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相关论文: The VLA Low-frequency Sky Survey

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The Combined EIS-NVSS Survey Of Radio Sources (CENSORS) has been produced with the primary goal of investigating the cosmological evolution of the radio luminosity function. This 1.4GHz sample, complete to the 7.2 mJy level, contains 150…

天体物理学 · 物理学 2017-08-23 M. H. Brookes , P. N. Best

We have observed an area of approximatley 27 deg^2 to an rms noise level of less than 0.2 mJy at 15.7 GHz, using the Arcminute Microkelvin Imager Large Array. These observations constitute the most sensitive radio-source survey of any…

We present the first sub-mJy ($\approx0.7$ mJy beam$^{-1}$) survey to be completed below 100 MHz, which is over an order of magnitude deeper than previously achieved for widefield imaging of any field at these low frequencies. The high…

VLBA observations at 18 cm are presented for 28 Compact Steep-spectrum radio Sources (CSSs) from the B3-VLA CSS sample. These sources were unresolved in previous VLA observations at high frequencies or their brightness distribution was…

天体物理学 · 物理学 2009-11-07 D. Dallacasa , S. Tinti , C. Fanti , R. Fanti , L. Gregorini , C. Stanghellini , M. Vigotti

As a step toward investigating the parsec-scale properties of faint extragalactic radio sources, the Very Long Baseline Array (VLBA) was used at 5.0 GHz to obtain phase-referenced images of 76 sources in the NOAO Bootes field. These 76…

天体物理学 · 物理学 2008-11-26 J. M. Wrobel , G. B. Taylor , T. A. Rector , S. T. Myers , C. D. Fassnacht

Ultra Steep Spectrum (USS) radio sources are one of the efficient tracers of High Redshift Radio Galaxies (HzRGs). To search for HzRGs candidates, we investigate properties of a large sample of faint USS sources derived from our deep 325…

As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216 sq. deg. of the southern sky at 18GHz (16mm) using a novel wide-band (3.4GHz bandwidth) analogue correlator on one baseline of the Australia…

The polarization properties of radio sources at very low frequencies (<200 MHz) have not been widely measured, but the new generation of low-frequency radio telescopes, including the Low Frequency Array (LOFAR: a Square Kilometre Array Low…

Aims. With the recent preliminary release of the LOFAR LBA Sky Survey (LoLSS), the first wide-area, ultra-low frequency observations from LOFAR were published. Our aim is to combine this data set with other surveys at higher frequencies to…

天体物理仪器与方法 · 物理学 2023-06-22 Lukas Böhme , Dominik J. Schwarz , Francesco de Gasperin , Huub J. A. Röttgering , Wendy L. Williams

Aims - We report new Very Large Array polarimetric observations of Compact Steep-Spectrum (CSS) sources at 8.4, 15, and 23GHz. Methods - Using multi-frequency VLA observations we have derived sub-arcsecond resolution images of the total…

宇宙学与河外天体物理 · 物理学 2015-06-15 F. Mantovani , A. Rossetti , W. Junor , D. J. Saikia , C. J. Salter

The Long Wavelength Array (LWA) will be a new multi-purpose radio telescope operating in the frequency range 10-88 MHz. Scientific programs include pulsars, supernova remnants, general transient searches, radio recombination lines, solar…

天体物理仪器与方法 · 物理学 2012-06-11 G. B. Taylor , The LWA Collaboration

Reaching the thermal noise at low frequencies with the next generation of instruments (e.g. SKA, LOFAR etc.) is going to be a challenge. It requires the development of more advanced techniques of calibration compared to those used from the…

天体物理仪器与方法 · 物理学 2010-08-31 Emanuela Orrú , Huib Intema

We present new Very Large Array (VLA) radio images at 74 and 324 MHz of the SNR W44. The VLA images, obtained with unprecedented angular resolution and sensitivity for such low frequencies have been used in combination with existing 1442…

天体物理学 · 物理学 2009-11-13 G. Castelletti , G. Dubner , C. Brogan , N. E. Kassim

This paper introduces a new program to find high-redshift radio galaxies in the southern hemisphere through ultra-steep spectrum (USS) selection. We define a sample of 234 USS radio sources with spectral indices alpha_408^843 < -1.0 and…

天体物理学 · 物理学 2009-11-13 J. W. Broderick , J. J. Bryant , R. W. Hunstead , E. M. Sadler , T. Murphy

We present a 1.4-GHz catalog of 810 radio sources (560 sources in the complete sample) with 1.8" resolution found within a 17' radius in the SSA13 field (RA=13h12m,DEC=42d38'). The radio image from the VLA has an rms noise level of 4.82…

The Faint Sky Variability Survey is aimed at finding photometric and/or astrometric variable objects in the brightness range between 16<V<24 on timescales between tens of minutes and years with photometric precisions ranging from 3…

天体物理学 · 物理学 2009-11-07 Paul J. Groot , Paul M. Vreeswijk , Mark E. Huber

A host of new low-frequency radio telescopes seek to measure the 21-cm transition of neutral hydrogen from the early universe. These telescopes have the potential to directly probe star and galaxy formation at redshifts $20 \gtrsim z…

We present total flux densities of 1049 radio sources in the frequency range from 151 MHz to 10.6 GHz. These sources belong to the B3-VLA sample, which is complete down to 100 mJy at 408 MHz. The data constitute a homogeneous spectral…

天体物理学 · 物理学 2009-10-31 M. Vigotti , L. Gregorini , U. Klein , K. -H. Mack

Deep radio observations at 1.4GHz for the Extended Chandra Deep Field South were performed in June through September of 2007 and presented in a first data release (Miller et al. 2008). The survey was made using six separate pointings of the…

宇宙学与河外天体物理 · 物理学 2015-06-12 N. A. Miller , M. Bonzini , E. B. Fomalont , K. I. Kellermann , V. Mainieri , P. Padovani , P. Rosati , P. Tozzi , S. Vattakunnel

We present LOFAR High-Band Array (HBA) observations of the Herschel-ATLAS North Galactic Pole survey area. The survey we have carried out, consisting of four pointings covering around 142 square degrees of sky in the frequency range…