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September / October 2011
In this issue
SKA South Africa shines at the SKA Forum 2011
Road to final site decision
MeerKAT passes Preliminary Design Review
More industry contracts for SKA South Africa
PAPER array extended to 64 dishes
Agreements boost SA's bid
Crucial cold receivers installed on KAT-7
Progress with KAT-7 commissioning
On-site UPS for KAT-7
Control and monitoring upgrades for KAT-7
KAT-7 digital back-end acceptance test procedure
Realistic MeerKAT movie
SKA SA bursar wins top UCT research award
SA promotes the African SKA bid abroad
SKA SA presentations in London - Youth Day 2011
Outreach programme wins international award
Mission MeerKAT - the adventure continues

PAPER array extended to 64 dishes



"Scientists who will be using PAPER were very impressed with preliminary images from the instrument, proving that the Karoo region is ideal for this type of research," says William Walbrugh, junior project manager for PAPER based at the MeerKAT office in Cape Town. "We plan to extend PAPER to 128 antennas by 2013."
   
After a very successful deployment, the Precision Array for Probing the Epoch of Reionisation or PAPER experiment is now a proud 64-antenna array. Collaborators from the US (National Radio Astronomy Observatory and Universities of Virginia, Berkeley and Pennsylvania) gathered in the Karoo to accomplish this feat within a mere three week timeframe.

The recent deployment involved the assembly and installation of an additional 26 dipole antennas constructed from parts shipped from the USA. New antenna positions were accurately marked during a previous deployment, with the array being in a minimum redundancy configuration to optimise image quality. Subsequently, hundreds of metres of overground cables were carefully laid to the central computing container in such a way as to avoid cable cross-talk, and simplify the process of array reconfiguration. Furthermore, new analogue receivers were installed and the digital backend was upgraded, featuring a new 64-input ROACH-based correlator.

Concurrent with the deployment, two essential additions were made to the PAPER infrastructure. Grid electrical power, conditioned via a UPS system at the KAT-7 site, has now replaced a diesel generator. Together with this, a fibre optic data cable was installed along a 2 km trench to the nearest KAT-7 infrastructure. This data link will enable remote monitoring and power cycling of the instrument, and also allow distant scientists to download data fragments in order to evaluate the instrument's performance whilst data is recorded to a bulk storage unit within the computing container.


A small part of the 64-antenna PAPER array.


Intern technicians from the Hartebeesthoek Radio Astronomy Observatory helped to install the new PAPER antennas - they are (fltr) Monde Manzini, Raphael van Rensburg and Khulekhani Zulu.