Photometric redshift accuracy in AKARI Deep SurveysWe investigate the photometric redshift accuracy achievable with the AKARI infrared data in deep multi-band surveys, such as in the North Ecliptic Pole field. We demonstrate that the passage of…M. Negrello, S. Serjeant, C. Pearson et al.·Nov 25, 2008SaveLearn
On the origin of white dwarfs with carbon-dominated atmospheres: the case of H1504+65We explore different evolutionary scenarios to explain the helium deficiency observed in H1504+65, the most massive known PG1159 star. We concentrate mainly on the possibility that this star could be…L. G. Althaus, A. H. Córsico, S. Torres et al.·Nov 25, 2008SaveLearn
Trigonometric parallaxes of ten ultracool subdwarfsWe measured absolute trigonometric parallaxes and proper motions with respect to many background galaxies for a sample of ten ultracool subdwarfs. The observations were taken in the H-band with the…E. Schilbach, S. Roeser, R. -D. Scholz·Nov 25, 2008SaveLearn
Southern Cosmology Survey III: QSO's from Combined GALEX and Optical PhotometryWe present catalogs of QSO candidates selected using photometry from GALEX combined with SDSS in the Stripe 82 region and Blanco Cosmology Survey (BCS) near declination -55 degrees. The SDSS region…Raul Jimenez, David N. Spergel, Michael D. Niemack et al.·Nov 25, 2008SaveLearn
Dark Energy and Modified GravityExplanations of the late-time cosmic acceleration within the framework of general relativity are plagued by difficulties. General relativistic models are mostly based on a dark energy field with…Ruth Durrer, Roy Maartens·Nov 25, 2008SaveLearn
Abundances of massive stars: some recent developmentsThanks to their usefulness in various fields of astrophysics (e.g. mixing processes in stars, chemical evolution of galaxies), the last few years have witnessed a large increase in the amount of…T. Morel·Nov 25, 2008SaveLearn
Collapsing Hot Molecular Cores: A Model for the Dust Spectrum and Ammonia Line Emission of the G31.41+0.31 Hot CoreWe present a model aimed to reproduce the observed spectral energy distribution (SED) as well as the ammonia line emission of the G31.41+0.31 hot core. The core is modeled as an infalling envelope…Mayra Osorio, Guillem Anglada, Susana Lizano et al.·Nov 25, 2008SaveLearn
The core helium flash revisited: II. Two and three-dimensional hydrodynamic simulationsWe study turbulent convection during the core helium flash close to its peak by comparing the results of two and three-dimensional hydrodynamic simulations. We use a multidimensional Eulerian…M. Mocak, E. Mueller, A. Weiss et al.·Nov 25, 2008SaveLearn
CI and CO in nearby galaxy centers: the bright galaxies NGC1068 (M77), NGC2146, NGC3079, NGC4826 (M64), and NGC7469Maps and measurements of the J=1-0, J=2-1, J=3-2, J=4-3 12CO, the J=1-0, J=2-1, and J=3-2 13CO lines in the central arcminute squared of NGC1068, NGC2146, NGC3079, NGC4826, and NGC7469, as well as…F. P. Israel·Nov 25, 2008SaveLearn
Gamma-rays from the vicinity of accreting neutron stars inside compact high-mass X-ray binariesDense wind of a massive star can be partially captured by a neutron star (NS) inside a compact binary system. Depending on the parameters of NS and the wind, the matter can penetrate the inner NS…W. Bednarek·Nov 25, 2008SaveLearn
Resolved 24.5 micron emission from massive young stellar objectsMassive young stellar objects (MYSO) are surrounded by massive dusty envelopes. Our aim is to establish their density structure on scales of ~1000 AU, i.e. a factor 10 increase in angular resolution…W. J. de Wit, M. G. Hoare, T. Fujiyoshi et al.·Nov 25, 2008SaveLearn
Two ~35 day clocks in Her X-1: evidence for neutron star free precessionWe present evidence for the existence of two ~35 day clocks in the Her X-1/HZ Her binary system. ~35 day modulations are observed 1) in the Turn-On cycles with two on- and two off-states, and 2) in…R. Staubert, D. Klochkov, K. Postnov et al.·Nov 25, 2008SaveLearn
Constraints on black hole accretion in V PuppisIn light of the recent suggestion that the nearby eclipsing binary star system V Puppis has a dark companion on a long orbit, we present the results of radio and X-ray observations of it. We find an…Thomas J. Maccarone, Robert P. Fender, Christian Knigge et al.·Nov 25, 2008SaveLearn
Stellar mass estimates in early-type galaxies: procedures, uncertainties and models dependenceThe aim of the present paper is to quantify the dependence of the estimates of luminosities and stellar mass of early-type galaxies on the different models and model parameters which can be used to…Marcella Longhetti, Paolo Saracco·Nov 25, 2008SaveLearn
A New Diagnostic Method for Assessment of Stellar Stratification in Star ClustersWe propose a new method for the characterization of stellar stratification in stellar systems. The method uses the mean-square radius (also called the Spitzer radius) of the system as a diagnostic…Dimitrios A. Gouliermis, Richard de Grijs, Yu Xin·Nov 25, 2008SaveLearn
Analytic Spectra of CMB Anisotropies and Polarization Generated by Relic Gravitational Waves with Modification due to Neutrino Free-StreamingWe present an analytical calculation of the spectra of CMB anisotropies and polarizations generated by relic gravitational waves (RGWs). As a substantial extension to the previous studies, three new…T. Y. Xia, Y. Zhang·Nov 25, 2008SaveLearn
A new determination of the orbit and masses of the Be binary system delta ScorpiiThe binary star delta Sco (HD143275) underwent remarkable brightening in the visible in 2000, and continues to be irregularly variable. The system was observed with the Sydney University Stellar…W. J. Tango, J. Davis, A. P. Jacob et al.·Nov 25, 2008SaveLearn
The origin of redshift asymmetries: How LambdaCDM explains anomalous redshiftSeveral authors have found a statistically significant excess of galaxies with higher redshifts relative to the group centre, so-called discordant redshifts, in particular in groups where the…Sami-Matias Niemi, Mauri Valtonen·Nov 24, 2008SaveLearn
SDSS J080449.49+161624.8: A peculiar AM CVn star from a colour-selected sample of candidatesWe describe a spectroscopic survey designed to uncover an estimated ~40 AM CVn stars hiding in the photometric database of the Sloan Digital Sky Survey (SDSS). We have constructed a relatively small…G. H. A. Roelofs, P. J. Groot, D. Steeghs et al.·Nov 24, 2008SaveLearn
Galaxy Zoo: Disentangling the Environmental Dependence of Morphology and ColourWe analyze the environmental dependence of galaxy morphology and colour with two-point clustering statistics, using data from the Galaxy Zoo, the largest sample of visually classified morphologies…Ramin A. Skibba, Steven P. Bamford, Robert C. Nichol et al.·Nov 24, 2008SaveLearn
The Case for a 700+ GeV WIMP: Cosmic Ray Spectra from PAMELA, Fermi and ATICMultiple lines of evidence indicate an anomalous injection of high-energy e+- in the Galactic halo. The recent e+ fraction spectrum from the Payload for Antimatter Matter Exploration and…Ilias Cholis, Gregory Dobler, Douglas P. Finkbeiner et al.·Nov 24, 2008SaveLearn
FIRST "Winged" and X-shaped Radio Source Candidates: II. New RedshiftsWe report optical spectroscopic observations of X-shaped radio sources with the Hobby-Eberly Telescope and Multiple-Mirror Telescope, focused on the sample of candidates from the FIRST survey…C. C. Cheung, Stephen E. Healey, Hermine Landt et al.·Nov 24, 2008SaveLearn
CMBPol Mission Concept Study: Probing Inflation with CMB PolarizationWe summarize the utility of precise cosmic microwave background (CMB) polarization measurements as probes of the physics of inflation. We focus on the prospects for using CMB measurements to…Daniel Baumann, Mark G. Jackson, Peter Adshead et al.·Nov 24, 2008SaveLearn
Gravity with Perturbative Constraints: Dark Energy Without New Degrees of FreedomMajor observational efforts in the coming decade are designed to probe the equation of state of dark energy. Measuring a deviation of the equation-of-state parameter w from -1 would indicate a dark…Alan Cooney, Simon DeDeo, Dimitrios Psaltis·Nov 24, 2008SaveLearn
Zonal Flows and Long-Lived Axisymmetric Pressure Bumps in Magnetorotational TurbulenceWe study the behavior of magnetorotational turbulence in shearing box simulations with a radial and azimuthal extent up to ten scale heights. Maxwell and Reynolds stresses are found to increase by…Anders Johansen, Andrew Youdin, Hubert Klahr·Nov 24, 2008SaveLearn