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MOPS Installation at Mopra and First Light ATNF News Issue No. 59, June 2006 ISSN 1323-6326 FEATURES IN THIS MOPS installation at Mopra and first light ISSUE As we enter the 2006 millimetre at Mopra, particularly as a wide observing season at the ATNF, the bandwidth backend for the new MOPS installation at Mopra and first light installation of the ATNF’s newest and Monolithic Millimetre-wave Integrated Page 1 most versatile spectrometer is now Circuit (MMIC) based millimetre complete. The MOPra Spectrometer receiver. It is not only in the signal (MOPS) recently completed the final SKA and xNTD news processing area where MOPS has stages of testing on the Mopra “borrowed” from other ATNF Page 3 millimetre telescope and observations development projects. The system used have commenced for 2006, with to transmit the 8 GHz bandwidth signals A new neutron star relativistic jet source fascinating results already being over fibre optic cables from the vertex in the Galaxy produced. ATNF engineers have room to the control building was Page 7 produced a frequency-agile originally developed by Mark Leach for spectrometer system that will become the wideband analogue correlator at the ASAP – ATNF Spectral the envy of millimetre astronomers Compact Array. The 4 Gigasample/sec Analysis Package worldwide. So much so, that the 2006 samplers used in MOPS were originally Page 8 winter season at Mopra was already developed by Paul Roberts for the over-subscribed well before the fully wideband pulsar correlator at Parkes. 2006 Grote Reber functioning and operational system was They use an indium phosphide MMIC 2- Gold Medal even announced! bit digitiser designed by Paul as part of a awarded to Bernard CSIRO Executive Special Project, the Yarnton Mills The spectrometer same project which saw the Page 9 development of the indium phosphide MOPS is largely a by-product of the MMIC low-noise amplifiers (LNAs) Worth the wait ... development being undertaken for the used in the Compact Array and Mopra registration opens for the Synthesis Compact Array Broadband Backend 12- and 3-mm receivers. Imaging School (CABB) upgrade project. The CABB Page 10 project, part of the Major National The MOPS signal processing hardware Research Facility (MNRF) program, comprises four large circuit boards, one Jon Ables aims to develop signal processing for each 2 GHz quadrant of the total 8 1937 – 2006 technologies relevant to the SKA, and to GHz MOPS bandwidth. The boards, Page 11 demonstrate them in a new backend for which were designed and produced by the Compact Array. It is these same Dick Ferris and Evan Davis, were Pulsars, magnetars signal processing technologies which developed as prototypes for the CABB and RRATs have been applied to MOPS. Funding system. They are by any measure the Page 13 for MOPS came from an ARC LIEF most complex Printed Circuit Boards (Australian Research Council Linkage (PCBs) yet produced at the ATNF, each Investigating grain Infrastructure Equipment and Facilities) containing seventeen large field growth in southern grant to a consortium of universities, led programmable gate arrays (FPGAs), protoplanetary disks by the University of New South Wales which provide the processing power Page 18 (UNSW), and the ATNF. It was the required. Other vital statistics of the UNSW astronomers, led by Michael boards are: 19 layers, 30,000 pads and Burton, who originally realised the 140,000 track segments. The signal potential of applying the CABB developments to single dish applications Continued on page 16 Editorial Welcome to the June 2006 edition of the ATNF Phillips and Malte Marquarding. Dave McConnell News. introduces to you the new Narrabri Officer-in- Charge, Phil Edwards. The regular Observatory This issue is again filled with articles and news items reports include Phil’s first contribution for the on activities happening at the ATNF. Thank you to Compact Array and Mopra. all our contributors! Dave Jauncey has contributed a news item about the Our cover article, from Warwick Wilson, Erik Muller 2006 Grote Reber Gold Medal being awarded to one and Dick Ferris, is about the installation of and first of the great pioneers of radio astronomy, Bernie light observations with MOPS, the new frequency- Mills. Sadly, we also report the passing of one of the agile, wideband spectrometer for the Mopra greats of the CSIRO and radio astronomy in general, telescope. This issue also reports on the first light Jon Ables. from the NTD antennas and other NTD, xNTD and SKA news. Note that registration is open for the Narrabri Synthesis Imaging School; for details see Ilana As usual we have several science articles. Sarah Klamer’s news item. Maddison and her collaborators contribute new insights into grain growth in proto-planetary disks. We hope you enjoy the newsletter! As always your There is, once again, exciting news about pulsars, comments and suggestions are welcome. The web magnetars and RRATs, as presented by Dick version of this and previous issues can be found at Manchester. Compact Array results of another www.atnf.csiro.au/news/newsletter. interesting variable radio-emitting source, the newly discovered “Z” source J1701–462, is described by Michael Dahlem, Jessica Chapman and Rob Fender et. al. Joanne Houldsworth The ATNF Newsletter Production Team In other news, information about the ATNF Spectral ([email protected]) Analysis Package (ASAP) is brought to you by Chris Contents MOPS installation at Mopra and first light............................................................................................... 1 SKA and xNTD news ............................................................................................................................. 3 A new neutron star relativistic jet source in the Galaxy .......................................................................... 7 ASAP – ATNF Spectral Analysis Package ............................................................................................. 8 2006 Grote Reber Gold Medal awarded to Bernard Yarnton Mills ......................................................... 9 New Narrabri Officer-in-Charge .......................................................................................................... 10 Worth the wait ... registration opens for the Synthesis Imaging School ................................................ 10 Jon Ables 1937 – 2006 ............................................................................................................................11 Pulsars, magnetars and RRATs ............................................................................................................. 13 Investigating grain growth in southern protoplanetary disks .................................................................. 18 ATNF outreach ...................................................................................................................................... 22 Parkes observatory report ..................................................................................................................... 24 Compact Array and Mopra report ......................................................................................................... 25 Time assignment information ................................................................................................................. 28 ATNF publications list ............................................................................................................................ 30 Page 2 ATNF News, Issue No. 59, June 2006 News SKA and xNTD news First light for NTD antenna On the afternoon of Friday 21 April 2006, the L-shaped receiver in the primary focus. An uncooled eastern New Technology Demonstrator (NTD) low-noise amplifier (LNA) sends the signal from a antenna on the Marsfield antenna range saw its single feed to the antenna’s pedestal, where it is “first light”, successfully detecting the Orion Nebula. mixed down to a few tens of megahertz in two stages. Initial tests were performed using the Over the past few months the antennas have been unmodulated beacon of a geo-stationary satellite, assembled and a new reflector surface (6 mm x Optus B1, with a transmitter positioned on the grass 6 mm mesh) installed. The original gear trains were near the antenna. The Orion Nebula was then retained, but new drive and control systems were successfully detected with cross-scans, using needed. The eastern antenna now has a simple approximately 10 MHz of bandwidth (Figure 1). Figure 1: The upper panel shows the power measured at the conversion chain output as a function of time, and the lower panel shows the antenna offset in declination at the same time. The Orion Nebula is clearly detected during two scans at 6.55 h and 6.59 h. Page 3 News Future work includes determining the pointing model, • xNTD System Design, Integration and accurately measuring the focus and measuring the Infrastructure; far-field reception pattern of the antenna. The • NTD; procedure will have to be repeated for the western • xNTD Antennas and Control; antenna, before experiments can begin with a focal- • xNTD Smart Feeds; plane array in one dish and a single-feed receiver in • xNTD Digital Systems; the other. • xNTD Receivers; • xNTD Computing; and Enno Middelberg and Mike Kesteven ([email protected]) • xNTD Signalling and Data Transport. Antenna feeds The Australian SKA Project Office (ASPO) project will also be incorporated into the theme. Our main tasks now in the NTD project are to fur- Draft plans for this structure have been submitted to ther
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