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A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of ground-based detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers.

SO2 plays an important role in the atmospheric chemistry of the Earth, Venus, and Io. This paper presents photoabsorption cross sections of SO2 from 213 to 325 nm at 198 K, encompassing the (C) over tilde B-1(2) - (X) over tilde (1)A(1) and (B) over tilde B-1(1) - (X) over tilde (1)A(1) electronic bands. These measurements are part of a series of measurements over the 160 to 300 K temperature rang

Transition isotope shifts of 3s-3p transitions in Ne II and Ne III are measured in Fourier transform spectra from a hollow-cathode source. Accurate absolute line-center positions of the Ne-20 isotope are derived for the purpose of tertiary wavelength standards in the region 2000-5000 angstrom. A robust statistical treatment is applied, yielding line-position uncertainties that are lower than for t

The 3s(2)3p(2 3)P(1.2)-3s3p(3) S-5(2) intercombination lines for Si-like Rh have been investigated using the techniques of beam-foil spectroscopy. Two lines have been identified as belonging to these transitions having, however, different wavelengths from what would be expected based on published iso-electronic trends. The identifications suggested here are strengthened by requirements on (a) the

Gas turbines, in simple and combined cycle, are common and economically profitable on the power generating market today. Several new cycles have been proposed as future competing technologies, but all studies about these cycles have, so far, been paperwork. The requirements for these new cycles are better efficiency than those of today, provide better flexibility, offer short start up times, less

In this paper we investigate the performance of a Fourier based algorithm for fast subpixel shift determination of two mutually shifted images subjected to noise. The algorithm will be used for Shack-Hartmann based adaptive optics correction of images of an extended object subjected to dynamical atmospheric fluctuations. The performance of the algorithm is investigated both analytically and by Mon

Using high-resolution spectra of nearby F and G dwarf stars, we have investigated the detailed abundance and age structure of the Hercules stream. We find that the stars in the stream have a wide range of stellar ages, metallicities, and element abundances. By comparing to existing samples of stars in the solar neighborhood with kinematics typical of the Galactic thin and thick disks, we find that

Accuracies reached in space astrometry now permit. the accurate determination of astrometric radial velocities. without any use of spectroscopy. Knowing this true stellar motion, spectral shifts; intrinsic to stellar atmospheres can be identified, for instance gravitational redshifts and those caused by, velocity fields on stellar surfaces. The astrometric accuracy is independent. of any spectral

Among the science challenges of the Extremely Large Telescopes (ELTs),four object types are studied for performance with a 50 m ELT withadaptive optics (AO), Euro50. Emphasis is on planetary systems and verydistant objects. For planetary systems and their evolution, we examinehigh resolution imaging of the nuclei of comets and high-resolutionimaging, photometry and low and intermediate resolution

Solar mean magnetic field (SMMF) measurements from the Wilcox Solar Observatory and with the SOHO/MDI instrument are described and analyzed. Even though two completely different methods of observation are used, the two data sets obtained show a strong similarity. Using continuous wavelet transforms, SMMF variability is found at a number of temporal scales. Detected SMMF signals with a 1–2 year per

Using a numerical simulation of compressible convection with radiativetransfer mimicking the solar photosphere, we compare the velocity fieldderived from granule motions to the actual velocity field of the plasma.We thus test the idea that granules may be used to trace large-scalevelocity fields at the sun's surface. Our results show that this isindeed the case provided the scale separation is suf

We report that the density profiles of globular cluster (GC) systems in a sample of 17 early-Type galaxies (ETGs) show breaks at the radii where the gravitational acceleration exerted by the stars equals the galactic acceleration scale a0 known from the radial acceleration relation or the modified Newtonian dynamics (MOND). The match with the other characteristic radii in the galaxy is not that cl

We investigate the dissolution process of star clusters embedded in an external tidal field and harboring a subsystem of stellar-mass black hole. For this purpose we analyzed the MOCCA models of real star clusters contained in the Mocca Survey Database I. We showed that the presence of a stellar-mass black hole subsystem in tidally filling star cluster can lead to abrupt cluster dissolution connec

The Cherenkov Telescope Array (CTA) will be the next generation very-high-energy gamma-ray observatory. CTA is expected to provide substantial improvement in accuracy and sensitivity with respect to existing instruments thanks to a tenfold increase in the number of telescopes and their state-of-the-art design. Detailed Monte Carlo simulations are used to further optimise the number of telescopes a

Ansvarsförsäkringens primära syfte har i svensk rätt alltid varit att täcka det ansvar för skada som kan åläggas den försäkrade gentemot tredje man. Med tiden har dock ansvarsförsäkringens indirekta funktion att trygga den skadeli-dandes rätt till skadestånd fått en ökad betydelse. Som ett led i att förbättra den skadelidandes kompensationsmöjligheter har därför den skadelidande i FAL (2005:104) g

Partikelfysikens standardmodell är en av de mest exakta modellerna inom fysiken. Den beskriver interaktionerna mellan fundamentala partiklar som kvarkar och leptoner, hur Higgspartikeln ger massa till andra partiklar och tre av universums fyra fundamentala krafter: elektromagnetism, svag växelverkan och stark kärnkraft. Tyvärr finns det frågor som inte ens standardmodellen kan svara på. "Varf

Ecoist AB utvecklar en prototyp till en trehjulig elbil för två personer. Två komponenter till fordonet har undersökts: den övre bärarmen i den främre hjulupphängningen och en bussning som sitter i denna bärarm. Målet med examensarbetet har varit att se om det finns några funktionella eller ekonomiska fördelar med att tillverka dessa genom 3D-printing. Olika sätt att framställa komponenterna har u

Jet quenching in heavy ion collisions and in particular the sub-structure of quenched jets are promising tools for investigating the microscopic processes underlying jet quenching and the background medium's response to energy and momentum depositions. A quantitative understanding of the data can, however, be complicated by the presence of initial state radiation in reconstructed jets. Using an ex

Chiral Perturbation Theory is a useful tool to aid in performing the various extrapolations needed in lattice QCD calculations of physical quantities. These include extrapolations in quark mass, finite lattice spacing and finite size of the lattice. Especially the latter will becomemore important when the quark masses on the lattice become smaller. Here we develop the needed two-loop integrals at