The 1.28 GHz MeerKAT DEEP2 Image

Autor: K. M. B. Asad, T. E. Monama, E. F. Bauermeister, Bruce Merry, O. Toruvanda, S. J. Marais, B. M. Lunsky, L. C. Schwardt, H. Bester, H. Kriel, M. Geyer, S. February, B. H. Wallace, M. Serylak, S. N. Twum, N. Kriek, B. Taljaard, M. A. Dikgale-Mahlakoana, W. S. New, K. Madisa, R. M. Adam, Oleg Smirnov, S. Fataar, R. Millenaar, Z. R. Ramudzuli, S. Gounden, I. P. Theron, K. J. Ngoasheng, Z. B. Brits, J. Horrell, G. Stone, D. H. Botha, T. W. Kusel, B. Xaia, M. J. Hlakola, B. S. Frank, S. W. P. Esterhuyse, Jason Manley, James J. Condon, A. Robyntjies, J. A. Malan, Gyula I. G. Józsa, A. A. Patel, R. R. G. Gamatham, Justin L. Jonas, S. C. Gumede, R. Siebrits, A. J. T. Ramaila, M. T. O. Ockards, Nadeem Oozeer, J. P. Burger, A. Loots, M. A. Aldera, L. G. Magnus, R. P. M. Julie, B. L. Fanaroff, G. Fadana, Robert Lehmensiek, A. J. Otto, A. van der Byl, T. Mauch, T. J. van Balla, S. K. Sirothia, L. Sofeya, P. P. A. Kotzé, N. Mnyandu, M. S. de Villiers, T. Cheetham, J. S. Kenyon, R. Renil, J. M. Chalmers, Ian Heywood, A. M. Matthews, L. Richter, F. Kapp, S. Salie, A. R. Isaacson, I. P. T. Moeng, A. Peens-Hough, R. T. Lord, Dirk I. L. de Villiers, W. D. Cotton, V. A. Kasper, J. P. L. Main, Sharmila Goedhart, B. Hugo, L. P. Williams, C. Tasse, L. R. S. Brederode, A. Martens, M. G. Welz, S. J. Buchner, T. D. Abbott, Simon Perkins, M. C. Mphego, C.G. Van der Merwe, V. Van Tonder, C. T. G. Schollar, L. J. du Toit, Fernando Camilo, O. J. Mokone, A. J. Tiplady, T. G. H. Bennett, B. Ngcebetsha
Rok vydání: 2019
Předmět:
DOI: 10.48550/arxiv.1912.06212
Popis: 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 $0.55 \pm 0.01$ $\mu$Jy/beam rms noise. Its J2000 center position $\alpha=04^h 13^m 26.4^s$, $\delta=-80^\circ 00' 00''$ 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 differential source count by combining a power-law count fit to the DEEP2 confusion $P(D)$ distribution from $0.25$ to $10$ $\mu$Jy with counts of individual DEEP2 sources between $10$ $\mu$Jy and $2.5$ mJy. Most sources fainter than $S \sim 100$ $\mu$Jy are distant star-forming galaxies obeying the FIR/radio correlation, and sources stronger than $0.25$ $\mu$Jy account for $\sim93\%$ of the radio background produced by star-forming galaxies. For the first time, the DEEP2 source count has reached the depth needed to reveal the majority of the star formation history of the universe. A pure luminosity evolution of the 1.4 GHz local luminosity function consistent with the Madau & Dickinson (2014) model for the evolution of star-forming galaxies based on UV and infrared data underpredicts our 1.4 GHz source count in the range $-5 \lesssim \log[S(\mathrm{Jy})] \lesssim -4$.
Comment: 20 pages, 18 figures. Accepted for publication in ApJ
Databáze: OpenAIRE
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