Square Kilometre Array Australia

NewsletterNewsletter 16, December 2007

This is one of a series of Newsletters to keep interested parties informed about the progress of activities in Australasia related to the SKA radio telescope project. Previous newsletters are available from www.ska.gov.au

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PULSE@Parkes Project Trialled with High School Students (or Australian High School Students Use the Parkes Radio Telescope Remotely)On December 4, 2007 a group of Year 10 and 11 students from Kingswood High School in western Sydney became the first Australian students to observe pulsars via remote control of the iconic Parkes radio telescope. This was the first test of an exciting new educational project, PULSE@Parkes, under development by the CSIRO Australia Telescope National Facility (ATNF).

PULsar Student Exploration online at Parkes involves high school students controlling the Parkes telescope remotely from CSIRO ATNF Headquarters at Marsfield to observe a number of pulsars, analyse their data and discuss their findings with other schools and professional astronomers. Some of the pulsars in the project list are also being observed for the Parkes Pulsar Timing Array project or for GLAST (Gamma Ray Large Area Space Telescope) support

ATNF Summer Student, Matthew Carr (standing), watching the excited Kingswood High students remotely operating the Parkes Radio Telescope.

observations, so the data the students gather feeds in to these important programs as well.

The second school trial, with Muswellbrook High School, takes place in February 2008 after which the project material

ContentsPULSE@Parkes Project 1

ASKAP’s Parkes Phased Array Feed Test-bed 2

Science with ASKAP 2

The Transient Radio Sky – an ASKAP Key Science Driver 3

ASKAP Related Electronics Project Wins EDN Innovation Award 3

Raman Research Institute, India, Joins Murchison Wide-field Array Consortium 4

ALMA Project provides “Lessons Learned” to ASKAP 5

New Operations Model for CSIRO ATNF 5

Murchison Radio-astronomy Observatory’s Proposed Accommodation Upgrade 6

Radio Astronomy Appointments at Curtin University of Technology 6

Australian SKA Planning Office (ASPO) Hands “Baton” to ASCC 7

News from the Australian SKA Coordination Committee – Australia to Host the Second International SKA Forum 7

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will be freely available online. Whilst the number of schools that can directly observe will be limited by time constraints on the telescope, the data and educational materials can be accessed by anyone.

PULSE@Parkes is the first stage in a long-term scheme to develop authentic science projects and educational material in radio astronomy for students. As new telescopes such as the Australian SKA Pathfinder (ASKAP) become operational, schools will have access to data from them integrated into an appropriate educational form. ATNF Education Officer, Robert Hollow, is the education leader for the project and pulsar astronomer, Dr George Hobbs is the science leader.

Robert Hollow, CSIRO ATNF Outreach Officer

ASKAP’s Parkes Phased Array Feed Test-bedDuring December 2007 and January 2008 ASKAP will be commissioning a single, 12-m diameter antenna built by Patriot Antenna Systems at Parkes Observatory. This antenna will provide a dedicated platform for field tests of the Phased Array Feeds (PAFs). The Parkes RFI (Radio Frequency Interference) environment is significantly better than at CSIRO ATNF headquarters in Marsfield. Furthermore the 64-m Parkes telescope provides a platform for deeper, more sensitive testing of the PAF in tandem with the new 12-m antenna.

Although the functional specification and design of this particular 12-m antenna differs from that for the actual ASKAP antennas, it will provide a single dedicated system to test successive generations of PAFs in readiness for ASKAP itself. In particular the antenna will be equipped with a feed rotator at the prime focus to allow the PAF to maintain a constant parallactic angle during observations. This ‘de-rotation’ of the sky means that the data stream from the PAF will be significantly easier to process in the imaging software.

Site preparations, including foundations and services for the Parkes 12-m antenna, have been completed by CSIRO ATNF Parkes staff in consultation with Patriot. The new antenna will be located approximately 400 m E of the 64 m Parkes ‘dish’, parallel to the EW interferometer track, on a level area of land previously leased for farming.

The antenna reflector comprises ‘stretch-formed’ solid panels, and is very similar to the Patriot antenna built for NASA-JPL. The pedestal will house an ASKAP-style beamformer, and one of the challenges for ASKAP is to determine a ventilation system for the pedestal due to its high heat output (estimated to be about 5 kW). We have installed an underground fan-duct system to provide naturally-cooled forced air to the pedestal. Over the first half of 2008 we will assess the efficiency of this system and determine if it will be suitable in Western Australia.

The Parkes 12-m test-bed will be controlled from a newly-refurbished RFI-shielded room in the Parkes “Woolshed”.

Foreground: Foundation pad & bolt ring ready for the 12-m antenna to be constructed at Parkes. Background: the Parkes 64-m dish and a decommissioned 60 ft antenna, which is about to be relocated to the eastern end of the track. Photo Credit: Barry Turner.

The 12-m antenna is currently being shipped to Australia, and some integration work is being done by United Rail at Taree, under subcontract to Patriot.

Dr Carole Jackson, Business Development Manager, ASKAP Antennas Project Manager

Science with ASKAPA paper outlining the ambitious science program for the Australian SKA Pathfinder has been accepted for publication in PASA (Publications of the Astronomical Society of Australia).

The three main goals of ASKAP are to:

carry out world-class, ground-breaking observations directly relevant to the SKA Key Science Projects;

demonstrate and prototype technologies for the mid-frequency SKA, including field-of-view enhancement by focal-plane phased-arrays on new-technology 12 m class parabolic reflectors;

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establish a site for radio astronomy in Western Australia where observations can be carried out free from the harmful effects of radio interference.

As well as detailing ASKAP’s system parameters and capabilities, the paper examines the key science drivers for ASKAP, namely understanding the evolution, formation and population of galaxies including our own, understanding the magnetic universe, revealing the transient radio sky and searching for gravitational waves.

The paper can be found on the pre-print server at http://xxx.lanl.gov/abs/0711.2103 or http://www.atnf.csiro.au/projects/ska/newdocs/askap_pasa07.pdf

In the next few newsletters particular science driver highlights of ASKAP will be described. The first of these is below.

The Transient Radio Sky – an ASKAP Key Science DriverWith its very high sensitivity, high resolution and ability to cover the entire sky in a single day’s observing, ASKAP will be eminently suitable as an instrument to observe transient radio events. One of the advantages of an all-sky survey is that it is tailor-made for detecting the unknown, and the most interesting transient sources detected with ASKAP will undoubtedly be objects about which we are currently ignorant.

Gamma Ray Bursts (GRBs) are a transient phenomenon which, in the gamma-ray waveband, are almost certainly relativistically beamed in a narrow cone aligned with the direction of propagation. This implies that we detect only some small fraction of the total population. However it may be possible to detect “orphan GRBs” – without the initial gamma-ray trigger – by looking for variable radio sources, since the associated radio emission appears to be isotropic and is detectable for several weeks. Several hundred radio afterglows of GRBs should be present in the sky at any one time above a level of 1 mJy (a milli-Jansky is a unit of flux density equivalent to 10229 Watts per square metre per Hertz). ASKAP will be able to survey the sky to this level every day, providing a definitive test of the existence or otherwise of these radio afterglows.

Monitoring the variable flux of a whole range of AGN (Active Galactic Nuclei, another name for some quasars) will also be possible with ASKAP thanks to its sensitivity and wide field-of-view. There are an estimated 17 objects per square degree of sky with a flux density above 10 mJy, thus ASKAP would usefully survey about 350,000 AGN each day. A subset of these AGN will show variability on timescales of less than a day, and ASKAP could measure this intra-day variability in hundreds of thousands of objects, enabling astronomers to

probe the physics that causes the bright emission from such sources in the first place, as well as probe its propagation through our own Galaxy.

Extreme Scattering Events (ESEs) are another type of transient event, a phenomenon for which there is no completely satisfactory physical model, but is likely tied to propagation through small, dense, ionized regions in the Interstellar Medium very near the Solar System. The all-sky monitoring that will be possible with ASKAP will provide crucial new data to help address this problem.

Investigating the origin of ultra-high-energy cosmic rays is another area of research planned for inclusion in ASKAP’s mapping of the transient radio sky. A key to untangling the origin of such cosmic rays is direct detection of ultra-high-energy neutrinos. One promising method of achieving this involves the ability to detect broadband pulses of sub-nanosecond duration, and ASKAP will serve as a first test-bed of nanosecond pulse technology achievable with the SKA.

ASKAP Related Electronics Project Wins EDN Innovation AwardElectronics engineers and researchers from La Trobe University’s Centre for Technology Infusion (CTI), Peregrine Semiconductor Australia (PSA) and the CSIRO’s Australia Telescope National Facility (ATNF) – have won an international design award for a prototype LNA based on Peregrine’s Silicon-on-Sapphire process technology.

The collaboration has won the 2007 EDN Innovation Award for best Application of Analogue Design by international electronics publisher Electronics Design, Strategy, News (EDN) magazine for a Low Noise Amplifier (LNA). Fresh out of design and manufacturing, and now undergoing rigorous performance testing at CSIRO, the LNA has been designed to meet the extremely challenging requirements necessary for radio astronomy receivers.

Radio astronomy demands exquisitely sensitive receiver systems to detect the faint signals of distant astronomical objects. This sensitivity is achieved by building low-noise (characterised as “low-system temperature”) receiver systems. Over many years CSIRO ATNF has made a significant investment in developing broadband receivers for astronomy instrumentation, using state-of-the art substrates, semi-conductors and processes for the receiver components, although on a relatively limited scale.

ASKAP demands many more receiver systems than anything ATNF, or any other radio astronomy application, has ever needed. Each of ASKAP’s 45 phased array feeds will comprise about 200 individual receivers. Each of these 9000 receivers requires a low-noise amplifier to boost the raw detected signal.

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The SKA will be 100 times larger than ASKAP – so the numbers of receiver systems required for it are truly astronomical!

The consortium was particularly keen to try out Peregrine’s “UltraCMOS” patented Silicon-on-Sapphire (SOS) 0.25 micron process, given that SOS promises superior performance to CMOS, having a particularly low-loss substrate, with high Q (low loss) passive components and the potential to maintain these characteristics over the very broad frequency bands required for radio astronomy, a feature very pertinent to the SKA. In electronic engineering terms, according to Professor Jack Singh, Director of La Trobe University’s CTI, the challenge to design the amplifier was formidable.

“The big challenge – and the innovative design in this – was to overcome the inherent noise in an integrated circuit, and to produce an amplifier with the lowest noise possible, with broad frequency band and high gain,” Professor Singh said. “To overcome the inherent noise in an integrated circuit, the La Trobe University team used with great ingenuity the unique features of the Ultra CMOS process, using very high-linearity, high-speed transistors in combination with high Q indicators”. He added: “The LNA is an excellent example of collaboration between the rare and brilliant design skills of our group at La Trobe University, the domain expertise in radio astronomy at CSIRO, and a leading-edge technology process from Peregrine Semiconductor”.

After three months in design at La Trobe University’s Centre for Technology Infusion, Bundoora, the chip was fabricated at Peregrine’s foundries in Australia and the United States. It is now being put through its paces in performance testing at CSIRO’s ATNF facilities at Marsfield.

Andrew Brawley, Executive Director Peregrine Semiconductor Australia Pty Ltd and Dr Harris Lee accepting the EDN award. Photo Courtesy: EDN and Electronics News magazine.

Only stringent testing will reveal whether the actual performance of the LNA is as good as the design model. Buoyed by the results so far, the LNA team is now considering as its next project the design and implementation of a

fully integrated receiver system using the same advanced Peregrine process.

As Mr Andrew Brawley, Managing Director of Peregrine Semiconductor Australia notes, the LNA will not only serve as a prototype for developing a world-leading integrated receiver design but – because of its capacity to operate at milli-Kelvin temperatures – is also under test by the NSW Quantum Computing Project, a multi-million dollar research quest for a supercomputer that operates at near-zero temperatures.

Dr Carole Jackson, CSIRO ATNF Business Development Manager

Raman Research Institute, India, Joins Murchison Wide-field Array ConsortiumThe Murchison Wide-field Array (MWA) is a low-frequency demonstrator project with partner institutions in the US and Australia. The “Core System” of the MWA is being designed and fabricated to do key science projects such as the detection and mapping of the signal from the epoch of reionization, and remote sensing of the heliosphere. Given the proposed capabilities of MWA and the involvement of the Raman Research Institute (RRI), India, in the field of low frequency radio astronomy and instrumentation for several decades, there is a natural interest at RRI to participate in the MWA effort, and use the telescope to pursue several specific and general areas of research.

The general areas of interest that prompted RRI to consider joining the consortium are low frequency studies of pulsars, radio recombination lines, transient phenomenon and non-thermal polarized emission of the Galaxy. Some of these projects can be carried out with the planned core MWA system, while a few others need augmentation to increase the bandwidth beyond 32 MHz in the phased array mode. RRI’s proposal to join was accepted in December, 2006, and thus began the process of the RRI group’s getting integrated into the MWA team.

Presently RRI is actively participating in the design and development of receiver node for MWA tiles. RRI, in collaboration with the Research School of Astronomy and Astrophysics, ANU, Australia, CSIRO ATNF and ICT groups of CSIRO, Sydney, has put together a sub-system with two ADFB boards (16 ADC channels and Polyphase filter banks) and one data aggregation board without the fibre. The sub-system was tested at RRI using an in-house developed data acquisition board in burst mode. In this mode data with full bandwidth is acquired for one cycle time of the filter bank in any one burst. The system performance was found to be satisfactory. As this report is going to press a team of four engineers from RRI left

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Bangalore to join the ANU team to put together a complete receiver node including beam formers and signal conditioners and jointly make preparations for the next expedition to the Early Research Area (ERA) site in Western Australia.

The picture shows some of the RRI team members working for the receiver system at Bangalore. Anish and Somashekar (not in the picture) took part in a recent expedition to the ERA to install 32 tiles. Anish with Prabu, Srivani and Gopala Krishna will be participating in the testing/integration phase at ANU. From there Anish, Prabu and GK will also join the expedition team for the tests later this month in Western Australia.

On the science front RRI is developing software pipelines for analysing signals from the array configured in the phased array mode. The software can be used for analysing pulsar data and also for searching radio transients. A discussion to integrate this into the mainstream software has been initiated.

The RRI team working on the MWA receiver node. From Left to Right: Anish Roshi, MR Gopala Krishna, BS Girish, T Prabu, S Madhavi, PA Kamini, KS Srivani and C Vinutha. Photo Courtesy: Colin Lonsdale.

N Udaya Shankar, RRI, India, uday@rri.res.in

ALMA Project Provides “Lessons Learned” to ASKAPA recent visit to the Atacama Large Millimetre Array (ALMA) project in Chile has provided CSIRO ATNF’s Phil Crosby and Dave DeBoer with the opportunity to learn about construction of multi-antenna arrays in a harsh, remote location.

Guided by Tony Beasley, ALMA’s project manager, Dave and Phil took a ‘behind the scenes’ look at this impressive instrument being built in the Andes Mountains near San Pedro de Atacama.

ALMA will be composed of around 80 3 12 m antennas located at 5000 m elevation exploring the cold universe at wavelengths of 0.3 to 9.6 mm. The array will be controlled from a substantial Operational Support Facility at 2900 m.

The construction logistics, remote landscape, and international collaboration nature of ALMA makes for a useful analogue for ASKAP and the SKA, and the CSIRO ATNF delegation was permitted to observe construction management in close detail. Of particular interest was the Project Control Management System (PCMS) run out of ALMA’s Santiago office which supports the complex scheduling, budget control, reporting and change management processes. The integrated project schedule allows multiple tracking point monitoring and daily critical path reporting.

Whilst ALMA has many differences in terms of infrastructure, industry engagement and funding, much of what ALMA has implemented can be scaled down and incorporated in ASKAP as ‘best practice’ project management.

The ALMA ‘top site’ at 5000 m, looking from where the centre of the array will be. Photo Credit: Dave DeBoer.

Phil Crosby, CSIRO ATNF Business Strategist

New Operations Model for CSIRO ATNFIn order to achieve the overarching goal expressed in its Vision Statement, namely:

‘By 2012, the Australia Telescope National Facility (ATNF) will be operating four world-class observatories ensuring its continued status as a leading global contributor to the understanding of the universe’, the ATNF expects to begin implementing significant changes to the operation of its telescopes (subject to feedback from the ATNF Steering Committee after its December meeting).

The changes have three principal motives:

to achieve the Decadal Plan strategy of operating four world-class radio telescopes in 2012 while minimising the need for additional continuing resources;

to establish integrated and scalable practices and structures to position CSIRO and Australia for the SKA;

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to build on existing operational differentiators that have been beneficial to Australian radio astronomy.

The key elements of the planned changes are to establish integrated operations of all four ATNF telescopes, through:

1. Restructuring into Science Operations and Engineering Operation;

2. Establishing a Science Operations Centre (SOC) at a central location – initially Marsfield;

3. Streamlining supported modes according to scientific priorities.

The ATNF is about to appoint key staff to lead Science Operations and Engineering Operations and then begin to establish functional groups that will replace the current regional or observatory-based groups. The user-operator model where astronomers control ATNF telescopes for their own observations will continue to be the usual mode of operation – except for ASKAP which will operate as a data pipeline with astronomers interacting with the data archive. Once the Science Operations Centre (SOC) is completely established, fully supported observing will be available only from the SOC. Observing from the observatories themselves will be possible when necessary, and remote observing from sites other than the SOC will be possible for the ATCA (Australia Telescope Compact Array at Narrabri), Mopra and Parkes. The range of instrumentation, supported observing modes, scheduling and support will be streamlined to balance cost against scientific impact.

Lewis Ball, CSIRO ATNF Deputy Director

Murchison Radio-astronomy Observatory’s Proposed Accommodation UpgradeThe scientific community will welcome the ongoing refurbishment of proposed staff accommodation for the Murchison Radio-astronomy Observatory (MRO). In close consultation with regional architects the MRO’s existing heritage-listed cottages are to receive a much needed upgrade.

The renovations will include the installation of insulation, reverse cycle air-conditioning and flyscreens. An internal fit-out will provide new kitchens, lounges dining rooms and bathrooms, as well as new furniture, flooring and curtains. A new gazebo, barbeque and lawn area is also proposed to make the most of the Mid West’s hot summer nights.

The work is being coordinated by Western Australia’s Department of Industry and Resources (DoIR) and is expected to be completed by June 2008.

Daniela Mattheys, General Manager – Project Coordination, Radio Astronomy, and Norelle O’Neill, Senior Project Officer – Communications, Radio Astronomy Project

Radio Astronomy Appointments at Curtin University of TechnologyLast month the Vice Chancellor of Curtin University of Technology (Perth), Professor Jeanette Hacket, had the pleasure of introducing two new appointees, Professor Steven Tingay and Professor Peter Hall, to both industry and staff representatives at Curtin University.

From Left to Right: Prof Peter Hall, Mr Charlie Thorn (Associate Director, Research and Development) and Prof Steven Tingay.

Professor Hall was the International Project Engineer for the SKA project and is currently back in Australia working with CSIRO. Professor Hall has been appointed Professor of Radio Astronomy Engineering in Curtin’s School of Engineering and will take up this position in July 2008.

Professor Hall is Chair of the Engineering Working Group for the SKA and a principal author of the successful European SKA Preparatory Phase proposal, to which the Curtin team will contribute significantly by way of the Murchison Widefield Array project.

In his brief address to those present, Professor Hall spoke of the role he had played as International Project Engineer, in technical and policy developments in relation to the SKA project. He elaborated on the broader implications of either Australia or Southern Africa securing the bid. He also spoke of the important role that Curtin has been playing in providing operational and technical support to so called ‘pathfinder project’ groups working in the Murchison. Professor Hall will spearhead the further development of this Curtin role.

Professor Tingay was recruited to Curtin’s School of Science and Computing, as Professor of Radio Astronomy in the Department of Imaging and Applied Physics in mid 2007. He was previously at Swinburne University and is a world renowned radio astronomer, and has played an integral role in developing the collaboration between partner countries in order to fortify Australia’s SKA project bid.

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Professor Tingay, who is an expert in high-performance software correlators for VLBI (Very Long Baseline Interferometry) techniques, spoke about the computational infrastructure and resources required to collate data from linked radio telescopes. His ongoing work at Curtin will be aided by access to a new level of high-performance computing being installed at the IVEC supercomputer facility at Perth’s Technology Park.

The SKA is an extremely important large scale science project in the radio astronomy area, which has been flagged by the State’s Chief Scientist Lyn Beazley as ‘top priority’ for WA Science. Professor Tingay and Professor Hall will provide great leadership at Curtin in this very exciting area.

Reproduced by kind permission of the Office of the Vice Chancellor, Curtin University of Technology

Australian SKA Planning Office (ASPO) Hands “Baton” to ASCCWith the formation of the intergovernmental Australian SKA Coordination Committee to promote and coordinate Australia’s SKA activities (see report in auSKA Newsletter 14), the Australian SKA Planning Office at CSIRO ATNF has now closed. The ASPO team marked the event with a pizza and champagne lunch, celebrating ASPO’s many achievements. These include the compilation and submission of the Australasian SKA site bid, progression of the Radio-Quiet Zone in WA, and the publication of papers, newsletters, fact sheets and websites that have kept the wider community informed about Australia’s SKA activities. ASPO was also involved in organising national and international SKA meetings, was the point of contact with ISPO, and facilitated enhanced industry engagement in the SKA in Australia. Well done ASPO team! Regular readers of these newsletters will have noticed that the ASPO Newsletters have transformed into the auSKA Newsletters. CSIRO ATNF is still responsible for production of the newsletters.

News from the Australian SKA Coordination Committee – Australia to Host the Second International SKA ForumAt the 8 October 2007 meeting of the SKA Funding Agencies Group in Manchester, it was agreed that the second International SKA Forum would be held in Perth in 2008. It was also agreed that the third Forum would be held in South Africa in 2009.

The Forum will be held in early April (tentatively on 4 April 2008, but exact date to be confirmed) around the time of several other major international SKA meetings in Perth. These include the Deep Surveys of the Radio Universe with SKA Pathfinders conference and meetings of the Funding Agencies Group and the SKA Science and Engineering Committee.

The Australian SKA Coordination Committee (ASCC) is currently making arrangements for the Forum, which will feature a varied program of speakers and discussions on the key science, technical and policy issues for the SKA project. Arrangements for the Forum were discussed at the last ASCC meeting, held in Sydney on October 24. Potential venues were inspected by ASCC agency staff in late November 2007. The ASCC Communications and Stakeholder Management Working Group and the Observatory Governance Working Group also met during this latest visit. The next meeting of the ASCC will be held in December 2007.

The Forum will be an excellent opportunity for astronomers, engineers and policy makers with SKA interests from around the world to catch up on the latest developments and contribute to moving the project into its next phase. An international Forum Reference Group is currently being established to assist the organisers. Further information on the Forum will be provided in subsequent editions of the auSKA newsletter and on the Australian SKA website www.ska.gov.au.

The ASCC is continuing to work towards the permanent establishment of the Murchison Radio-astronomy Observatory (MRO) and protection of the outstanding radio-quiet qualities of the site. This work will build on the CSIRO Early Research Area, already established at the MRO site, and the Australian Communications and Media Authority (ACMA) Radiocommunications Assignment Licensing Instruction, which created the Mid-West Radio Quiet Zone.

The ASCC is also working with the National Centre for Science and Technology (Questacon) and Scitech in Western Australia to develop an innovative education and public outreach program on the SKA. The program is being developed with a $350,000 grant from the Australian Government.

Following the recent Federal election in Australia, and subsequent change of Government, the SKA responsibilities of the former Department of Education, Science and Training have been transferred to the new Department of Innovation, Industry, Science and Research under the Minister for Innovation, Industry, Science and Research, Senator Kim Carr.

The latest announcements from the ASCC will continue to be available from the Australian SKA website at www.ska.gov.au

ASCC Secretariat

For more information contact:Diana LondishEmail: Diana.Londish@csiro.auPhone: +61 2 9372 4263www.ska.gov.au

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