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716 Annual Report For Annual Report 2000 AUSTRALIA TELESCOPE NATIONAL FACILITY ANNUAL REPORT 2000 ISSN 1038-9954 This is the report of the Steering Committee of the CSIRO Australia Telescope National Facility for the calendar year 2000. DESIGN Photograph Angela Finney, Art When You Need It © CSIRO Contents overview page 4 performance indicators page 12 science highlights page 16 operations page 38 3 observatory reports page 48 technology developments page 60 appendices page 70 Overview Science highlights in brief from sensitive observations taken with the Parkes radio telescope. First millimetre light for upgraded Australia Telescope page 16 A very young pulsar discovered in the Parkes Multibeam Pulsar Survey page 24 After three years of designing, building and testing, first light at millimetre In the past four years, the Parkes radio wavelengths for the upgraded Australia telescope and its multibeam receiver have Telescope Compact Array occurred on 30 been used to scan the Milky Way for November 2000. Two of the six antennas pulsars. The Parkes survey has nearly were fitted with the new 3-mm receiving doubled the number of known pulsars. systems and were used to observe silicon Among the discoveries is the pulsar J1119- monoxide maser emission from the Orion 6127 which rotates just over twice per nebula. second. Its spin parameters show that it is only 1,600 years old, making it the fourth Massive proto-planetary disks detected at youngest pulsar known in the Milky Way. radio wavelengths page 18 Observations taken with the Australia Observations taken with the Australia Telescope Compact Array show that the Telescope Compact Array reveal the pulsar is at the centre of a previously presence of three sources in the starburst uncatalogued supernova remnant. cluster NGC 3603, identified as proto- A new test for general relativity page 26 planetary disks on images from the Hubble Space Telescope and the ESO Very Large A team of Australian and US astronomers Telescope. The radio sources are 20–30 have used the Parkes radio telescope to times larger than their counterparts in the measure the distortion of space-time near Orion nebula and are much brighter than a star 140 parsecs from Earth, confirming a expected. prediction of Einstein’s general theory of relativity. They measured the arrival times New discoveries of millisecond pulsars in of the pulses received on Earth from the globular clusters page 20 4 bright millisecond pulsar, PSR J0437-4715, Globular clusters are a rich source of to within a tenth of a millionth of a second. millisecond pulsars. These are compact The HI environment of superbubbles in the neutron stars in binary systems that have Large Magellanic Cloud page 28 been “spun up” by mass accretion from the companion stars. In a study of 60 globular One of the most important processes that clusters, ten new millisecond pulsars have drives the evolution of galaxies is the been discovered in four clusters which injection of energy into the interstellar were not previously known to contain medium from the winds and supernova pulsars. The new discoveries were made explosions of massive stars. In starburst Photograph Photograph © CSIRO © S Amy Overview regions, groups of massive stars may blow millions of light years. Observations taken “superbubbles” of hot ionized gas which with the Australia Telescope Compact extend over large distances. A team of Array for the giant radio galaxy B0114-476 researchers has used the Australia reveal a “double-double” structure with Telescope Compact Array to study the two outer diffuse lobes and two inner jet- neutral hydrogen environment around like features. Such a structure suggests that three young superbubbles in the Large the galaxy may experience recurrent Magellanic Cloud. They find that while the nuclear activity. ionized gas shells are similar for the three The gaseous halos of three spiral galaxies regions, the neutral hydrogen distributions page 36 are strikingly different. Observations of three southern edge-on The HIPASS Bright Galaxy Survey page 30 spiral galaxies, taken with the Australia The HI Parkes All-Sky Survey has provided Telescope Compact Array, show that the the first ever survey of extragalactic neutral galaxies have extended gaseous halos. The hydrogen over the southern sky. The radio emission occurs from relativistic survey was completed in March 2000 and electrons which are released during the data were released in May 2000. One of multiple supernova explosions. The radio the first survey products is the HIPASS data provide new insights into the star Bright Galaxy Catalogue, a catalogue of formation history of the observed galaxies. the 1,000 brightest HI galaxies in the southern hemisphere. Technology highlights HIPASS turns up new gas in the NGC 2442 in brief group page 32 MNRF Upgrades The HI Parkes All Sky Survey has revealed First results at 3 mm page 16 a huge cloud of neutral hydrogen gas, near A major milestone was reached in the bright spiral galaxy NGC 2442. The gas November 2000 with the first 3-mm cloud, designated J0731-69, contains a observations of the upgraded Australia 5 thousand-million solar masses of hydrogen Telescope Compact Array, taken using two but shows no evidence for any stars or star antennas. The success of the millimetre formation activity. The cloud may have observations highlights the excellence of been torn out of NGC 2442 during a tidal the MNRF engineering. interaction with another galaxy. Australia Telescope Compact Array local Recurrent activity in giant radio galaxies oscillator distribution page 62 page 34 Almost all of the optical fibres for the local Giant radio galaxies have linear sizes of oscillator distribution network have been Overview laid between the Control Room and the of using spherical refracting antennas antenna station posts. (Luneburg lenses) for the Square Extra stations and the north spur page 63 Kilometre Array. Civil engineering works associated with Interference Mitigation page 67 four new stations on the east-west track and The ATNF has developed successful new five new stations on the north spur of the techniques for the removal of interference Australia Telescope Compact Array were signals from correlated radio astronomy completed in 2000. data. MMICS page 64 SKA site testing page 69 Monolithic microwave integrated circuits Work has continued to identify possible (MMICs) are an essential component of sites for the SKA in Australia and the the high-frequency receiver upgrades. feasibility of establishing a radio-quiet After bonding and packaging, 3-mm and reserve. 12-mm indium phosphide MMICs were retrofitted to two prototype receivers on The ATNF in Brief the Australia Telescope Compact Array. Both the system temperatures and The Australia Telescope National Facility bandwidths achieved were outstanding. (ATNF) supports Australia’s research in radio astronomy, one of the major fields of High-speed two-bit sampler page 64 modern astronomy, by operating the Considerable progress was made with the Australia Telescope, a set of eight development of a high-speed two-bit individual radio telescopes. digitiser using indium phosphide Mission heterojunction bipolar transistor (InP HBT) technology. This is designed to • To operate and develop the Australia sample astronomical signals at up to eight Telescope as a national research Gigabits per second. facility for use by Australian and 6 international researchers. InP HBT technology was also used to develop a digitiser with integrated photo- • To exploit the telescope’s unique receiver circuits which allow the digitiser’s southern location and technological output to be passed to optical fibres via advantages to maintain its position externally bonded laser diodes. as a world-class radio astronomy The Square Kilometre Array observatory. Antennas for the SKA page 67 • To further the advancement of knowledge. Work continued on assessing the feasibility Overview Size and funding In 2000 the telescopes were used by: The ATNF employs 135 staff. In 1999–2000 38 researchers from the ATNF; the organization’s total funding was 77 researchers from 16 other Australian $16.64M, of which $12.23M was direct institutions; and appropriation from CSIRO. 243 researchers from 98 institutions in Status within CSIRO 23 overseas countries. The Australia Telescope National Facility is The ATNF in the Australian context managed as a National Facility by The ATNF is the largest single Australia’s largest national research astronomical institution in Australia. institution, CSIRO. Formerly part of the Ninety per cent of Australian radio CSIRO Division of Radiophysics, it became astronomy is carried out through the a separate Division in January 1989. The ATNF. The organization has strong links Australia Telescope Steering Committee, with its primary user base, the university appointed by the Minister for Science to community; the interests of telescope users advise the ATNF Director, also acts as the are represented by the Australia Telescope Advisory Committee for CSIRO’s Radio Users Committee. Astronomy Sector. The ATNF’s Sydney headquarters are co- Status as a National Facility located with those of the Anglo-Australian The ATNF became a National Facility in Observatory, an independent bi-national April 1990. As a National Facility, the facility that provides world-class optical Australia Telescope provides world-class and infrared facilities. This close observing facilities in radio astronomy for association is unique, in world terms, and astronomers at Australian and overseas promotes
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