An Investigation on the Morphological Evolution of Bright-Rimmed CloudsA new Radiative Driven Implosion (RDI) model based on Smoothed Particle Hydrodynamics (SPH) technique is developed and applied to investigate the morphological evolutions of molecular clouds under…J. Miao, G. J. White, M. A. Thompson et al.·Oct 15, 2008SaveLearn
Where have all the bulges gone?Several recent studies indicate that bulges are more complex than merely structureless relaxed stellar systems. We study the HST images of a sample of 130 nearby early type (S0-Sab) disc galaxies and…Leonel Gutierrez, Antti Tamm, John Beckman et al.·Oct 15, 2008SaveLearn
Beryllium abundances in metal-poor starsWe have determined beryllium abundances for 25 metal-poor stars based on the high resolution and high signal-to-noise ratio spectra from the VLT/UVES database. Our results confirm that Be abundances…K. F. Tan, J. R. Shi, G. Zhao·Oct 15, 2008SaveLearn
Silicon carbide absorption features: dust formation in the outflows of extreme carbon starsInfrared carbon stars without visible counterparts are generally known as extreme carbon stars. We have selected a subset of these stars with absorption features in the 10-13 μm range, which has…Angela K. Speck, Adrian B. Corman, Kristina Wakeman et al.·Oct 15, 2008SaveLearn
Neutrinos and Future Concordance CosmologiesWe review the free parameters in the concordance cosmology, and those which might be added to this set as the quality of astrophysical data improves. Most concordance parameters encode information…Peter Adshead, Richard Easther·Oct 15, 2008SaveLearn
Thermal Effects of Circumplanetary Disk Formation around Proto-Gas Giant PlanetsThe formation of a circumplanetary disk and accretion of angular momentum onto a protoplanetary system are investigated using 3D hydrodynamical simulations. The local region around a protoplanet in a…Masahiro N. Machida·Oct 15, 2008SaveLearn
The Star Formation Efficiency in Nearby Galaxies: Measuring Where Gas Forms Stars EffectivelyWe measure the star formation efficiency (SFE), the star formation rate per unit gas, in 23 nearby galaxies and compare it to expectations from proposed star formation laws and thresholds. We use HI…Adam K. Leroy, Fabian Walter, Elias Brinks et al.·Oct 15, 2008SaveLearn
On the origin of microturbulence in hot starsWe present results from the first extensive study of convection zones in the envelopes of hot massive stars, which are caused by opacity peaks associated with iron and helium ionization. These…M. Cantiello, N. Langer, I. Brott et al.·Oct 15, 2008SaveLearn
LCDM predictions for galaxy protoclusters I: the relation between galaxies, protoclusters and quasars at z~6Motivated by recent observational studies of the environment of z~6 QSOs, we have used the Millennium Run (MR) simulations to construct a very large (~20 deg2) mock redshift survey of star-forming…Roderik Overzier, Qi Guo, Guinevere Kauffmann et al.·Oct 14, 2008SaveLearn
Comment on the Black Hole Recoil Candidate Quasar SDSS J092712.65+294344.0SDSS J092712.65+294344.0 has been proposed as a candidate for a supermassive black hole (~108.8 solar masses) ejected at high speed from the host galactic nucleus by gravitational radiation recoil,…G. A. Shields, E. W. Bonning, S. Salviander·Oct 14, 2008SaveLearn
Monte Carlo Markov Chain Parameter Estimation in Semi-Analytic Models of Galaxy Formation[abridged] We present a statistical exploration of the parameter space of the De Lucia and Blaizot version of the Munich semi-analytic model built upon the millennium dark matter simulation. This is…Bruno Henriques, Peter Thomas, Seb Oliver et al.·Oct 14, 2008SaveLearn
The Different Evolution of Gas and Dust in Disks around Sun-like and Cool StarsWe present the first comprehensive, comparative Spitzer/IRS study of the dust and gas properties of disks around young sun-like stars (K1-M5) and cool stars/brown dwarfs (M5-M9). The comparison of…I. Pascucci, D. Apai, K. Luhman et al.·Oct 14, 2008SaveLearn
Neutron-Rich Freeze-Out in Viscously Spreading Accretion Disks Formed from Compact Object MergersAccretion disks with masses ~0.001-0.1 Msun form during the merger of neutron star (NS)-NS and black hole-NS binaries. Initially, such hyper-accreting disks cool efficiently by neutrino emission and…B. D. Metzger, A. L. Piro, E. Quataert·Oct 14, 2008SaveLearn
Obscured and powerful AGN and starburst activities at z~3.5We report the discovery of two sources at z=3.867 and z=3.427 that exhibit powerful starburst and AGN activities. They benefit from data from radio to X rays from the CFHTLS-D1/SWIRE/XMDS surveys.…M. Polletta, A. Omont, S. Berta et al.·Oct 14, 2008SaveLearn
Turbulent dynamos with shear and fractional helicityDynamo action owing to helically forced turbulence and large-scale shear is studied using direct numerical simulations. The resulting magnetic field displays propagating wave-like behavior. This…P. J. Käpylä, A. Brandenburg·Oct 14, 2008SaveLearn
HINODE Observations of Chromospheric Brightenings in the Ca II H Line during small-scale Flux Emergence EventsCa2 H emission is a well-known indicator of magnetic activity in the Sun and other stars. It is also viewed as an important signature of chromospheric heating. However, the Ca2 H line…S. L. Guglielmino, F. Zuccarello, P. Romano et al.·Oct 14, 2008SaveLearn
Generation of Circular Polarization of the Cosmic Microwave BackgroundThe standard cosmological model, which includes only Compton scattering photon interactions at energy scales near recombination, results in zero primordial circular polarization of the cosmic…Stephon Alexander, Joseph Ochoa, Arthur Kosowsky·Oct 14, 2008SaveLearn
Rotational Mixing in Magellanic Clouds B Stars - Theory versus ObservationWe have used VLT FLAMES data to constrain the uncertain physics of rotational mixing in stellar evolution models. We have simulated a population of single stars and find two groups of observed stars…I. Brott, I. Hunter, A. de Koter et al.·Oct 14, 2008SaveLearn
Stellar tracers of the Cygnus Arm. II: A young open cluster in Cam OB3Cam OB3 is the only defined OB association believed to belong to the Outer Galactic Arm or Cygnus Arm. Very few members have been observed and the distance modulus to the association is not well…Ignacio Negueruela, Amparo Marco·Oct 14, 2008SaveLearn
Multiple stellar populations in Magellanic Clouds clusters. I. An ordinary feature for intermediate age globulars in the LMC?The discovery of multiple MSs in NGC2808 and Omega Centauri, and multiple SGBs in NGC1851 and NGC6388 has challenged the long-held paradigm that GCs consist of simple stellar populations. This…A. P. Milone, L. R. Bedin, G. Piotto et al.·Oct 14, 2008SaveLearn
The ACS Nearby Galaxy Survey Treasury I. The Star Formation History of the M81 Outer DiskThe ACS Nearby Galaxy Survey Treasury (ANGST) is a large Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) treasury program to obtain resolved stellar photometry for a volume-limited…Benjamin F. Williams, Julianne J. Dalcanton, Anil C. Seth et al.·Oct 14, 2008SaveLearn
Synchrotron Emissions in GRB Prompt Phase Using a Semi Leptonic and Hadronic ModelIn this communication devoted to the prompt emission of GRBs, we claim that some important parameters associated to the magnetic field, such as its index profile, the index of its turbulence spectrum…S. Guiriec, D. Gialis, G. Pelletier et al.·Oct 14, 2008SaveLearn
New Complexities in the Low-State line profiles of AM HerculisWhen accretion temporarily ceases in the polar AM Her, the emission line profiles are known to develop several distinct components, whose origin remains poorly understood. The new low-state spectra…S. Kafka, T. Ribeiro, R. Baptista et al.·Oct 14, 2008SaveLearn
High Spatial Resolution Galactic 3D Extinction Mapping with IPHASWe present an algorithm ( mead, for `Mapping Extinction Against Distance') which will determine intrinsic (r' - i') colour, extinction, and distance for early-A to K4 stars…S. E. Sale, J. E. Drew, Y. C. Unruh et al.·Oct 14, 2008SaveLearn
Probing the accretion disk and central engine structure of NGC4258 with Suzaku and XMM-Newton observations[abridged] We present an X-ray study of the low-luminosity active galactic nucleus (AGN) in NGC4258 using data from Suzaku, XMM-Newton, and the Swift/BAT survey. We find that signatures of X-ray…Christopher S. Reynolds, Michael A. Nowak, Sera Markoff et al.·Oct 14, 2008SaveLearn