is no organic interrelation between matrix and nonlinear differential equations. On the contrary, it can be said that linear theory of integral equations originated in matrix analysis. The Fredholm linear integral equation of the second kind with a parameter-dependent kernel proves to be rather representative with regard to the class of possible solutions. It seems that it can be used for the description of any zigzags of the economy. The price one has to pay for this is the nontriviality of existing theory., Comment: 36 pages; made minor textual corrections

We have developed a theory of quasiparticle backscattering in a system of point contacts formed between single-mode edges of several Fractional Quantum Hall Liquids (FQHLs) with in general different filling factors $\nu_j$ and one common single-mode edge $\nu_0$ of another FQHL. In the strong-tunneling limit, the model of quasiparticle backscattering is obtained by the duality transformation of the electron tunneling model. The new physics introduced by the multi-point-contact geometry of the system is coherent splitting of backscattered quasiparticles at the point contacts in the course of propagation along the common edge $\nu_0$. The ``branching ratios'' characterizing the splitting determine the charge and exchange statistics of the edge quasiparticles that can be different from those of Laughlin's quasiparticles in the bulk of FQHLs. Accounting for the edge statistics is essential for the system of more than one point contact and requires the proper description of the flux attachement to tunneling electrons., Comment: 12 pages, 2 figures

We suggest an approach to constructing physical systems with dynamical characteristics of the complex analytic iterative maps. The idea follows from a simple notion that the complex quadratic map by a variable change may be transformed into a set of two identical real one-dimensional quadratic maps with a particular coupling. Hence, dynamical behavior of similar nature may occur in coupled dissipative nonlinear systems, which relate to the Feigenbaum universality class. To substantiate the feasibility of this concept, we consider an electronic system, which exhibits dynamical phenomena intrinsic to complex analytic maps. Experimental results are presented, providing the Mandelbrot set in the parameter plane of this physical system., Comment: 9 pages, 3 figures