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TOPIC: Karoo Array Telescope


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MeerKAT
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SKA precursor telescope MeerKAT releases new 1.5 images using its current 32 antennas

The South African SKA precursor telescope MeerKAT has just released its recent AR1.5 results, images achieved by using various configurations of the 32 antennas currently operational in the Karoo.
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Karoo Array Telescope
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Title: KAT-7 Science Verification: Using HI Observations of NGC 3109 to Understand its Kinematics and Mass Distribution
Authors: C. Carignan (1), B. S. Frank (1), K. M. Hess (1), D. M. Lucero (1), T. H. Randriamampandry (1), S. Goedhart (2), S. S. Passmoor ((1) Department of Astronomy, University of Cape Town, (2) SKA South Africa)

HI observations of the Magellanic-type spiral NGC 3109, obtained with the seven dish Karoo Array Telescope (KAT-7), are used to analyse its mass distribution. Our results are compared to what is obtained using VLA data. KAT-7 is the precursor of the SKA pathfinder MeerKAT, which is under construction. The short baselines and low system temperature of the telescope make it sensitive to large scale low surface brightness emission. The new observations with KAT-7 allow the measurement of the rotation curve of NGC 3109 out to 32', doubling the angular extent of existing measurements. A total HI mass of 4.6 x 10^8 solar masses is derived, 40% more than what was detected by the VLA observations.
The observationally motivated pseudo-isothermal dark matter (DM) halo model can reproduce very well the observed rotation curve but the cosmologically motivated NFW DM model gives a much poorer fit to the data. While having a more accurate gas distribution has reduced the discrepancy between the observed RC and the MOdified Newtonian Dynamics (MOND) models, this is done at the expense of having to use unrealistic mass-to-light ratios for the stellar disk and/or very large values for the MOND universal constant a0. Different distances or HI contents cannot reconcile MOND with the observed kinematics, in view of the small errors on those two quantities. As for many slowly rotating gas-rich galaxies studied recently, the present result for NGC 3109 continues to pose a serious challenge to the MOND theory.

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MeerKAT telescope arra
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General Dynamics to deliver 64 radio antennas specially designed for MeerKAT telescope array in Northern Cape province of South Africa

General Dynamics SATCOM Technologies is partnering with Stratosat Datacom (Pty) Ltd. to supply 64 radio-telescope antennas, ancillary electronic components and support for South Africa's MeerKAT radio telescope program.
The Stratosat/General Dynamics SATCOM consortium will perform a minimum of 75 percent of the work on the 632 million rand ($75 million) contract in South Africa to maximize the skill development and involvement of its local industry, including the qualification testing, tooling design and virtually all of the manufacturing.

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Posts: 129963
Date:
MeerKAT
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Tenders are hereby invited for the procurement of vehicles for the operation at the Karoo site.
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Posts: 129963
Date:
Karoo Array Telescope
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International panel thumbs-up for SA radio telescope

Engineering News reports that the MeerKAT radio telescope, a precursor to the Square Kilometre Array (SKA), had a successful first test, with an international panel of experts declaring that the MeerKAT has passed its preliminary design review (PDR) with distinction.
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Title: Looking At the Distant Universe with the MeerKAT Array (LADUMA)
Authors: B.W. Holwerda (ESA-ESTEC), S.--L. Blyth (ACGC, University of Cape Town), A. J. Baker (Rutgers University), the LADUMA team

The MeerKAT (64 x 13.5m dish radio interferometer) is South Africa's precursor instrument for the Square Kilometre Array (SKA), exploring dish design, instrumentation, and the characteristics of a Karoo desert site and is projected to be on sky in 2016. One of two top-priority, Key Projects is a single deep field, integrating for 5000 hours total with the aim to detect neutral atomic hydrogen through its 21 cm line emission out to redshift unity and beyond.
This first truly deep HI survey will help constrain fueling models for galaxy assembly and evolution. It will measure the evolution of the cosmic neutral gas density and its distribution over galaxies over cosmic time, explore evolution of the gas in galaxies, measure the Tully-Fisher relation, measure OH maser counts, and address many more topics.
Here we present the observing strategy and envisaged science case for this unique deep field, which encompasses the Chandra Deep Field-South (and the footprints of GOODS, GEMS and several other surveys) to produce a singular legacy multi-wavelength data-set.

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Posts: 129963
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MESMER
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Title: MESMER: MeerKAT Search for Molecules in the Epoch of Reionisation
Authors: I. Heywood, R. P. Armstrong, R. Booth, A. J. Bunker, R. P. Deane, M. J. Jarvis, J. L. Jonas, M. E. Jones, H-R. Kloeckner, J-P. Kneib, K. K. Knudsen, F. Levrier, D. Obreschkow, D. Rigopoulou, J. Dunlop, M. G. Santos, E. R. Stanway, C. Willott

Observations of molecular gas at all redshifts are critical for measuring the cosmic evolution in molecular gas density and understanding the star-formation history of the Universe. The 12CO molecule (J=1-0 transition = 115.27 GHz) is the best proxy for extragalactic H2, which is the gas reservoir from which star formation occurs, and has been detected out to z~6. Typically, redshifted high-J lines are observed at mm-wavelengths, the most commonly targeted systems exhibiting high SFRs (e.g. submm galaxies), and far-IR-bright QSOs. While the most luminous objects are the most readily observed, detections of more typical galaxies with modest SFRs are essential for completing the picture. ALMA will be revolutionary in terms of increasing the detection rate and pushing the sensitivity limit down to include such galaxies, however the limited FoV when observing at such high frequencies makes it difficult to use ALMA for studies of the large-scale structure traced out by molecular gas in galaxies. This article introduces a strategy for a systematic search for molecular gas during the EoR (z~7 and above), capitalizing on the fact that the J=1-0 transition of 12CO enters the upper bands of cm-wave instruments at high-z. The FoV advantage gained by observing at such frequencies, coupled with modern broadband correlators allows significant cosmological volumes to be probed on reasonable timescales. In this article we present an overview of our future observing programme which has been awarded 6,500 hours as one of the Large Survey Projects for MeerKAT, the forthcoming South African SKA pathfinder instrument. Its large FoV and correlator bandwidth, and high-sensitivity provide unprecedented survey speed for such work. An existing astrophysical simulation is coupled with instrumental considerations to demonstrate the feasibility of such observations and predict detection rates.

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MeerKAT construction delayed

Construction of the MeerKAT telescope is being extended to allow SA time to perfect the telescope technology in a bid to beat Australia in a competition to host the Square Kilometre Array (SKA).
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Posts: 129963
Date:
MeerKAT radio telescope
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South Africa's MeerKAT radio telescope team said the telescope had elicited interest and demand for usage allocations from all over the globe.
This is despite the stelescope, which is part of a proposed Square Kilometre Array (SKA), being almost five years away from being fully operational.
The MeerKAT is set to be built near Carnavon in the Northen Cape province. It will consist of 64 dishes measuring around 13.5m each in diameter. Already seven dishes have been installed.

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Posts: 129963
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RE: Karoo Array Telescope
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This year, 2010, is going to be a key year in the history of science, engineering and technology in South Africa as the country's globally significant radio astronomy programme reaches key milestones.
South Africa has created a Radio Astronomy Reserve in the Karoo, around and west of the small town of Carnarvon in the Northern Cape province, and is currently developing the MeerKAT radio telescope array which, when it starts operation in 2013, will be one of the biggest and most important such instruments in the world.

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