中文
相关论文

相关论文: Decametric AGNs: FIRST and NVSS maps and radio spe…

200 篇论文

We have used the Very Large Array to search for compact milliarcsecond-size radio sources near methanol masers in high-mass star-forming regions. Such sources are required for Very Long Baseline Interferometry phase-referencing…

天体物理学 · 物理学 2009-11-11 Y. Xu , M. J. Reid , K. M. Menten , X. W. Zheng

We cross-identified the ROSAT Bright Source Catalog (RBSC) and the NRAO VLA Sky Survey (NVSS) to construct the RBSC-NVSS sample of the brightest X-ray sources (>= 0.1 counts/s or ~1E-12 ergs/cm/cm/s in the 0.1-2.4 keV band) that are also…

天体物理学 · 物理学 2009-10-31 F. E. Bauer , J. J. Condon , T. X. Thuan , J. J. Broderick

The Combined NVSS-FIRST Galaxy (CoNFIG) survey was defined by selecting all sources with S_1.4GHz > 1.3Jy from the NRAO VLA Sky Survey (NVSS) in the north field of the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey. We carried…

天体物理学 · 物理学 2009-04-14 Melanie A. Gendre , Jasper V. Wall

Ultra-steep spectrum (USS) radio sources are good tracers of powerful radio galaxies at $z > 2$. Identification of even a single bright radio galaxy at $z > 6$ can be used to detect redshifted 21cm absorption due to neutral hydrogen in the…

About one third of the gamma-ray sources listed in the second Fermi LAT catalog (2FGL) have no firmly established counterpart at lower energies so being classified as unidentified gamma-ray sources (UGSs). Here we propose a new approach to…

高能天体物理现象 · 物理学 2015-06-16 F. Massaro , R. D'Abrusco , M. Giroletti , A. Paggi , N. Masetti , G. Tosti , M. Nori , S. Funk

In this paper we cross-correlate the FIRST 1.4GHz radio survey with a wide field (~ 1.6deg^2) shallow [f(0.5-8keV) ~ 1e-14erg/s/cm^2] XMM-Newton survey. We find 12 X-ray/radio matches representing 4% of the X-ray selected sample. Most of…

天体物理学 · 物理学 2009-11-10 A. Georgakakis , I. Georgantopoulos , I. Leonidaki , Akylas , G. C. Stewart , C. Goudis

We have assembled an 8.4 GHz survey of bright, flat-spectrum (alpha > -0.5) radio sources with nearly uniform extragalactic (|b|>10 deg) coverage for sources brighter than S_{4.8 GHz} = 65 mJy. The catalog is assembled from existing…

We present the first full release of a survey of the 150 MHz radio sky, observed with the Giant Metrewave Radio Telescope between April 2010 and March 2012 as part of the TGSS project. Aimed at producing a reliable compact source survey,…

宇宙学与河外天体物理 · 物理学 2017-02-08 H. T. Intema , P. Jagannathan , K. P. Mooley , D. A. Frail

This is the first of a series of papers based on sensitive 610 MHz observations of the ELAIS N1 field using the Giant Metrewave Radio Telescope. We describe the observations, processing and source catalogue extraction from a deep image with…

星系天体物理 · 物理学 2019-11-06 E. F. Ocran , A. R. Taylor , M. Vaccari , C. H. Ishwara-Chandra , I. Prandoni

The faint radio-source population includes sources dominated both by star formation and active galactic nuclei (AGN), encoding the evolution of activity in the Universe. To investigate its nature, we probabilistically classified 4,471 radio…

We present a method for identifying radio stellar sources using their proper-motion. We demonstrate this method using the FIRST, VLASS, RACS-low and RACS-mid radio surveys, and astrometric information from Gaia Data Release 3. We find eight…

太阳与恒星天体物理 · 物理学 2023-08-16 Laura Nicole Driessen , George Heald , Stefan W. Duchesne , Tara Murphy , Emil Lenc , James K. Leung , Vanessa A. Moss

Understanding the spectral properties of sources is crucial for the characterization of the radio source population. In this work, we have extensively studied the ELAIS N1 field using various low-frequency radio observations. For the first…

星系天体物理 · 物理学 2023-08-11 Akriti Sinha , Sarvesh Mangla , Abhirup Datta

We investigate the clustering properties of radio sources in the Alternative Data Release 1 of the TIFR GMRT Sky Survey (TGSS), focusing on large angular scales, where previous analyses have detected a large clustering signal. After…

宇宙学与河外天体物理 · 物理学 2019-03-27 A. Dolfi , E. Branchini , M. Bilicki , A. Balaguera-Antolínez , I. Prandoni , R. Pandit

The FIRST survey, begun over twenty years ago, provides the definitive high-resolution map of the radio sky. This VLA survey reaches a 20cm detection sensitivity of 1 mJy over 10,575 deg**2 largely coincident with the SDSS area. Images and…

星系天体物理 · 物理学 2015-06-23 David J. Helfand , Richard L. White , Robert H. Becker

We describe an image-based method that uses two radio criteria, compactness and spectral index, to identify promising pulsar candidates among Fermi Large Area Telescope (LAT) unassociated sources. These criteria are applied to those radio…

Cheung identified a sample of 100 candidate X-shaped radio galaxies using the NRAO FIRST survey; these are small-axial-ratio extended radio sources with off-axis emission. Here we present radio images of 52 of these sources that have been…

星系天体物理 · 物理学 2015-09-16 David H. Roberts , Jake P. Cohen , Jing Lu , Lakshmi Saripalli , Ravi Subrahmanyan

We have cross-matched the 1.4 GHz NRAO VLA Sky Survey (NVSS) with the first 210 fields observed in the 2dF Galaxy Redshift Survey (2dFGRS), covering an effective area of 325 square degrees (about 20% of the final 2dFGRS area). This yields a…

VLA maps obtained at 1.4 GHz with a resolution of 2\farcs5$\times$2\arcsec for three sources and 6\farcs5$\times$2\farcs3 for two sources detected in the RATAN-600 Zenith survey of 1988 have been analyzed. All five objects have an extended…

天体物理学 · 物理学 2007-05-23 Yu. N. Parijskij , W. M. Goss , O. V. Verkhodanov , A. I. Kopylov , N. S. Soboleva , A. V. Temirova

A new list of physical characteristics of 3914 astrometric radio sources, including all 717 ICRF-Ext.2 sources, observed during IVS and NRAO VCS sessions have been compiled. The list includes source type, redshift and visual magnitude (if…

宇宙学与河外天体物理 · 物理学 2016-09-06 Zinovy Malkin , Oleg Titov

In this paper we present near-infrared K-band imaging of a sample of ultra-steep spectrum (USS) radio sources selected at 74 MHz. The dual selection criteria of low frequency and USS means that we should be sensitive to the highest redshift…

天体物理学 · 物理学 2009-11-10 Matt J. Jarvis , Maria J. Cruz , Aaron S. Cohen , Huub J. A. Rottgering , Namir E. Kassim