I. Heywood, I. Rammala, F. Camilo, W. D. Cotton, F. Yusef-Zadeh, T. D. Abbott, R. M. Adam, G. Adams, M. A. Aldera, K. M. B. Asad, E. F. Bauermeister, T. G. H. B… 展开作者
I. Heywood, I. Rammala, F. Camilo, W. D. Cotton, F. Yusef-Zadeh, T. D. Abbott, R. M. Adam, G. Adams, M. A. Aldera, K. M. B. Asad, E. F. Bauermeister, T. G. H. Bennett, H. L. Bester, W. A. Bode, D. H. Botha, A. G. Botha, L. R. S. Brederode, S. Buchner, J. P. Burger, T. Cheetham, D. I. L. de Villiers, M. A. Dikgale-Mahlakoana, L. J. du Toit, S. W. P. Esterhuyse, B. L. Fanaroff, S. February, D. J. Fourie, B. S. Frank, R. R. G. Gamatham, M. Geyer, S. Goedhart, M. Gouws, S. C. Gumede, M. J. Hlakola, A. Hokwana, S. W. Hoosen, J. M. G. Horrell, B. Hugo, A. I. Isaacson, G. I. G. Józsa, J. L. Jonas, A. F. Joubert, R. P. M. Julie, F. B. Kapp, J. S. Kenyon, P. P. A. Kotzé, N. Kriek, H. Kriel, V. K. Krishnan, R. Lehmensiek, D. Liebenberg, R. T. Lord, B. M. Lunsky, K. Madisa, L. G. Magnus, O. Mahgoub, A. Makhaba, S. Makhathini, J. A. Malan, J. R. Manley, S. J. Marais, A. Martens, T. Mauch, B. C. Merry, R. P. Millenaar, N. Mnyandu, O. J. Mokone, T. E. Monama, M. C. Mphego, W. S. New, B. Ngcebetsha, K. J. Ngoasheng, M. T. Ockards, N. Oozeer, A. J. Otto, S. S. Passmoor, A. A. Patel, A. Peens-Hough, S. J. Perkins, A. J. T. Ramaila, N. M. R. Ramanujam, Z. R. Ramudzuli, S. M. Ratcliffe, A. Robyntjies, S. Salie, N. Sambu, C. T. G. Schollar, L. C. Schwardt, R. L. Schwartz, M. Serylak, R. Siebrits, S. K. Sirothia, M. Slabber, O. M. Smirnov, L. Sofeya, B. Taljaard, C. Tasse, A. J. Tiplady, O. Toruvanda, S. N. Twum, T. J. van Balla, A. van der Byl, C. van der Merwe, V. Van Tonder, R. Van Wyk, A. J. Venter, M. Venter, B. H. Wallace, M. G. Welz, L. P. Williams, B. Xaia
备注：
29 pages, 15 figures, 3 tables, accepted for publication in the The Astrophysical Journal. Replacement arXiv version with higher quality figures
The inner $\sim$200 pc region of the Galaxy contains a 4 million M$_{\odot}$ supermassive black hole (SMBH), significant quantities of molecular gas, and star formation and cosmic ray energy densities that are roughly two orders of magnitude higher than the corresponding levels in the Galactic disk. At a distance of only 8.2 kpc, the region presents astronomers with a unique opportunity to study a diverse range of energetic astrophysical phenomena, from stellar objects in extreme environments, to the SMBH and star-formation driven feedback processes that are known to influence the evolution of galaxies as a whole. We present a new survey of the Galactic center conducted with the South African MeerKAT radio telescope. Radio imaging offers a view that is unaffected by the large quantities of dust that obscure the region at other wavelengths, and a scene of striking complexity is revealed. We produce total intensity and spectral index mosaics of the region from 20 pointings (144 hours on-target in total), covering 6.5 square degrees with an angular resolution of 4$"$,at a central frequency of 1.28 GHz. Many new features are revealed for the first time due to a combination of MeerKAT's high sensitivity, exceptional $u,v$-plane coverage, and geographical vantage point. We highlight some initial survey results, including new supernova remnant candidates, many new non-thermal filament complexes, and enhanced views of the Radio Arc Bubble, Sgr A and Sgr B regions. This project is a SARAO public legacy survey, and the image products are made available with this article.
The IRAS Revised Bright Galaxy Sample (RBGS) comprises galaxies and unresolved mergers stronger than $S = 5.24$ Jy at $λ= 60~μ\mathrm{m}$ with galactic latitudes $\vert b \vert > 5^\circ$. Nearly all are dusty star-forming galaxies whose radio continuum and far-infrared luminosities are proportional to their current rates of star formation. We used the MeerKAT array of 64 dishes to make $5 \times 3$ min snapshot observations at $ν= 1.28$ GHz covering all 298 southern (J2000 $δ< 0^\circ$) RBGS sources identified with external galaxies. The resulting images have $θ\approx 7.5$ arcsec FHWM resolu…
The MeerKAT 1.3 GHz Survey of the Large Magellanic Cloud
National Radio Astronomy Observatory（国家无线电天文台）；South African Radio Astronomy Observatory（南非无线电天文台）；Western Sydney University（西悉尼大学）；Faculty of Engineering, Gifu University（岐阜大学工程学院）；Centre for Radio Astronomy Techniques and Technologies (RATT), Department of Physics and Electronics, Rhodes University（罗德斯大学物理与电子学院射电天文技术与方法中心）；Institute for Radio Astronomy, National Institute of Astrophysics (INAF IRA)（意大利国家天体物理研究所射电天文研究所）；Lennard-Jones Laboratories, Keele University（基尔大学伦纳德-琼斯实验室）
The MeerKAT 1.3 GHz survey of the Large Magellanic Cloud: Point Source Catalogue
Western Sydney University（西悉尼大学）；National Radio Astronomy Observatory（美国国家射电天文台）；South African Radio Astronomy Observatory (SARAO)（南非射电天文台）；Keele University（基尔大学）
This paper is part of a series discussing the results obtained in the framework of a wide international collaboration - the Lockman Hole Project - aimed at improving the extensive multiband coverage available in the Lockman Hole region, through novel deep, wide-area, multifrequency (60, 150, 350 MHz, and 1.4 GHz) radio surveys. This multifrequency, multi-band information will be exploited to get a comprehensive view of star formation and active galactic nucleus activities in the high-redshift Universe from a radio perspective. In this paper, we present novel 1.4 GHz mosaic observations obtaine…
We present a preparatory spectroscopic survey to identify radio-bright, high-redshift quasars for the MeerKAT Absorption Line Survey (MALS). The candidates have been selected on the basis of a single flux density limit at 1.4 GHz (>200 mJy) together with mid-infrared color criteria from the Wide-field Infrared Survey Explorer (WISE). Through spectroscopic observations using the Nordic Optical Telescope, we identify 72 quasars out of 99 candidates targeted. We measure the spectroscopic redshifts based on characteristic, broad emission lines present in the spectra. Of these 72 quasars, 64 and 48…
We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one $\approx 68'$ FWHM primary beam area with $7.6''$ FWHM resolution and $0.55 \pm 0.01$ $μ$Jy/beam rms noise. Its J2000 center position $α=04^h 13^m 26.4^s$, $δ=-80^\circ 00' 00''$ was selected to minimize artifacts caused by bright sources. We introduce the new 64-element MeerKAT array and describe commissioning observations to measure the primary beam attenuation pattern, estimate telescope pointing errors, and pinpoint $(u,v)$ coordinate errors caused by offsets in frequency or time. We constructed a 1.4 GHz differenti…
We present new observations of Fornax A taken at 1 GHz with the MeerKAT telescope and at 6 GHz with the Sardinia Radio Telescope (SRT). The sensitive (noise ~16 micro-Jy beam$^{-1}$), high resolution ( < 10'') MeerKAT images show that the lobes of Fornax A have a double-shell morphology, where dense filaments are embedded in a diffuse and extended cocoon. We study the spectral properties of these components by combining the MeerKAT and SRT observations with archival data between 84 MHz and 217 GHz. For the first time, we show that multiple episodes of nuclear activity must have formed the exte…
In this paper we present results from a radio-optical study of the galaxy populations of the galaxy clusters Abell 1300 and MACS J1931.8$-$2634, a merger and a relaxed system respectively both located at $z \sim 0.3$, aimed at finding evidence of merger-induced radio emission. Radio observations are taken at 1.28 GHz with the MeerKAT interferometer during its early-stage commissioning phase, and combined with archive optical data. We generated catalogues containing 107 and 162 radio sources in the A$~$1300 and MACS J1931.8--2634 cluster fields respectively, above a 0.2 mJy threshold and within…
The MeerKAT Massive Distant Clusters Survey: a search for diffuse radio emission in 30 massive SZ-selected clusters at $z > 1$
University of the Witwatersrand（威特沃特斯兰德大学）；University of KwaZulu-Natal（夸祖鲁-纳塔尔大学）；Rhodes University（罗德斯大学）；South African Radio Astronomy Observatory（南非射电天文观测台）
Variability of Sagittarius A* at 3 GHz on minute-scale with MeerKAT
Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）；Argelander Institute for Astronomy, University of Bonn（波恩大学阿尔冈德天体物理研究所）；Deutsches Zentrum für Astrophysik（德国天体物理中心）；Thüringer Landessternwarte（图林根州立天文台）；Instituto de Astrofísica de Andalucía-CSIC（安达卢西亚天体物理研究所（CSIC））；Center for Astrophysics | Harvard & Smithsonian（哈佛史密森尼天体物理中心）；South African Radio Astronomy Observatory（南非射电天文观测站）
MOSS III: MeerKATs view on the galaxy populations in two massive galaxy clusters
Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL)（洛桑联邦理工学院物理研究所）；Astronomical Observatory Institute, Faculty of Physics, Adam Mickiewicz University（亚当·密茨凯维奇大学物理学院天文台研究所）；National Radio Astronomy Observatory (NRAO)（美国国家射电天文台）；Tartu Observatory, University of Tartu（塔尔图大学塔尔图天文台）；National Centre for Radio Astrophysics, Tata Institute of Fundamental Research（塔塔基础研究院国家射电天体物理学中心）
Recent MeerKAT radio continuum observations of the Galactic center at 20 cm show a large population of nonthermal radio filaments (NRFs) in the inner few hundred pc of the Galaxy. We have selected a sample of 57 radios ources, mainly compact objects, in the MeerKAT mosaic image that appear to be associated with NRFs. The selected sources are about 4 times the number of radio point sources associated with filaments than would be expected by random chance. Furthermore, an apparent correlation between bright IR stars and NRFs is inferred from their similar latitude distributions, suggesting that …
We present the discovery of a single radio relic located at the edge of the galaxy cluster A2384, using the MeerKAT radio telescope. A2384 is a nearby ($z$ = 0.092), low mass, complex bimodal, merging galaxy cluster that displays a dense X-ray filament ($\sim$ 700 kpc in length) between A2384(N) (Northern cluster) and A2384(S) (Southern cluster). The origin of the radio relic is puzzling. By using the MeerKAT observation of A2384, we estimate that the physical size of the radio relic is 824 $\times$ 264 kpc$^{2}$ and that it is a steep spectrum source. The radio power of the relic is $P_{1.4\m…
The Bullet cluster (1E 0657-55.8) is a massive merging system at redshift $z$=0.296, known to host a powerful radio halo and a relic. Here we present high fidelity MeerKAT L-band (0.9-1.7 GHz) observations of the Bullet cluster, in which we trace a larger extent of both the radio halo and relic in comparison to previous studies. The size of the recovered radio halo is 1.6 Mpc $\times$ 1.3 Mpc and the largest linear size of the relic is ~988 kpc. We detect a new decrement feature on the southern outskirts of the halo emission, where a region appears to have a lower surface brightness in compari…
Ram pressure stripping is a crucial evolutionary driver for cluster galaxies. It is thought to be able to accelerate the evolution of their star formation, trigger the activity of their central active galactic nucleus (AGN) and the interplay between the galactic and environmental gas, and eventually dissipate their gas reservoir. We explored the outcomes of ram pressure stripping by studying the non-thermal radio emission of the jellyfish galaxy JW100 in the cluster Abell 2626 ($z=0.055$) by combining LOFAR, MeerKAT, and VLA observations from 0.144 to 5.5 GHz. We studied the integrated spectra…
X-ray counterparts to stellar MeerKAT Galactic-plane compact radio sources
University of Cape Town（开普敦大学）；South African Astronomical Observatory（南非天文台）；Radboud University（拉德堡德大学）；University of the Free State（自由州大学）；Hamburger Sternwarte, University of Hamburg（汉堡天文台，汉堡大学）；Leibniz-Institut für Astrophysik Potsdam (AIP)（波茨坦天体物理研究所（AIP））；Max-Planck-Institut für extraterrestrische Physik（马克斯·普朗克地外物理研究所）；Institut für Astronomie Astrophysik, Eberhard Karls Universität Tübingen（蒂宾根大学天文学与天体物理研究所）
MIGHTEE is a galaxy evolution survey using simultaneous radio continuum, spectro-polarimetry, and spectral line observations from the South African MeerKAT telescope. When complete, the survey will image $\sim$20 deg$^{2}$ over the COSMOS, E-CDFS, ELAIS-S1, and XMM-LSS extragalactic deep fields with a central frequency of 1284 MHz. These were selected based on the extensive multiwavelength datasets from numerous existing and forthcoming observational campaigns. Here we describe and validate the data processing strategy for the total intensity continuum aspect of MIGHTEE, using a single deep po…
An HI+radio continuum study of local cluster galaxies: Intercepting the early stages of environmental processing with MeerKAT
INAF - Osservatorio Astronomico di Padova（意大利国家天体物理研究所帕多瓦天文台）；Astronomical Institute of the Czech Academy of Sciences（捷克科学院天文研究所）；INAF - Osservatorio Astronomico di Cagliari（意大利国家天体物理研究所卡利亚里天文台）；University of Bologna（博洛尼亚大学）；INAF - Istituto di Radioastronomia（意大利国家天体物理研究所射电天文研究所）；ESO（欧洲南方天文台）；Leibniz Institute for Astrophysics Potsdam (AIP)（波茨坦市莱布尼兹天体物理研究所）；Centre for Radio Astronomy Techniques and Technologies (RATT), Department of Physics and Electronics, Rhodes University（罗德斯大学物理与电子学院射电天文技术与方法中心）；Institute for Fundamental Physics of the Universe（宇宙基础物理研究所）；SISSA - International School for Advanced Studies（国际高等研究院）；INAF - Osservatorio Astronomico di Trieste（意大利国家天体物理研究所的里雅斯特天文台）
Intensity mapping (IM) with neutral hydrogen is a promising avenue to probe the large scale structure of the Universe. In this paper, we demonstrate that using the 64-dish MeerKAT radio telescope as a connected interferometer, it is possible to make a statistical detection of HI in the post-reionization Universe. With the MIGHTEE (MeerKAT International GHz Tiered Extragalactic Exploration) survey project observing in the L-band ($856 < ν< 1712$ MHz, $z < 0.66$), we can achieve the required sensitivity to measure the HI IM power spectrum on quasi-linear scales, which will provide an important c…
We present deep 1.4 GHz source counts from $\sim$5 deg$^2$ of the continuum Early Science data release of the MeerKAT International Gigahertz Tiered Extragalactic Exploration (MIGHTEE) survey down to $S_{1.4\textrm{GHz}}\sim$15 $μ$Jy. Using observations over two extragalactic fields (COSMOS and XMM-LSS), we provide a comprehensive investigation into correcting the incompleteness of the raw source counts within the survey to understand the true underlying source count population. We use a variety of simulations that account for: errors in source detection and characterisation, clustering, and v…
