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X-ray scaling relations of galaxy groups in a hydrodynamic cosmological simulation
theory clusters
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2014/12/26
We examine the scalings of X-ray luminosity, temperature, and dark matter or galaxy velocity dispersion for galaxy groups in a ΛCDM cosmological simulation, which incorporates gravity, gas dynamics, r...
Lyman Alpha Absorber Correlations and the Bias of the Lyman Alpha Forest
BIAS THE Lyman Alpha Forest
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2014/12/26
Lyman alpha absorber correlations contain information about the underlying density distribution associated with a particular class of absorbers. As such, they provide an opportunity to independently m...
Toward a precise measurement of matter clustering: Ly alpha forest data at redshifts 2-4
absorption lines large scale structure of universe
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2014/12/26
We measure the filling factor, correlation function, and power spectrum of transmitted flux in a large sample of Lyα forest spectra, comprised of 30 Keck HIRES spectra and 23 Keck LRIS spectra. We inf...
An upper limit to the age of the galactic bar
carbon disk
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2014/12/26
Using data from the Two Micron All Sky Survey, we identify a population of infrared carbon stars with J-KS ≥ 2 in the Milky Way. These stars are shown to trace the stellar bar previously identified in...
We use hydrodynamic simulations to examine how the baryonic components of galaxies are assembled, focusing on the relative importance of mergers and smooth accretion in the formation of ~L* systems. I...
A Critical Examination of Hypernova Remnant Candidates in M101. II. NGC 5471B
M101 kinematics and dynamics
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2014/12/26
NGC 5471B has been suggested to contain a hypernova because of its extraordinarily bright X-ray emission. To assess its true nature, we have obtained high-resolution images in continuum bands and nebu...
High-Resolution Imaging of Molecular Line Emission from High-Redshift QSOs
starburst evolution radio lines
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2014/12/26
We present moderate- (1'') and high-resolution (02) observations of the CO (2–1) emission at 43 GHz and radio continuum emission at 1.47 GHz from the z = 4.7 QSO BRI 1202-0725 and the z = 4.4 QSO BRI ...
Discovery of a 136 Millisecond Radio and X-Ray Pulsar in Supernova Remnant G54.1+0.3
G54.1+0.3 PSR J1930+1852
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2014/12/26
We report the discovery of a pulsar with period P = 136 ms and dispersion measure 308 cm-3 pc in a deep observation of the supernova remnant (SNR) G54.1+0.3 with the Arecibo radio telescope. Timing me...
Sensitive limits on the water abundance in cold low-mass molecular cores
formation submil
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2014/12/26
We present Submillimeter Wave Astronomy Satellite observations of water vapor in two cold starless clouds, B68 and core D in ρ Ophiuchi. Sensitive nondetections of the 110-101 transition of o-H2O are ...
Investigating the long-term evolution of galaxies: Noise, cuspy halos and bars
cuspy halos bars
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2014/12/26
I review the arguments for the importance of halo structure in driving galaxy evolution and coupling a galaxy to its environment. We begin with a general discussion of the key dynamics and examples of...
We review recent developments in the theory of the Ly forest and their implications for the role of the forest as a test of cosmological models. Simulations predict a relatively tight correlation betw...
The Canada-UK Deep Submillimeter Survey. VI. The 3 hour field
high-redshift submillimeter
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2014/12/26
We present the complete submillimeter data for the Canada-UK Deep Submillimeter Survey (CUDSS) 3h field. The observations were taken with the Submillimeter Common-User Bolometric Array (SCUBA) on the ...
The Canada-UK deep submillimeter survey. VII. Optical and near-infrared identifications for the 14 hour field
formation galaxies:high-redshift
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2014/12/26
We present the multiwavelength identifications for 23 sources in the Canada-UK Deep Submillimeter Survey (CUDSS) 14h field. The identifications have been selected on the basis of radio and near-infrar...
Chandra Observation of the Edge-on Galaxy NGC 3556 (M108): Violent Galactic Disk-Halo Interaction Revealed
NGC 3556 spiral
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2014/12/26
We present a 60 ks Chandra ACIS-S observation of the isolated edge-on spiral galaxy NGC 3556, together with a multiwavelength analysis of various discrete X-ray sources and diffuse X-ray features. Amo...
The Origin of the Dust Arch in the Halo of NGC 4631: An Expanding Superbubble?
NGC 4631 galaxies
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2014/12/24
We study the nature and the origin of the dust arch in the halo of the edge-on galaxy NGC 4631 detected by Neininger & Dumke. We present CO observations made using the new on-the-fly mapping mode with...