216 research outputs found

    Transfer ionization and its sensitivity to the ground-state wave function

    Full text link
    We present kinematically complete theoretical calculations and experiments for transfer ionization in H++^++He collisions at 630 keV/u. Experiment and theory are compared on the most detailed level of fully differential cross sections in the momentum space. This allows us to unambiguously identify contributions from the shake-off and two-step-2 mechanisms of the reaction. It is shown that the simultaneous electron transfer and ionization is highly sensitive to the quality of a trial initial-state wave function

    Maximum Power Game as a Physical and Social Extension of Classical Games

    Get PDF
    We consider an electric circuit in which the players participate as resistors and adjust their resistance in pursuit of individual maximum power. The maximum power game(MPG) becomes very complicated in a circuit which is indecomposable into serial/parallel components, yielding a nontrivial power distribution at equilibrium. Depending on the circuit topology, MPG covers a wide range of phenomena: from a social dilemma in which the whole group loses to a well-coordinated situation in which the individual pursuit of power promotes the collective outcomes. We also investigate a situation where each player in the circuit has an intrinsic heat waste. Interestingly, it is this individual inefficiency which can keep them from the collective failure in power generation. When coping with an efficient opponent with small intrinsic resistance, a rather inefficient player gets more power than efficient one. A circuit with multiple voltage inputs forms the network-based maximum power game. One of our major interests is to figure out, in what kind of the networks the pursuit for private power leads to greater total power. It turns out that the circuits with the scale-free structure is one of the good candidates which generates as much power as close to the possible maximum total.ope

    Adaptive Boolean Networks and Minority Games with Time--Dependent Capacities

    Full text link
    In this paper we consider a network of boolean agents that compete for a limited resource. The agents play the so called Generalized Minority Game where the capacity level is allowed to vary externally. We study the properties of such a system for different values of the mean connectivity KK of the network, and show that the system with K=2 shows a high degree of coordination for relatively large variations of the capacity level.Comment: 4 pages, 4 figure

    Practical aspects of initiation and use of SGLT2 inhibitors: inpatient and outpatient perspectives

    Get PDF
    In today`s therapy of type 2 diabetes mellitus, SGLT2 inhibitors have taken their rightful place both due to their positive hypoglycemic and outstanding cardiorenometabolic effects. Recent randomized clinical trials, such as DAPA HF, EMPEROR-Reduced and EMPEROR-Preserved, show the benefits of their use in the treatment of patients with chronic heart failure without regard to the status of type 2 diabetes mellitus and so significantly expands the range of use of SGLT2 in the practice of doctors of various specialties. This review presents not only the results of the most significant studies of SGLT2 inhibitors, but also the main approaches to the starting therapy with this class of drugs in various clinical situations, both inpatient and outpatient. In addition, potential adverse events and limitations associated with the use of SGLT2 inhibitors are discussed in detail, which must be taken into account when prescribing in particular patient. The practical aspects of SGLT2 inhibitors` prescription are considered separately through the prism of their safe use in the perioperative and postinfarction periods, as well as during other special conditions. Particular attention is paid to the monitoring of physical and general examination data and laboratory instrumental tests, the consideration of which will minimize adverse events and best benefit for many cardiological, endocrinological and nephrological patients

    Emission Spectrum of a Dipole in a Semi-infinite Periodic Dielectric Structure: Effect of the Boundary

    Full text link
    The emission spectrum of a dipole embedded in a semi-infinite photonic crystal is calculated. For simplicity we study the case in which the dielectric function is sinusoidally modulated only along the direction perpendicular to the boundary surface plane. In addition to oscillations of the emission rate with the distance of the dipole from the interface we also observed that the shape of the emission spectrum srongly depends on the \em initial \em phase of the dielectric modulation. When the direction of light propagation inside the periodic structure is not normal to the boundary surface plane we observed aditional singularities in the emission spectrum, which arise due to different angle-dependence of the Bragg stop-band for TETE and TMTM polarizations.Comment: 14 pages, 6 figures, to appear in Phys Rev

    Localization in non-chiral network models for two-dimensional disordered wave mechanical systems

    Full text link
    Scattering theoretical network models for general coherent wave mechanical systems with quenched disorder are investigated. We focus on universality classes for two dimensional systems with no preferred orientation: Systems of spinless waves undergoing scattering events with broken or unbroken time reversal symmetry and systems of spin 1/2 waves with time reversal symmetric scattering. The phase diagram in the parameter space of scattering strengths is determined. The model breaking time reversal symmetry contains the critical point of quantum Hall systems but, like the model with unbroken time reversal symmetry, only one attractive fixed point, namely that of strong localization. Multifractal exponents and quasi-one-dimensional localization lengths are calculated numerically and found to be related by conformal invariance. Furthermore, they agree quantitatively with theoretical predictions. For non-vanishing spin scattering strength the spin 1/2 systems show localization-delocalization transitions.Comment: 4 pages, REVTeX, 4 figures (postscript

    Strong field approximation within a Faddeev-like formalism for laser-matter interactions

    Get PDF
    We consider the interaction of atomic hydrogen with an intense laser field within the strong-field approximation. By using a Faddeev-like formalism, we introduce a new perturbative series in the binding potential of the atom. As a first test of this new approach, we calculate the electron energy spectrum in the very simple case of a photon energy higher than the ionisation potential. We show that by contrast to the standard perturbative series in the binding potential obtained within the strong field approximation, the first terms of the new series converge rapidly towards the results we get by solving the corresponding time-dependent Schroedinger equation.Comment: 7 pages, 1 figur

    Back-to-back emission of the electrons in double photoionization of helium

    Full text link
    We calculate the double differential distributions and distributions in recoil momenta for the high energy non-relativistic double photoionization of helium. We show that the results of recent experiments is the pioneering experimental manifestation of the quasifree mechanism for the double photoionization, predicted long ago in our papers. This mechanism provides a surplus in distribution over the recoil momenta at small values of the latter, corresponding to nearly "back-to-back" emission of the electrons. Also in agreement with previous analysis the surplus is due to the quadrupole terms of the photon-electron interaction. We present the characteristic angular distribution for the "back-to-back" electron emission. The confirmation of the quasifree mechanism opens a new area of exiting experiments, which are expected to increase our understanding of the electron dynamics and of the bound states structure. The results of this Letter along with the recent experiments open a new field for studies of two-electron ionization not only by photons but by other projectiles, e.g. by fast electrons or heavy ions.Comment: 10 pages, 2 figure
    corecore