Technical University of Dortmund

About: Technical University of Dortmund is a education organization based out in Dortmund, Nordrhein-Westfalen, Germany. It is known for research contribution in the topics: Context (language use) & Large Hadron Collider. The organization has 13028 authors who have published 27666 publications receiving 615557 citations. The organization is also known as: Dortmund University & University of Dortmund.

Carleman Estimates and Absence of Embedded Eigenvalues

Abstract: Let L = −Δ− W be a Schrodinger operator with a potential \(W\in L^{\frac{n+1}{2}}(\mathbb{R}^n)\), \(n \geq 2\) We prove that there is no positive eigenvalue The main tool is an \(L^{p}-L^{p^\prime}\) Carleman type estimate, which implies that eigenfunctions to positive eigenvalues must be compactly supported The Carleman estimate builds on delicate dispersive estimates established in [7] We also consider extensions of the result to variable coefficient operators with long range and short range potentials and gradient potentials

Study of resonances in exclusive B decays to D̄(*)D(*)K

Abstract: We present a study of resonances in exclusive decays of $B$ mesons to $\bar{D}^{(*)} D^{(*)} K$. We report the observation of the decays $B \to \Dbar^{(*)} D^+_{s1}(2536)$ where the $D^+_{s1}(2536)$ is reconstructed in the $D^{*0}K^+$ and $D^{*+} K^0_S$ decay channels. We report also the observation of the decays $B \to \psi(3770) K$ where the $\psi(3770)$ decays to $\Dbar^0 D^0$ and $D^- D^+$. In addition, we present the observation of an enhancement for the $\Dbar^{*0} D^0$ invariant mass in the decays $B \to \Dbar^{*0} D^0 K$, at a mass of $(3875.1 {}^{+0.7}_{-0.5} \pm 0.5)$ MeV/$c^2$ with a width of $(3.0 {}^{+1.9}_{-1.4} \pm 0.9)$ MeV (the first errors are statistical and the second are systematic). Branching fractions and spin studies are shown for the three resonances. The results are based on 347 fb$^{-1}$ of data collected with the BaBar detector at the PEP-II $B$ factory.

Angle-resolved photoemission from polar and nonpolar zinc oxide surfaces

Abstract: We report the first angle-resolved photoemission spectra (ARPES) of polar and nonpolar surfaces of an ionic wurtzite-type compound semiconductor. We present experimental results obtained at photon energies between 20 and 80 eV on the polar zinc and oxygen and the nonpolar ($10\overline{1}0$) surfaces of ZnO and identify surface-induced features by comparison with recent theoretical calculations. Comparison between ARPES experiments and theory confirms the determination of the surface-atom geometry at $\mathrm{ZnO}(10\overline{1}0)$ by low-energy electron diffraction studies.