Hard exclusive photoproduction of Φ\Phi and J/ΨJ/\Psi mesons

We present predictions for differential cross sections for the reaction $\gamma p \to \Phi p$ and give an outlook to which extent our calculations may be generalized to the photoproduction of $J/\Psi$ mesons. Our results are obtained within perturbative QCD treating the proton as a quark-diquark system.Comment: 4 pages, 1 figure, uses Elsevier style espcrc1.st

Longitudinally Polarized Photoproduction of Inclusive Hadrons at Fixed-Target Experiments

We present a detailed phenomenological study of spin-dependent single-inclusive high-p_T hadron photoproduction with particular emphasis on the kinematics relevant for the Compass and Hermes fixed-target experiments. We carefully examine the theoretical uncertainties associated with the only moderate transverse momenta accessible in such measurements and analyze the sensitivity of the relevant spin asymmetries to the gluon polarization in the nucleon as well as to the completely unknown parton content of circularly polarized photons.Comment: 12 pages, 14 figures; final version to appear in EPJC; comparison to E155 data and references adde

The uniqueness of the solution of the Schrodinger equation with discontinuous coefficients

Consider the Schroeodinger equation: - Du(x) - l(x)u + s(x)u = 0, where D is the Laplacian, l(x) > 0 and s(x) is dominated by l(x). We shall extend the celebrated Kato's result on the asymptotic behavior of the solution to the case where l(x) has unbounded discontinuity. The result will be used to establish the limiting absorption principle for a class of reduced wave operators with discontinuous coefficients.Comment: 29 (twenty-nine) pages; no figures; to appear in Reviews of Mathematical Physic

Psychiatrische Versorgungsepidemiologie

Zusammenfassung: Psychiatrische Versorgungsepidemiologie untersucht die Situation der Versorgung von Menschen mit psychischen Erkrankungen unter Alltagsbedingungen. Psychiatrische Versorgungsstrukturen in Deutschland haben sich in den letzten Jahrzehnten weg von stationärer Behandlung mit teilweise mehrmonatiger Aufenthaltsdauer hin zu dezentralen teilstationären und ambulanten Angeboten entwickelt. Derzeit hat sich die Verschiebung von Behandlungskapazitäten zwischen den Settings stabilisiert und der Schwerpunkt der Versorgungsplanung liegt mehr auf der Entwicklung von möglichst flächendeckenden Strukturen zur Vernetzung der oftmals noch fragmentierten und streng an den Sektorgrenzen orientierten Versorgungslandschaft. Der Versorgungsbedarf hängt mit einer Vielzahl Faktoren wie den epidemiologischen Daten der Bevölkerung, der Inanspruchnahme und den gesundheitspolitischen Rahmenbedingungen zusammen. Ob die derzeitigen Versorgungsstrukturen den aktuellen Bedarf abdecken und den Qualitätsansprüchen genügen, ist aufgrund der spärlichen Datenlage und dem Mangel an Referenzmaßstäben nur schwer zu beurteilen. Ein substanzieller Ausbau psychiatrischer Versorgungsforschung in den kommenden Jahren ist hierfür grundlegend erforderlic

Global Regularity of Solution for General Degenerate Parabolic Equations in 1-D

AbstractThis paper considers the Cauchy problem for the general degenerate parabolic equations (1.1) with initial data (1.2). In the critical condition meas{u:g(u)=0{=0 we obtain the regular estimateG(u)∈C(1), whereG(u)=∫u0g(s)ds. A new maximum principle is introduced to obtain the estimate and is applied to some special equations such as prous media equation, an infiltration equation to obtain the optimal estimate |(um−1)x|⩽M. Finally an interesting equation related to the Broadwell model (whereg(u) has two zero points) is studied and a uniquely regular solutionu∈C(1)is obtained. Moreover the estimatesux⩽ρ(f(u)−u2)/g(u) andρ⩾infxρ0(x)/(1+4t(infxρ0(x))) are proved for the solution of the Navier–Stokes equations corresponding to the Broadwell model

A priori convergence estimates for a rough Poisson-Dirichlet problem with natural vertical boundary conditions

Stents are medical devices designed to modify blood flow in aneurysm sacs, in order to prevent their rupture. Some of them can be considered as a locally periodic rough boundary. In order to approximate blood flow in arteries and vessels of the cardio-vascular system containing stents, we use multi-scale techniques to construct boundary layers and wall laws. Simplifying the flow we turn to consider a 2-dimensional Poisson problem that conserves essential features related to the rough boundary. Then, we investigate convergence of boundary layer approximations and the corresponding wall laws in the case of Neumann type boundary conditions at the inlet and outlet parts of the domain. The difficulty comes from the fact that correctors, for the boundary layers near the rough surface, may introduce error terms on the other portions of the boundary. In order to correct these spurious oscillations, we introduce a vertical boundary layer. Trough a careful study of its behavior, we prove rigorously decay estimates. We then construct complete boundary layers that respect the macroscopic boundary conditions. We also derive error estimates in terms of the roughness size epsilon either for the full boundary layer approximation and for the corresponding averaged wall law.Comment: Dedicated to Professor Giovanni Paolo Galdi 60' Birthda

2D velocity fields of simulated interacting disc galaxies

We investigate distortions in the velocity fields of disc galaxies and their use to reveal the dynamical state of interacting galaxies at different redshift. For that purpose, we model disc galaxies in combined N-body/hydrodynamic simulations. 2D velocity fields of the gas are extracted from these simulations which we place at different redshifts from z=0 to z=1 to investigate resolution effects on the properties of the velocity field. To quantify the structure of the velocity field we also perform a kinemetry analysis. If the galaxy is undisturbed we find that the rotation curve extracted from the 2D field agrees well with long-slit rotation curves. This is not true for interacting systems, as the kinematic axis is not well defined and does in general not coincide with the photometric axis of the system. For large (Milky way type) galaxies we find that distortions are still visible at intermediate redshifts but partly smeared out. Thus a careful analysis of the velocity field is necessary before using it for a Tully-Fisher study. For small galaxies (disc scale length ~2 kpc) even strong distortions are not visible in the velocity field at z~0.5 with currently available angular resolution. Therefore we conclude that current distant Tully-Fisher studies cannot give reliable results for low-mass systems. Additionally to these studies we confirm the power of near-infrared integral field spectrometers in combination with adaptive optics (such as SINFONI) to study velocity fields of galaxies at high redshift (z~2).Comment: 12 pages, 18 figures, accepted for publication in A&A, high resolution version can be found at http://astro.uibk.ac.at/~thomas/kronberger.pd

Realization of a semiconductor-based cavity soliton laser

The realization of a cavity soliton laser using a vertical-cavity surface-emitting semiconductor gain structure coupled to an external cavity with a frequency-selective element is reported. All-optical control of bistable solitonic emission states representing small microlasers is demonstrated by injection of an external beam. The control scheme is phase-insensitive and hence expected to be robust for all-optical processing applications. The motility of these structures is also demonstrated