Workshop on Cosmogenic Nuclides

Abstracts of papers presented at the Workshop on Cosmogenic Nuclides are compiled. The major topic areas covered include: new techniques for measuring nuclides such as tandem accelerator and resonance mass spectrometry; solar modulation of cosmic rays; pre-irradiation histories of extraterrestrial materials; terrestrial studies; simulations and cross sections; nuclide production rate calculations; and meteoritic nuclides

Questions and responses in Dutch conversations

Based on an analysis of 350 questions and their responses in a corpus of ordinary interactions, this paper gives a descriptive overview of the ways Dutch interactants formulate their utterances to make them recognizable as doing questioning and the options they rely on to respond to these questions. I describe the formal options for formulating questions and responses in Dutch and the range of social actions (e.g. requests for information, requests for confirmation) that are implemented through questions in the corpus. Finally, I focus on answer design and discuss some of the coherence relations between questions, answers, and social actions. Questions that are asked to elicit information are associated with the more prototypical, lexico-morpho-syntactically defined question type such as polar interrogatives and, mainly, content questions. Most polar questions with declarative syntax are not primarily concerned with obtaining information but with doing other kinds of social action

G+++ Invariant Formulation of Gravity and M-Theories: Exact BPS Solutions

We present a tentative formulation of theories of gravity with suitable matter content, including in particular pure gravity in D dimensions, the bosonic effective actions of M-theory and of the bosonic string, in terms of actions invariant under very-extended Kac-Moody algebras G+++. We conjecture that they host additional degrees of freedom not contained in the conventional theories. The actions are constructed in a recursive way from a level expansion for all very-extended algebras G+++. They constitute non-linear realisations on cosets, a priori unrelated to space-time, obtained from a modified Chevalley involution. Exact solutions are found for all G+++. They describe the algebraic properties of BPS extremal branes, Kaluza-Klein waves and Kaluza-Klein monopoles. They illustrate the generalisation to all G+++ invariant theories of the well-known duality properties of string theories by expressing duality as Weyl invariance in G+++. Space-time is expected to be generated dynamically. In the level decomposition of E8+++ = E11, one may indeed select an A10 representation of generators Pa which appears to engender space-time translations by inducing infinite towers of fields interpretable as field derivatives in space and time.Comment: Latex 45 pages, 1 figure. Discussion on pages 19 and 20 altered. Appendix B amplified. 4 footnotes added. 2 references added. Acknowledgments updated. Additional minor correction

Iterative procedure for computing accessible information in quantum communication

We present an iterative algorithm that finds the optimal measurement for extracting the accessible information in any quantum communication scenario. The maximization is achieved by a steepest-ascent approach toward the extremal point, following the gradient uphill in sufficiently small steps. We apply it to a simple ad-hoc example, as well as to a problem with a bearing on the security of a tomographic protocol for quantum key distribution.Comment: REVTeX, 4 pages, 1 figure, 1 tabl

Abrupt and gradual changes of information through the Kane solid state computer

The susceptibility of the transformed information to the filed and system parameters is investigated for the Kane solid state computer. It has been shown, that the field polarization and the initial state of the system play the central roles on the abrupt and gradual quench of the purity and the fidelity. If the field and the initial state are in different polarizations, then the purity and the fidelity decrease abruptly, while for the common polarization the decay is gradual and smooth. For some class of initial states one can send the information without any loss. Therefore, by controlling on the devices one can increase the time of safe communication, reduce the amount of exchange information between the state and its environment and minimize the purity decrease rate

Simulation experiments for gamma-ray mapping of planetary surfaces: Scattering of high-energy neutrons

The concentration and distribution of certain elements in surface layers of planetary objects specify constraints on models of their origin and evolution. This information can be obtained by means of remote sensing gamma-ray spectroscopy, as planned for a number of future space missions, i.e., Mars, Moon, asteroids, and comets. To investigate the gamma-rays made by interactions of neutrons with matter, thin targets of different composition were placed between a neutron-source and a high-resolution germanium spectrometer. Gamma-rays in the range of 0.1 to 8 MeV were accumulated. In one set of experiments a 14-MeV neutron generator using the T(d,n) reaction as neutron-source was placed in a small room. Scattering in surrounding walls produced a spectrum of neutron energies from 14 MeV down to thermal. This complex neutron-source induced mainly neutron-capture lines and only a few scattering lines. As a result of the set-up, there was a considerable background of discrete lines from surrounding materials. A similar situation exists under planetary exploration conditions: gamma-rays are induced in the planetary surface as well as in the spacecraft. To investigate the contribution of neutrons with higher energies, an experiment for the measurement of prompt gamma radiation was set up at the end of a beam-line of an isochronous cyclotron

Heimische Drosophila Parasitoide für die natürliche Regulierung der Kirschessigfliege, Drosophila suzukii M., einem invasiven Schaderreger im ökologischen Obstanbau

The invasive fruit pest Drosophila suzukii from Asia currently spreads in Germany without being regulated by adapted specific natural enemies. Due to its polyphagous nature, D. suzukii causes high risk in various soft fruit crops, especially since weather and wild host plants provide suitable conditions for population outbreaks. Ongoing research aims to identify native parasitoids of Drosophilidae in Germany and tries to assess their ability for natural control as well as their suitability for being used as biological control agents in pest management of D. suzukii

QCD Corrections to Vector-Boson Fusion Processes in Warped Higgsless Models

We discuss the signatures of a representative Higgsless model with ideal fermion delocalization in vector-boson fusion processes, focusing on the gold- and silver-plated decay modes of the gauge bosons at the CERN-Large Hadron Collider. For this purpose, we have developed a fully-flexible parton-level Monte-Carlo program, which allows for the calculation of cross sections and kinematic distributions within experimentally feasible selection cuts at NLO-QCD accuracy. We find that Kaluza-Klein resonances give rise to very distinctive distributions of the decay leptons. Similar to the Standard Model case, within the Higgsless scenario the perturbative treatment of the vector-boson scattering processes is under excellent control.Comment: 22 pages, 20 figure