42 research outputs found

    The PULSE@Parkes project: A new observing technique for long-term pulsar monitoring

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    The PULSE@Parkes project has been designed to monitor the rotation of radio pulsars over time spans of days to years. The observations are obtained using the Parkes 64-m and 12-m radio telescopes by Australian and international high school students. These students learn the basis of radio astronomy and undertake small projects with their observations. The data are fully calibrated and obtained with the state-of-the-art pulsar hardware available at Parkes. The final data sets are archived and are currently being used to carry out studies of 1) pulsar glitches, 2) timing noise, 3) pulse profile stability over long time scales and 4) the extreme nulling phenomenon. The data are also included in other projects such as gamma-ray observatory support and for the Parkes Pulsar Timing Array project. In this paper we describe the current status of the project and present the first scientific results from the Parkes 12-m radio telescope. We emphasise that this project offers a straightforward means to enthuse high school students and the general public about radio astronomy while obtaining scientifically valuable data sets.Comment: accepted for publication by PAS

    The Parkes Observatory Pulsar Data Archive

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    The Parkes pulsar data archive currently provides access to 144044 data files obtained from observations carried out at the Parkes observatory since the year 1991. Around 10^5 files are from surveys of the sky, the remainder are observations of 775 individual pulsars and their corresponding calibration signals. Survey observations are included from the Parkes 70cm and the Swinburne Intermediate Latitude surveys. Individual pulsar observations are included from young pulsar timing projects, the Parkes Pulsar Timing Array and from the PULSE@Parkes outreach program. The data files and access methods are compatible with Virtual Observatory protocols. This paper describes the data currently stored in the archive and presents ways in which these data can be searched and downloaded.Comment: Accepted by PAS

    Radio Galaxy Zoo: host galaxies and radio morphologies derived from visual inspection

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    We present results from the first 12 months of operation of Radio Galaxy Zoo, which upon completion will enable visual inspection of over 170000 radio sources to determine the host galaxy of the radio emission and the radio morphology. Radio Galaxy Zoo uses 1.4 GHz radio images from both the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) and the Australia Telescope Large Area Survey (ATLAS) in combination with mid-infrared images at 3.4 μm from the Wide-field Infrared Survey Explorer (WISE) and at 3.6 μm from the Spitzer Space Telescope. We present the early analysis of the WISE mid-infrared colours of the host galaxies. For images in which there is >75 per cent consensus among the Radio Galaxy Zoo cross-identifications, the project participants are as effective as the science experts at identifying the host galaxies. The majority of the identified host galaxies reside in the mid-infrared colour space dominated by elliptical galaxies, quasi-stellar objects and luminous infrared radio galaxies. We also find a distinct population of Radio Galaxy Zoo host galaxies residing in a redder mid-infrared colour space consisting of star-forming galaxies and/or dust-enhanced non-star-forming galaxies consistent with a scenario of merger-driven active galactic nuclei (AGN) formation. The completion of the full Radio Galaxy Zoo project will measure the relative populations of these hosts as a function of radio morphology and power while providing an avenue for the identification of rare and extreme radio structures. Currently, we are investigating candidates for radio galaxies with extreme morphologies, such as giant radio galaxies, late-type host galaxies with extended radio emission and hybrid morphology radio source

    Radio Galaxy Zoo:host galaxies and radio morphologies derived from visual inspection

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    We present results from the first 12 months of operation of Radio Galaxy Zoo, which upon completion will enable visual inspection of over 170 000 radio sources to determine the host galaxy of the radio emission and the radio morphology. Radio Galaxy Zoo uses 1.4 GHz radio images from both the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) and the Australia Telescope Large Area Survey (ATLAS) in combination with mid-infrared images at 3.4 μm from the Wide-field Infrared Survey Explorer (WISE) and at 3.6 μm from the Spitzer Space Telescope. We present the early analysis of the WISE mid-infrared colours of the host galaxies. For images in which there is >75 per cent consensus among the Radio Galaxy Zoo cross-identifications, the project participants are as effective as the science experts at identifying the host galaxies. The majority of the identified host galaxies reside in the mid-infrared colour space dominated by elliptical galaxies, quasi-stellar objects and luminous infrared radio galaxies. We also find a distinct population of Radio Galaxy Zoo host galaxies residing in a redder mid-infrared colour space consisting of star-forming galaxies and/or dust-enhanced non-star-forming galaxies consistent with a scenario of merger-driven active galactic nuclei (AGN) formation. The completion of the full Radio Galaxy Zoo project will measure the relative populations of these hosts as a function of radio morphology and power while providing an avenue for the identification of rare and extreme radio structures. Currently, we are investigating candidates for radio galaxies with extreme morphologies, such as giant radio galaxies, late-type host galaxies with extended radio emission and hybrid morphology radio sources

    Recent Finance Advances in Information Technology for Inclusive Development: A Survey

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    Reproductive Efficiency of Purebred and Crossbred Dairy Cattle

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    Nine measures related to breeding efficiency were used for comparisons among purebred Ayrshires, Brown Swiss, Holsteins, and Jerseys and between purebreds and 32 crossbred groups representing 2-breed, 3-breed, 5/8, and backcrosses by purebred sires and progeny of crossbred sires. There were four herds with Holsteins common to all, Brown Swiss and Jerseys in three herds and Ayrshires in one herd. Four 2-breed, two 3-breed, and two backcross groups were common to two or more herds. Among purebreds, breed effects were significant in 16 of 72 tests, but there was no consistent trend favoring one breed. Generally, Jerseys were better than Holsteins, and Brown Swiss were poorer than Holsteins. Purebred females bred to their breed required similar services for conception (1.77 versus 1.79) as when bred to a different breed of sire. Least squares estimates of differences between purebreds and crossbreds favored crossbreds in 86 of 144 tests suggesting advantages for breeding efficiency; however, few were significant. Standard errors frequently exceeded estimates of differences. Parity was not associated with superiority in the crosses

    Disparities in Infant Health Among American Indians and Alaska Natives in US Metropolitan Areas

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    Abstract available at publisher's website.http://dx.doi.org/10.1542/peds.109.4.62

    The development of auditory comprehension in children after receiving a cochlear multiple-channel implant

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    This is a publisher’s version of an abstract from the Annual General and Scientific Meeting of the Australian Society of Otolaryngology Head and Neck Surgery, 1992. This version is reproduced with permission from Australian Society of Otolaryngology Head and Neck Surgery.Since late 1989, half the cochlear implant patients at the Royal Victorian Eye and Ear Hospital have been young children. There is a gradual improvement of auditory comprehension in most cases using the criteria of environmental sound detection, as well as, prosody, high frequency phoneme and word discrimination. The rate of improvement and final result depend on the duration of deafness, presence of residual hearing, and quality of auditory-oral habilitation. Younger children usually progress more quickly than older children. Some adolescents who use Total Communication and who have no residual hearing, achieve assistance with lipreading. Children with Usher's Syndrome should be actively encouraged to participate in auditory-oral habilitation should they become totally deaf or blind
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