搜索结果: 106-120 共查到“天文学 radio”相关记录193条 . 查询时间(0.105 秒)
The Production of Ultra High Energy Cosmic Rays during the Early Epochs of Radio-loud AGN
High Energy Astrophysical Phenomena (astro-ph.HE)
2011/1/4
Powerful radio-loud active galactic nuclei (AGN) with large Mpc-scale jets have been theoretically motivated as emitters of high-energy cosmic rays. Recent radio observations have established a populo...
Radio Frequency Interference Mitigation at the WSRT
Instrumentation and Methods for Astrophysics (astro-ph.IM)
2011/1/4
The sensitivity of radio astronomical stations is often limited by man-made radio frequency interference (RFI) due to a variety of terrestrial activities. An RFI mitigation subsystem (RFIMS) based on ...
Intermittent activity of radio sources. Accretion instabilities and jet precession
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2011/1/4
We consider the radiation pressure instability operating on short timescales 10^3 - 10^6 years in the accretion disk around a supermassive black hole as the origin of the intermittent activity of radi...
A String of Radio Emission Associated with IRAS 16562-3959: A Collimated Jet Emanating from a Luminous Massive YSO
Solar and Stellar Astrophysics (astro-ph.SR)
2010/12/29
We report the discovery made using the Australia Telescope Compact Array of a remarkable string of radio emission towards IRAS 16562-3959, a luminous infrared source with a bolometric luminosity of $7...
Chandra high resolution spectroscopy of the circumnuclear matter in the Broad Line Radio Galaxy 3C445
High Energy Astrophysical Phenomena (astro-ph.HE)
2010/12/29
We present evidence for X-ray line emitting and absorbing gas in the nucleus of the Broad-Line Radio Galaxy (BLRG), 3C 445. A 200ks Chandra LETG observation of 3C 445 reveals the presence of several h...
Status and Strategies of Current LUNASKA Lunar Cherenkov Observations with the Parkes Radio Telescope
High Energy Astrophysical Phenomena (astro-ph.HE) Instrumentation and Methods for Astrophysics (astro-ph.IM)
2010/12/28
LUNASKA (Lunar UHE Neutrino Astrophysics with the Square Kilometre Array) is an ongoing project conducting lunar Cherenkov observations in order to develop techniques for detecting neutrinos with the ...
A Radio Air-Shower Test Array (RASTA) for IceCube
High Energy Astrophysical Phenomena (astro-ph.HE) Instrumentation and Methods for Astrophysics (astro-ph.IM)
2010/12/28
In this paper we explore the possibility to complement the cosmic ray physics program of the IceCube observatory with an extended surface array of radio antennas.
An optical spectroscopic survey of the 3CR sample of radio galaxies with z<0.3. III. Completing the sample
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/27
We present optical nuclear spectra for nine 3CR radio sources obtained with the Telescopio Nazionale Galileo, that complete our spectroscopic observations of the sample up to redshifts $<$ 0.3. We mea...
The Spitzer High Redshift Radio Galaxy Survey
Cosmology and Extragalactic Astrophysics (astro-ph.CO) Galaxy Astrophysics (astro-ph.GA)
2010/12/27
We present results from a comprehensive imaging survey of 70 radio galaxies at redshifts 1ras onboard the Spitzer Space Telescope. The resulting spectral energy distribution...
A Radio Perspective on the Wet Merger Remnant NGC 34
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/24
We present VLA observations of the neutral hydrogen and radio continuum of NGC 34 (= NGC 17 = Mrk 938). This object is an ideal candidate to study the fate of gas in mergers, since, as shown by an opt...
Very Large Array observations of the 8 o'clock arc lens system: Radio emission and a limit on the star-formation rate
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/23
The 8 o'clock arc is a gravitationally lensed Lyman Break Galaxy (LBG) at redshift z=2.73 that has a star-formation rate (SFR) of 270 solar-mass/year (derived from optical and near-infrared spectrosco...
The transition from quasar radio-loud to radio-quiet state in the framework of the black hole scalability hypothesis
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/23
There are several lines of evidence that active galactic nuclei (AGN) can be regarded as scaled-up X-ray binaries (XRB). The timescales of the evolutionary phenomena in these two classes are proportio...
A deep Chandra observation of the poor cluster AWM4 - II. The role of the radio jets in enriching the intra-cluster medium
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/23
We use a Chandra observation of the poor cluster AWM4 to map the temperature and abundance of the intra-cluster medium, so as to examine the influence of the central radio galaxy on its environment.
Evidence for a maximum jet efficiency for the most powerful radio galaxies
High Energy Astrophysical Phenomena (astro-ph.HE) Cosmology and Extragalactic Astrophysics (astro-ph.CO) Galaxy Astrophysics (astro-ph.GA)
2010/12/24
We use new mid-infrared (mid-IR) photometry from the Spitzer Space Telescope to study the relations between low-frequency radio luminosity density L_151MHz, mid-IR (12um rest-frame) luminosity L_12um,...
A closer view of the radio-FIR correlation: disentangling the contributions of star formation and AGN activity
Galaxy Astrophysics (astro-ph.GA)
2010/12/23
We extend the Unified Radio Catalog, a catalog of sources detected by various (NVSS, FIRST, WENSS, GB6) radio surveys, and SDSS, to IR wavelengths by matching it to the IRAS Point and Faint Source cat...