Chandra astrometry sets a tight upper limit to the proper motion of SGR 1900+14The soft gamma-ray repeater (SGR) SGR 1900+14 lies a few arcminutes outside the edge of the shell supernova remnant (SNR) G42.8+0.6. A physical association between the two systems has been proposed -…A. De Luca, P. A. Caraveo, P. Esposito et al.·Oct 21, 2008SaveLearn
The X-Ray Point-Source Population of NGC 1365: The Puzzle of Two Highly-Variable Ultraluminous X-ray SourcesWe present 26 point-sources discovered with Chandra within 200" (~20kpc) of the center of the barred supergiant galaxy NGC 1365. The majority of these sources are high-mass X-ray binaries,…Iskra V. Strateva, Stefanie Komossa·Oct 21, 2008SaveLearn
Simultaneous X-ray/optical/UV snapshots of active galactic nuclei from XMM-Newton: spectral energy distributions for the reverberation mapped sampleWe employ contemporaneous optical, UV and X-ray observations from the XMM-Newton EPIC-pn and Optical Monitor (OM) archives to present, for the first time, simultaneous spectral energy distributions…R. V. Vasudevan, A. C. Fabian·Oct 21, 2008SaveLearn
The efficient low-mass Seyfert MCG-05-23-016The Seyfert 1.9 galaxy MCG-05-23-016 has been shown to exhibit a complex X-ray spectrum. This source has moderate X-ray luminosity, hosts a comparably low-mass black hole, but accretes at a high…V. Beckmann, T. J. -L. Courvoisier, N. Gehrels et al.·Oct 21, 2008SaveLearn
Non-thermal emissions from outer magnetospheric accelerators of middle-aged pulsarsWe discuss γ-ray emissions from the outer gap accelerators of middle-aged pulsars for part of the series of our studies. A two-dimensional electrodynamic model is used to solve the distribution of…J. Takata, H. -K. Chang·Oct 21, 2008SaveLearn
NIR/Optical Counterparts of Hotspots in Radio GalaxiesWe present new high spatial resolution VLT and VLA observations of a sample of nine low-power (P1.4 GHz < 1025 W/Hz) radio hotspots. Infrared/optical emission is definitely detected in four of…K. -H. Mack, M. A. Prieto, G. Brunetti et al.·Oct 21, 2008SaveLearn
Multi-Tev Gamma-Ray Observation from the Crab Nebula Using the Tibet-III Air Shower Array Finely Tuned by the Cosmic-Ray Moon's ShadowThe Tibet-III air shower array, consisting of 533 scintillation detectors, has been operating successfully at Yangbajing in Tibet, China since 1999. Using the dataset collected by this array from…M. Amenomori·Oct 21, 2008SaveLearn
Oscillation and Future Detection of Failed Supernova Neutrinos from Black Hole Forming CollapseRecently, stellar collapse involving black hole formation from massive stars is suggested to emit enormous fluxes of neutrinos on par with ordinary core-collapse supernovae. We investigate their…Ken'ichiro Nakazato, Kohsuke Sumiyoshi, Hideyuki Suzuki et al.·Oct 21, 2008SaveLearn
Fossil remnants of reionization in the halo of the Milky WayOur recently completed one billion particle Via Lactea II simulation of a Milky Way-sized dark matter halo resolves over 50,000 gravitationally bound clumps orbiting today within the virialized…P. Madau, M. Kuhlen, J. Diemand et al.·Oct 21, 2008SaveLearn
Cosmography with Galaxy ClustersIn the present work we focus on future experiments using cluster abundance observations to constraint the Dark Energy equation of state parameter, w. To obtain tight constraints from this kind of…M. Soares-Santos, R. R. de Carvalho, F. La Barbera et al.·Oct 21, 2008SaveLearn
The Molecular Properties of Galactic HII RegionsWe derive the molecular properties for a sample of 301 Galactic HII regions including 123 ultra compact (UC), 105 compact, and 73 diffuse nebulae. We analyze all sources within the BU-FCRAO Galactic…L. D. Anderson, T. M. Bania, J. M. Jackson et al.·Oct 21, 2008SaveLearn
Globular Cluster Systems in Nearby Dwarf Galaxies: I. HST/ACS Observations and Dynamical Properties of Globular Clusters at Low Environmental DensityWe investigate the old globular cluster (GC) population of 68 faint (Mv>-16 mag) dwarf galaxies located in the halo regions of nearby (<12 Mpc) loose galaxy groups and in the field environment based…Iskren Y. Georgiev, Thomas H. Puzia, Michael Hilker et al.·Oct 21, 2008SaveLearn
Neutrino Oscillation Measurements with IceCubeWe present preliminary results for a neutrino oscillation analysis in progress on data collected with the IceCube 22-string detector during 2007 and 2008. The goal of this analysis is to measure muon…Carsten Rott·Oct 20, 2008SaveLearn
The statistics of accelerations seen in radial velocity searches for planetsRadial velocity searches for extrasolar planets have discovered stars undergoing slow accelerations. The accelerations are likely due to one or more gas giant planets or brown dwarfs orbiting with…Alice C. Quillen·Oct 20, 2008SaveLearn
Gas-dynamic shock heating of post-flare loops due to retraction following localized, impulsive reconnectionWe present a novel model in which shortening of a magnetic flux tube following localized, three-dimensional reconnection generates strong gas-dynamic shocks around its apex. The shortening releases…D. W. Longcope, S. E. Guidoni, M. G. Linton·Oct 20, 2008SaveLearn
Cosmic flow from 2MASS redshift survey: The origin of CMB dipole and implications for LCDM cosmologyWe generate the peculiar velocity field for the 2MASS Redshift Survey (2MRS) catalog using an orbit-reconstruction algorithm. The reconstructed velocities of individual objects in 2MRS are…G. Lavaux, R. Brent Tully, R. Mohayaee et al.·Oct 20, 2008SaveLearn
The CMBR ISW and HI 21-cm Cross-correlation Angular Power SpectrumThe late-time growth of large scale structures (LSS) is imprinted in the CMBR anisotropy through the Integrated Sachs Wolfe (ISW) effect. This is perceived to be a very important observational probe…Tapomoy Guha Sarkar, Kanan K. Datta, Somnath Bharadwaj·Oct 20, 2008SaveLearn
Early Annihilation and Diffuse Backgrounds in 1/v WIMP modelsSeveral recent studies have considered modifications to the standard weakly-interacting massive particle (WIMP) scenario in which the cross section (times relative velocity v) for pair annihilation…Marc Kamionkowski, Stefano Profumo·Oct 20, 2008SaveLearn
Inflationary Potential from 21 cm Tomography and PlanckThree-dimensional neutral hydrogen mapping using the redshifted 21 cm line has recently emerged as a promising cosmological probe. Within the framework of slow-roll reconstruction, we analyze how…Vernon Barger, Yu Gao, Yi Mao et al.·Oct 20, 2008SaveLearn
The Dark Energy Camera (DECam)In this paper we describe the Dark Energy Camera (DECam), which will be the primary instrument used in the Dark Energy Survey. DECam will be a 3 sq. deg. mosaic camera mounted at the prime focus of…K. Honscheid, D. L. DePoy·Oct 20, 2008SaveLearn
The Blazar Sequence and the Cosmic Gamma-Ray Background Radiation in the Fermi Era(Abridged) We present a new model of the blazar gamma-ray luminosity function (GLF) and the spectrum of the extragalactic gamma-ray background (EGRB), which is consistent with the observed…Yoshiyuki Inoue, Tomonori Totani·Oct 20, 2008SaveLearn
Improving the performance of the single-dish Cherenkov telescope MAGIC through the use of signal timingThe Cherenkov light flashes produced by Extensive Air Showers are very short in time. A high bandwidth and fast digitizing readout, therefore, can minimize the influence of the background from the…MAGIC Collaboration·Oct 20, 2008SaveLearn
Eight-Dimensional Mid-Infrared/Optical Bayesian Quasar SelectionWe explore the multidimensional, multiwavelength selection of quasars from mid-IR (MIR) plus optical data, specifically from Spitzer-IRAC and the Sloan Digital Sky Survey (SDSS). We apply modern…Gordon T. Richards, Rajesh P. Deo, Mark Lacy et al.·Oct 20, 2008SaveLearn
The Fermi Gamma Ray Space Telescope discovers the Pulsar in the Young Galactic Supernova-Remnant CTA 1Energetic young pulsars and expanding blast waves (supernova remnants, SNRs) are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi…Fermi LAT Collaboration·Oct 20, 2008SaveLearn
Upper Limits on the VHE gamma-ray Emission from the Willman 1 Satellite Galaxy with the MAGIC telescopeWe present the result of the observation of the ultrafaint dwarf galaxy Willman 1 performed with the 17 m MAGIC telescope during 15.5 hr between March and May 2008. No significant γ-ray emission…MAGIC Collaboration, E. Aliu·Oct 20, 2008SaveLearn