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19922026
Showing 2008Show all

621 papers · 1 filter

astro-ph.HE2008

Gamma-ray Bursts: Light on the distant Universe

Jonathan Grindlay

Observations of a long-lasting Gamma-ray burst, one that has the brightest optical counterpart yet discovered, challenge theoretical understanding of these bursts but may enhance t…

astro-ph2008★ 34 cited

FIRST "Winged" and X-shaped Radio Source Candidates: II. New Redshifts

C. C. Cheung, Stephen E. Healey, Hermine Landt +2

We 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 F…

astro-ph2008★ 2 cited

Stellar Ages from Stellar Rotation

Soren Meibom

Our ability to determine stellar ages from measurements of stellar rotation, hinges on how well we can measure the dependence of rotation on age for stars of different masses. Rota…

astro-ph2008★ 9 cited

Infall and rotation motions in the HH 111 protostellar system: A flattened envelope in transition to a disk?

Chin-Fei Lee, Yao-Yuan Mao, Bo Reipurth

We have mapped the central region of the HH 111 protostellar system in 1.33 mm continuum, C18O(J=2-1), 13CO (J=2-1), and SO (N_J=5_6-4_5) emission at ~3" resolution with the Submil…

astro-ph2008★ 7 cited

Search for Primordial Black Holes with SGARFACE

M. Schroedter, F. Krennrich, S. LeBohec +7

The Short GAmma Ray Front Air Cherenkov Experiment (SGARFACE) uses the Whipple 10 m telescope to search for bursts of rays. SGARFACE is sensitive to bursts with duration from a…

astro-ph2008★ 70 cited

Large grains in disks around young stars: ATCA observations of WW Cha, RU Lup, and CS Cha

Dave Lommen, Sarah Maddison, Chris Wright +3

Grains in disks around young stars grow from interstellar submicron sizes to planetesimals over the course of several Myr. Thermal emission of large grains or pebbles can be best o…

astro-ph2008★ 69 cited

The solar wind charge-transfer X-ray emission in the 1/4 keV energy range: inferences on Local Bubble hot gas at low Z

D. Koutroumpa, R. Lallement, J. C. Raymond +1

We present calculations of the heliospheric SWCX emission spectra and their contributions in the ROSAT 1/4 keV band. We compare our results with the soft X-ray diffuse background (…

astro-ph2008★ 64 cited

Cosmological Perturbations at Second Order and Recombination Perturbed

Leonardo Senatore, Svetlin Tassev, Matias Zaldarriaga

We derive the full set of second-order equations governing the evolution of cosmological perturbations, including the effects of the first-order electron number density perturbatio…

astro-ph2008★ 68 cited

Evolution of Magnetic Fields in High Mass Star Formation: SMA dust polarization image of the UCHII region G5.89-0.39

Ya-Wen Tang, Paul T. P. Ho, Josep Miquel Girart +3

We report high angular resolution (3") Submillimeter Array (SMA) observations of the molecular cloud associated with the Ultra-Compact HII region G5.89-0.39. Imaged dust continuum…

astro-ph2008★ 110 cited

The Environments of Active Galactic Nuclei within the zCOSMOS Density Field

J. D. Silverman, K. Kovac, C. Knobel +58

The impact of environment on AGN activity up to z~1 is assessed by utilizing a mass-selected sample of galaxies from the 10k catalog of the zCOSMOS spectroscopic redshift survey. W…

astro-ph2008★ 41 cited

The formation of the black hole in the X-ray binary system V404 Cyg

J. C. A. Miller-Jones, P. G. Jonker, G. Nelemans +5

Using new and archival radio data, we have measured the proper motion of the black hole X-ray binary V404 Cyg to be 9.2+/-0.3 mas/yr. Combined with the systemic radial velocity fro…

quant-ph2008★ 48 cited

Efficient formation of ground state ultracold molecules via STIRAP from the continuum at a Feshbach resonance

Elena Kuznetsova, Susanne F. Yelin, Marko Gacesa +2

We develop a complete theoretical description of photoassociative Stimulated Raman Adiabatic Passage (STIRAP) near a Feshbach resonance in a thermal atomic gas. We show that it is…

astro-ph2008★ 14 cited

Phase resolved spectroscopy of the accreting millisecond X-ray pulsar SAX J1808.4-3658 during the 2008 outburst

R. Cornelisse, P. D'Avanzo, T. Munoz-Darias +6

aims: We obtained phase-resolved spectroscopy of the accreting millisecond X-ray pulsar SAX J1808.4-3658 during its outburst in 2008 to find a signature of the donor star, constrai…

astro-ph2008★ 12 cited

Chandra observations of the galaxy group AWM 5: cool core re-heating and thermal conduction suppression

A. Baldi, W. Forman, C. Jones +4

We present an analysis of a 40 ksec Chandra observation of the galaxy group AWM 5. It has a small ( kpc) dense cool core with a temperature of keV and the temperat…

astro-ph2008★ 145 cited

A Characteristic Division Between the Fueling of Quasars and Seyferts: Five Simple Tests

Philip F. Hopkins, Lars Hernquist

Given the existence of the M_BH-sigma relation, models of self-regulated black hole (BH) growth require both a fuel supply and growth of the host bulge to deepen the potential, or…

astro-ph2008★ 10 cited

Detection of the second eclipsing high mass X-ray binary in M 33

W. Pietsch, F. Haberl, T. J. Gaetz +7

Chandra data of the X-ray source [PMH2004] 47 were obtained in the ACIS Survey of M 33 (ChASeM33) in 2006. During one of the observations, the source varied from a high state to a…

astro-ph2008★ 1k cited

Chandra Cluster Cosmology Project III: Cosmological Parameter Constraints

A. Vikhlinin, A. V. Kravtsov, R. A. Burenin +8

Chandra observations of large samples of galaxy clusters detected in X-rays by ROSAT provide a new, robust determination of the cluster mass functions at low and high redshifts. St…

astro-ph2008★ 44 cited

Shock Speed, Cosmic Ray Pressure, and Gas Temperature in the Cygnus Loop

Greg Salvesen, John C. Raymond, Richard J. Edgar

Upper limits on the shock speeds in supernova remnants can be combined with post-shock temperatures to obtain upper limits on the ratio of cosmic ray to gas pressure (P_CR / P_G) b…

astro-ph2008★ 48 cited

A Millimetre Survey of Starburst Dominated Ultraluminous Infrared Galaxies at z~2

J. D. Younger, A. Omont, N. Fiolet +6

We present millimetre observations of a sample of 12 high redshift ultraluminous infrared galaxies (ULIRGs) in the Extended Growth Strip (EGS). These objects were initially selecte…

astro-ph2008★ 52 cited

A spatially resolved study of photoelectric heating and [CII] cooling in the LMC

D. Rubin, S. Hony, S. C. Madden +20

(abridged) We study photoelectric heating throughout the Large Magellanic Cloud. We quantify the importance of the [CII] cooling line and the photoelectric heating process of vario…

hep-th2008★ 59 cited

The Volume of the Universe after Inflation and de Sitter Entropy

Sergei Dubovsky, Leonardo Senatore, Giovanni Villadoro

We calculate the probability distribution for the volume of the Universe after slow-roll inflation both in the eternal and in the non-eternal regime. Far from the eternal regime th…

astro-ph2008★ 26 cited

Binarity and multiperiodicity in high-amplitude delta Scuti stars

A. Derekas, L. L. Kiss, T. R. Bedding +10

We have carried out a photometric and spectroscopic survey of bright high-amplitude delta Scuti (HADS) stars. The aim was to detect binarity and multiperiodicity (or both) in order…

astro-ph2008★ 13 cited

Oscillations of the Inner Regions of Viscous Accretion Disks

Chi-kwan Chan

Although quasi-periodic oscillations (QPOs) have been discovered in different X-ray sources, their origin is still a matter of debate. Analytical studies of hydrodynamic accretion…

astro-ph2008★ 20 cited

A HST/WFPC2 survey of bright young clusters in M31. I. VdB0, a massive star cluster seen at ~= 25 Myr

S. Perina, P. Barmby, M. A. Beasley +12

{Aims.} We introduce our imaging survey of possible young massive globular clusters in M31 performed with the Wide Field and Planetary Camera 2 (WFPC2) on the Hubble Space Telescop…