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Observatory Detects Extragalactic Cosmic Rays Hitting The Earth（图）
Observatory Detects Extragalactic Cosmic Rays Hitting Earth
2017/10/24
Fifty years ago, scientists discovered that the Earth is occasionally hit by cosmic rays of enormous energies. Since then, they have argued about the source of those ultra-high-energy cosmic rays—whet...
Study Confirms Cosmic Rays Have Extragalactic Origins（图）
Cosmic Rays Extragalactic Origins
2017/10/24
In an article to be published Sept. 22 in the journal Science, a group of more than 400 scientists from 18 nations describe how they detected an anisotropy, an asymmetry in the cosmic particles’ distr...
The NAture of the Faint Far-Infrared Extragalactic Source Population: Optical/NIR and Radio Follow-Up Observationts of ISOPHOT Deep-Field Sources using the Keck, Subaru, and VLA Telescopes.
Keck Subaru
2014/12/26
In order to search for obscured objects at high redshifts, we have made deep far-infrared (FIR) deep survey in the Lockman Hole using ISOPHOT onboard ISO (Kawara et al. 1998, A&A, 336, L9). In this su...
The AGN fraction of submm-selected galaxies and contributions to the submm/mm-wave extragalactic background light
galaxies contributions
2014/12/22
We present a comparison of the SCUBA half degree extragalactic survey (SHADES) at 450 μm, 850 μm and 1100 μm with deep guaranteed time 15 μm AKARI FU-HYU survey data and Spitzer guaranteed time data a...
LINEAR POLARIZATION AND TOTAL FLUX DENSITY OF SILICON MONOXIDE MASERS AND ACTIVE EXTRAGALACTIC OBJECTS AT MILLIMETER WAVELENGTHS
Millimeter-wave wireless resources Linear polarization Radio astronomy observatory telescope Maser The Milky Way
2014/12/10
In order to investigate the linear polarization properties of millimeter-wave radio sources, a polarimeter was constructed for use on the Five College Radio Astronomy Observatory 14m telescope. Linear...
Filling the gap in the extragalactic census: A study at 21 cm and in the near -infrared
Galaxy The universe Optical detection The surface brightness system The Milky Way
2014/12/9
Fundamental to a complete understanding of galaxy properties, formation, and evolution is a thorough knowledge of the local galaxy population. Until we understand the nearest, most easily detectable g...
The contribution from blazar cascade emission to the extragalactic gamma-ray background: What a role does the extragalactic magnetic field play?
diffuse radiation galaxies active gamma rays general
2012/2/21
We estimate the contribution to the extragalactic gamma-ray background (EGRB) from both intrinsic and cascade emissions produced by blazars using a simple semi- analysis method for two models of the b...
Multi-wavelength extragalactic surveys and the role of MeerKAT and SALT
Multi-wavelength extragalactic surveys role MeerKAT SALT
2011/10/21
In these proceedings I discuss a range of surveys that are currently underway at optical, near-infrared and far-infrared wavelengths that have large components accessible to both the Southern African ...
Extragalactic Background Light and Gamma-Ray Attenuation
Luminosity density, galaxy spectral energy evolution, extragalactic background light, semi-analytic models of the evolving galaxy population, gamma ray attenuation
2011/10/8
Data from (non-) attenuation of gamma rays from active galactic nuclei (AGN) and gamma ray bursts (GRBs) give upper limits on the extragalactic background light (EBL) from the UV to the mid-IR that ar...
The First Fluorine Abundance Determinations in Extragalactic AGB Carbon Stars
FluorineAbundance Determinations Extragalactic
2011/9/29
Fluorine (19F) abundances (or upper limits) are derived in six extragalactic AGB carbon stars from the HF(1-0) R9 line at 2.3358 mu in high resolution spectra. The stars belong to the Local Group gala...
VERITAS Observations of the Unusual Extragalactic Transient Swift J164449.3+573451
VERITAS Observations Unusual Extragalactic Transient Swift
2011/9/30
We report on very-high-energy ($>$100 GeV) gamma-ray observations of Swift J164449.3+573451, an unusual transient object first detected by the {\it Swift} Observatory and later detected by multiple ra...
The Australia Telescope 20GHz (AT20G) Survey: analysis of the extragalactic source sample
The Australia Telescope 20GHz (AT20G) Survey the extragalactic source sample
2011/1/13
The Australia Telescope 20 GHz (AT20G) survey is a blind survey of the whole Southern sky at 20 GHz with follow-up observations at 4.8, 8.6, and 20 GHz carried out with the Australia Telescope Compact...
Dense molecular gas toward W49A: A template for extragalactic starbursts?
Dense molecular gas toward W49A extragalactic starbursts
2011/1/10
The HCN, HCO+, and HNC molecules are commonly used as tracers of dense star-forming gas in external galaxies, but such observations are spatially unresolved. Reliably inferring the properties of galac...
Deuterated species in extragalactic star-forming regions
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2011/1/5
We present a theoretical study of the deuterated species detectability in various types of extragalactic star-forming regions based on our predictions of chemical abundances. This work is motivated by...
The Cosmological Evolution of Blazars and the Extragalactic Gamma-Ray Background in the Fermi Era
Cosmological Evolution Blazars Extragalactic Gamma-Ray Background
2010/3/8
The latest determination of the extragalactic gamma-ray background (EGRB) radiation by Fermi is compared with the theoretical prediction of the blazar component by Inoue & Totani (2009; hereafter IT09...