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Le livre du consistoire (2013)

Gudrun Petasch

2me protocolle de la justice de la communauté D’Isembourg : commencé le 13˘1 du mois d’aout de lannée 1727 ; contenant 273 feuillets / par Pierre Arnoul Greffier [d]e la justice et communauté (2013)

Gudrun Petasch

Sustainable consumption: towards action and impact. : International scientific conference November 6th-8th 2011, Hamburg - European Green Capital 2011, Germany: abstract volume (2011)

This volume contains the abstracts of all oral and poster presentations of the international scientific conference „Sustainable Consumption – Towards Action and Impact“ held in Hamburg (Germany) on November 6th-8th 2011. This unique conference aims to promote a comprehensive academic discourse on issues concerning sustainable consumption and brings together scholars from a wide range of academic disciplines.

Übersicht über im Herbst 2003 laufende Forschungsprojekte im E-Finance Lab (2003)

Nonthermal phase transitions in semiconductors induced by a femtosecond extreme ultraviolet laser pulse (2013)

Nikita Medvedev Harald O. Jeschke Beata Ziaja

Part of Focus on High Energy Density Physics. In this paper, we present a novel theoretical approach, which allows the study of nonequilibrium dynamics of both electrons and atoms/ions within free-electron laser excited semiconductors at femtosecond time scales. The approach consists of the Monte-Carlo method treating photoabsorption, high-energy-electron and core-hole kinetics and relaxation processes. Low-energy electrons localized within the valence and conduction bands of the target are treated with a temperature equation, including source terms, defined by the exchange of energy and particles with high-energy electrons and atoms. We follow the atomic motion with the molecular dynamics method on the changing potential energy surface. The changes of the potential energy surface and of the electron band structure are calculated at each time step with the help of the tight-binding method. Such a combination of methods enables investigation of nonequilibrium structural changes within materials under extreme ultraviolet (XUV) femtosecond irradiation. Our analysis performed for diamond irradiated with an XUV femtosecond laser pulse predicts for the first time in this wavelength regime the nonthermal phase transition from diamond to graphite. Similar to the case of visible light irradiation, this transition takes place within a few tens of femtoseconds and is caused by changes of the interatomic potential induced by ultrafast electronic excitations. It thus occurs well before the heating stimulated by electron–phonon coupling starts to play a role. This allows us to conclude that this transition is nonthermal and represents a general mechanism of the response of solids to ultrafast electron excitations.

Zoo Basel Newsletter. 2013, Juni (2013)

Integer point sets minimizing average pairwise L1 distance: What is the optimal shape of a town? (2010)

Erik D. Demaine Sándor P. Fekete Günter Rote Nils Schweer Daria Schymura Mariano Zelke

An n-town, n[is an element of]N , is a group of n buildings, each occupying a distinct position on a 2-dimensional integer grid. If we measure the distance between two buildings along the axis-parallel street grid, then an n-town has optimal shape if the sum of all pairwise Manhattan distances is minimized. This problem has been studied for cities, i.e., the limiting case of very large n. For cities, it is known that the optimal shape can be described by a differential equation, for which no closed-form solution is known. We show that optimal n-towns can be computed in O(n[superscript 7.5]) time. This is also practically useful, as it allows us to compute optimal solutions up to n=80.

CAST constraints on the axion-electron coupling (2013)

Klaus Barth Alexander Belov Berta Beltran Heinrich Bräuninger José Manuel Carmona Juan I. Collar Theopisti Dafni Martyn Davenport Luigi Di Lella Christos Eleftheriadis Jakob Englhauser George Fanourakis Ester Ferrer-Ribas Horst Fischer Jürgen Franz Peter Friedrich Javier Galán J. A. García Theodoros Geralis Ioanis Giomataris Sergei Gninenko Héctor Gómez Michael D. Hasinoff Fritz Herbert Heinsius Dieter H.H. Hoffmann Igor Garcia Irastorza Joachim Jacoby Kresimir Jakovčić Donghwa Kang Kay Königsmann Rainer Kotthaus Konstantinos Kousouris Milica Krčmar M. Kuster Biljana Lakić Anastasios Liolios Ante Ljubičić Gerhard Lutz Gloria Luzón David W. Miller Thomas Papaevangelou Mike J. Pivovaroff Georg Raffelt Javier Redondo Hans Riege A. Rodríguez Jaime Ruz Ilias Savvidis Yannis Semertzidis Laura Stewart Karl van Bibber Joaquin D. Vieira José A. Villar Julia K. Vogel Louis Walckiers Konstantin Zioutas

In non-hadronic axion models, which have a tree-level axion-electron interaction, the Sun produces a strong axion flux by bremsstrahlung, Compton scattering, and axiorecombination, the “BCA processes.” Based on a new calculation of this flux, including for the first time axio-recombination, we derive limits on the axion-electron Yukawa coupling gae and axion-photon interaction strength ga using the CAST phase-I data (vacuum phase). For ma <~ 10 meV/c2 we find ga gae < 8.1 × 10−23 GeV−1 at 95% CL. We stress that a next-generation axion helioscope such as the proposed IAXO could push this sensitivity into a range beyond stellar energy-loss limits and test the hypothesis that white-dwarf cooling is dominated by axion emission.

4-Nitrophenyl 2-chlorobenzoate (2012)

Asma Iqbal Toheed Akhter Humaira Masood Siddiqi Zareen Akhter Michael Bolte

The aromatic rings in the title compound, C13H8ClNO4, enclose a dihedral angle of 39.53 (3)°. The nitro group is almost coplanar with the ring to which it is attached [dihedral angle = 4.31 (1)°]. In the crystal, molecules are connected by C-H...O hydrogen bonds into chains running along [001]. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 A°; R factor = 0.044; wR factor = 0.105; data-to-parameter ratio = 18.9.

Electron Supersurface Scattering On Polycrystalline Au (2013)

Wolfgang S. M. Werner Mihály Novák Francesc Salvat–Pujol Josef Zemek Petr Jiricek

Supersurface electron scattering, i.e., electron energy losses and associated deflections in vacuum above the surface of a medium, is shown to contribute significantly to electron spectra. We have obtained experimental verification (in absolute units) of theoretical predictions that the angular distribution of the supersurface backscattering probability exhibits strong oscillations which are anticorrelated with the generalized Ramsauer-Townsend minima in the backscattering probability. We have investigated 500-eV electron backscattering from an Au surface for an incidence angle of 70° and scattering angles between 37° and 165°. After removing the contribution of supersurface scattering from the experimental data, the resulting angular and energy distribution agrees with the Landau-Goudsmit-Saunderson (LGS) theory, which was proposed about 60 years ago, while the raw data are anticorrelated with LGS theory. This result implies that supersurface scattering is an essential phenomenon for quantitative understanding of electron spectra.

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