Potsdam, Germany
Potsdam, Germany

Time filter

Source Type

Adrian-Martinez S.,Polytechnic University of Valencia | Albert A.,Upper Alsace University | Andre M.,University of Barcelona | Anton G.,Friedrich - Alexander - University, Erlangen - Nuremberg | And 138 more authors.
Journal of Cosmology and Astroparticle Physics | Year: 2015

The ANTARES telescope is well-suited for detecting astrophysical transient neutrino sources as it can observe a full hemisphere of the sky at all times with a high duty cycle. The background due to atmospheric particles can be drastically reduced, and the point-source sensitivity improved, by selecting a narrow time window around possible neutrino production periods. Blazars, being radio-loud active galactic nuclei with their jets pointing almost directly towards the observer, are particularly attractive potential neutrino point sources, since they are among the most likely sources of the very high-energy cosmic rays. Neutrinos and gamma rays may be produced in hadronic interactions with the surrounding medium. Moreover, blazars generally show high time variability in their light curves at different wavelengths and on various time scales. This paper presents a time-dependent analysis applied to a selection of flaring gamma-ray blazars observed by the FERMI/LAT experiment and by TeV Cherenkov telescopes using five years of ANTARES data taken from 2008 to 2012. The results are compatible with fluctuations of the background. Upper limits on the neutrino fluence have been produced and compared to the measured gamma-ray spectral energy distribution. © 2015 IOP Publishing Ltd and Sissa Medialab srl .

Spath J.,Fraunhofer Institute for Secure Information Technology | Quang Do L.N.,Universitadie | Ali K.,TU Darmstadt | Bodden E.,Universitadie
Leibniz International Proceedings in Informatics, LIPIcs | Year: 2016

Many current program analyses require highly precise pointer information about small, targeted parts of a given program. This motivates the need for demand-driven pointer analyses that compute information only where required. Pointer analyses generally compute points-to sets of program variables or answer boolean alias queries. However, many client analyses require richer pointer information. For example, taint and typestate analyses often need to know the set of all aliases of a given variable under a certain calling context. With most current pointer analyses clients must compute such information through repeated points-to or alias queries, increasing complexity and computation time for them. This paper presents Boomerang, a demand-driven, flow-, field-, and context-sensitive pointer analysis for Java programs. Boomerang computes rich results that include both the possible allocation sites of a given pointer (points-to information) and all pointers that can point to those allocation sites (alias information). For increased precision and scalability, clients can query Boomerang with respect to particular calling contexts of interest. Our experiments show that Boomerang is more precise than existing demand-driven pointer analyses. Additionally, using Boomerang, the taint analysis Flow Droid issues up to 29.4x fewer pointer queries compared to using other pointer analyses that return simpler pointer information. Furthermore, the search space of Boomerang can be significantly reduced by requesting calling contexts from the client analysis. © J. Spadie;th, L. Nguyen Quang Do, K. Ali, and E. Bodden; licensed under Creative Commons License CC-BY.

Welsch S.,Universitadie | Bodensteiner M.,Universitadie | Dusek M.,ASCR Institute of Physics Prague | Sierka M.,Humboldt University of Berlin | Scheer M.,Universitadie
Chemistry - A European Journal | Year: 2010

A new soluble In+ source containing the very weakly coordinating anion [Al{OC(CF3)3}4]- was developed. In reaction with a P2 ligand complex an unprecedented tetracationic aggregate is formed featuring a short In···In distance (see picture). Polymeric strands arising from a reaction with a cyclo-P3 ligand complex exhibit a novel coordination mode for P 3 units. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Loading Universitadie collaborators
Loading Universitadie collaborators