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相关论文: A survey for the missing hydrogen in high redshift…

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With the goal of investigating the nature and the environment of the faint radio sources (at mJy level), here are presented results of X-ray dentifications of Faint Imaging Radio Survey at Twenty centimetres (FIRST) in the 9 square degrees…

宇宙学与河外天体物理 · 物理学 2015-05-13 Khadija EL Bouchefry

The Phoenix Deep Survey is a multi-wavelength survey based on deep 1.4 GHz radio imaging, reaching well into the sub-100 microJy level. One of the aims of this survey is to characterize the sub-mJy radio population, exploring its nature and…

天体物理学 · 物理学 2008-12-18 J. Afonso , A. Georgakakis , C. Almeida , A. M. Hopkins , L. E. Cram , B. Mobasher , M. Sullivan

High-redshift radio galaxies (HzRGs) are among the most massive galaxies in the Universe and sites of extreme active galactic nuclei (AGN) feedback processes, powering energetic radio jets. They are typically embedded in giant Ly$\alpha$…

A 10-arcmin field around the HDF(N) contains 92 radio sources >40 uJy, resolved by MERLIN+VLA at 0".2-2".0 resolution. 55 have Chandra X-ray counterparts including 18 with a hard X-ray photon index and high luminosity characteristic of a…

Identifying the optical/near-infrared (NIR) counterparts to the distant submillimeter (submm) source population has proved difficult due to poor submm spatial resolution. However, the proportionality of both centimeter and submm data to the…

天体物理学 · 物理学 2007-05-23 A. J. Barger , L. L. Cowie , E. A. Richards

We present the results of a survey for intervening HI 21-cm absorbers at intermediate and low redshift (0<z<1.2). For our total sample of 24 systems, we obtained high quality data for 17 systems, the other seven being severely affected by…

星系天体物理 · 物理学 2015-09-09 M. A. Zwaan , J. Liske , C. Péroux , M. T. Murphy , N. Bouché , S. J. Curran , A. D. Biggs

The star-forming reservoir in the distant Universe can be detected through HI 21-cm absorption arising from either cool gas associated with a radio source or from within a galaxy intervening the sight-line to the continuum source. In order…

星系天体物理 · 物理学 2016-08-23 S. J. Curran , S. W. Duchesne , A. Divoli , J. R. Allison

H II regions are the signposts of massive ($M\geq\,8\,M_\odot$) star-forming sites in our Galaxy. It has been observed that the ionizing photon rate inferred from the radio continuum emission of H II regions is significantly lower ($\sim$…

We present the results of a search for associated 21 cm HI absorption at redshift 0.42 < z < 1.00 in radio-loud galaxies from three Galaxy And Mass Assembly (GAMA) survey fields. These observations were carried out as part of a pilot survey…

We present a preliminary survey of 58 radio sources within the isoplanatic patches (r < 25") of bright (11<R<12) stars suitable for use as natural guide stars with high-order adaptive optics (AO). An optical and near-infrared imaging survey…

宇宙学与河外天体物理 · 物理学 2014-11-20 B. Stalder , K. C. Chambers , William D. Vacca

We present results from two surveys for radio-loud quasars. These are (1) a northern survey reaching S(5GHz)=0.2Jy and (2) the Parkes QSO survey reaching S(2.7GHz)=0.25Jy, which together cover most of the sky. Both surveys use digitised…

天体物理学 · 物理学 2007-05-23 I. M. Hook , P. A. Shaver , R. G. McMahon

High-redshift radio-loud quasars are used to, among other things, test the predictions of cosmological models, set constraints on black hole growth in the early universe and understand galaxy evolution. Prior to this paper, 20 extragalactic…

We have used the Submillimeter Array to image a flux limited sample of seven submillimeter galaxies, selected by the AzTEC camera on the JCMT at 1.1 mm, in the COSMOS field at 890um with 2" resolution. All of the sources - two radio-bright…

We present a statistical study of the environments of 63 high-redshift radio galaxies (HzRGs) between redshifts 1<z<5.2, using the 24um, waveband of the MIPS instrument aboard the Spitzer Space Telescope. Using a counts-in-cell analysis, a…

宇宙学与河外天体物理 · 物理学 2015-06-04 Jack H. Mayo , Joel Vernet , Carlos De Breuck , Audrey Galametz , Nick Seymour , Daniel Stern

We have obtained high dynamic range, good natural seeing i' images of BL Lacertae objects (BL Lacs) to search for the AGN host and thus constrain the source redshift. These objects are drawn from a sample of bright flat-spectrum radio…

宇宙学与河外天体物理 · 物理学 2015-05-18 Aaron M. Meisner , Roger W. Romani

Ultra-deep radio surveys are an invaluable probe of dust-obscured star formation, but require a clear understanding of the relative contribution from radio AGN to be used to their fullest potential. We study the composition of the $\mu$Jy…

The Australia Telescope Compact Array (ATCA) has been used to survey at 1.4GHz, a small region (< 3 sq deg) overlapping with the 2dF Galaxy Redshift Survey (Colless et al. 2001, MNRAS, 328, 1039). We surveyed with a varying radio…

天体物理学 · 物理学 2009-11-10 B. H. P. Chan , L. E. Cram , E. M. Sadler , N. E. B. Killeen , C. A. Jackson , B. Mobasher , R. D. Ekers

We explore the radio properties of powerful (rest-frame luminosity $\gtrsim10^{28}$ W Hz$^{-1}$ at 500 MHz) high-redshift (z > 3.5) quasars. The aim of this study is to gain a better understanding of radio-loud sources at the epoch when…

星系天体物理 · 物理学 2024-07-02 Alessandro Capetti , Barbara Balmaverde

We present submillimetre (SCUBA) photometry of a sample of eight high-redshift (2.5 < z < 3.5) radio quasars from two redshift surveys: the TEXOX-1000, or TOOT, survey; and the 7C Redshift Survey (7CRS). Unlike the powerful high-redshift…

Surveys to find high-redshift radio galaxies deliberately exclude optically-bright objects, which may be distant radio-loud quasars. In order to properly determine the space density of supermassive black holes, the fraction of such objects…

天体物理学 · 物理学 2009-11-07 Chris Simpson