Browsing by Author "Lenc, E."

Now showing items 1-20 of 27

    • An analysis of the halo and relic radio emission from Abell 3376 from Murchison Widefield Array observations 

      George, Lijo T.; Dwarakanath, K. S.; Johnston-Hollitt, M.; Hurley-Walker, N.; Hindson, L.; Kapińska, A. D.; Tingay, S. J.; Bell, M.; Callingham, J. R.; For, Bi-Qing; Hancock, P. J.; Lenc, E.; McKinley, B.; Morgan, J.; Offringa, A.; Procopio, P.; Staveley-Smith, L.; Wayth, R. B.; Wu, Chen; Zheng, Q.; Bernardi, G.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Corey, B. E.; Deshpande, A. A.; Emrich, D.; Goeke, R.; Greenhill, L. J.; Hazelton, B. J.; Kaplan, D. L.; Kasper, J. C.; Kratzenberg, E.; Lonsdale, C. J.; Lynch, M. J.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Ord, S. M.; Prabu, T.; Rogers, A. E. E.; Roshi, A.; Shankar, N. Udaya; Srivani, K. S.; Subrahmanyan, R.; Waterson, M.; Whitney, R. L. Webster A. R.; Williams, A.; Williams, C. L. (2015-08-21)
      We have carried out multiwavelength observations of the near-by ($z=0.046$) rich, merging galaxy cluster Abell 3376 with the Murchison Widefield Array (MWA). As a part of the GaLactic and Extragalactic All-sky MWA survey ...

    • The Australia Telescope Compact Array Broad-band Backend: description and first results 

      Wilson, Warwick E.; Ferris, R. H.; Axtens, P.; Brown, A.; Davis, E.; Hampson, G.; Leach, M.; Roberts, P.; Saunders, S.; Koribalski, B. S.; Caswell, J. L.; Lenc, E.; Stevens, J.; Voronkov, M. A.; Wieringa, M. H.; Brooks, K.; Edwards, P. G.; Ekers, R. D.; Emonts, B.; Hindson, L.; Johnston, S.; Maddison, S. T.; Mahony, E. K.; Malu, S. S.; Massardi, M.; Mao, M. Y.; McConnell, D.; Norris, R. P.; Schnitzeler, D.; Subrahmanyan, R.; Urquhart, J. S.; Thompson, Mark; Wark, R. M. (2011-09)
      Here, we describe the Compact Array Broad-band Backend (CABB) and present first results obtained with the upgraded Australia Telescope Compact Array (ATCA). The 16-fold increase in observing bandwidth, from 2 x 128 to 2 x ...

    • Broadband Spectral Modeling of the Extreme Gigahertz-Peaked Spectrum Radio Source PKS B0008-421 

      Callingham, J. R.; Gaensler, B. M.; Ekers, R. D.; Tingay, S. J.; Wayth, R. B.; Morgan, J.; Bernardi, G.; Bell, M. E.; Bhat, R.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Deshpande, A. A.; Ewall-Wice, A.; Feng, L.; Greenhill, L. J.; Hazelton, B. J.; Hindson, L.; Hurley-Walker, N.; Jacobs, D. C.; Johnston-Hollitt, M.; Kaplan, D. L.; Kudrayavtseva, N.; Lenc, E.; Lonsdale, C. J.; McKinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Offringa, A. R.; Ord, S. M.; Pindor, B.; Prabu, T.; Procopio, P.; Riding, J.; Srivani, K. S.; Subrahmanyan, R.; Shankar, N. Udaya; Webster, R. L.; Williams, A.; Williams, C. L. (2015-08-20)
      We present broadband observations and spectral modeling of PKS B0008-421, and identify it as an extreme gigahertz-peaked spectrum (GPS) source. PKS B0008-421 is characterized by the steepest known spectral slope below the ...

    • Calibration and Stokes Imaging with Full Embedded Element Primary Beam Model for the Murchison Widefield Array 

      Sokolowski, M.; Colegate, T.; Sutinjo, A. T.; Ung, D.; Wayth, R. B.; Hurley-Walker, N.; Lenc, E.; Pindor, B.; Morgan, J.; Kaplan, David L.; Bell, M. E.; Callingham, J. R.; Dwarakanath, K. S.; For, Bi-Qing; Gaensler, B. M.; Hancock, P. J.; Hindson, L.; Johnston-Hollitt, M.; Kapińska, A. D.; McKinley, B.; Offringa, A. R.; Procopio, P.; Staveley-Smith, L.; Wu, C.; Zheng, Q. (2017-11-27)
      The Murchison Widefield Array (MWA), located in Western Australia, is one of the low-frequency precursors of the international Square Kilometre Array (SKA) project. In addition to pursuing its own ambitious science program, ...

    • Deep Chandra observations of Pictor A 

      Hardcastle, M. J.; Lenc, E.; Birkinshaw, M.; Croston, J. H.; Goodger, J. L.; Marshall, H. L.; Perlman, E. S.; Siemiginowska, A.; Stawarz, L.; Worrall, D. M. (2016-02-01)
      We report on deep Chandra observations of the nearby broad-line radio galaxy Pictor A, which we combine with new Australia Telescope Compact Array (ATCA) observations. The new X-ray data have a factor 4 more exposure than ...

    • EMU : Evolutionary Map of the Universe 

      Norris, Ray P.; Hopkins, A. M.; Afonso, J.; Brown, S.; Condon, J. J.; Dunne, L.; Feain, I.; Hollow, R.; Jarvis, M.J.; Johnston-Hollitt, M.; Lenc, E.; Middelberg, E.; Padovani, P.; Prandoni, I.; Rudnick, L.; Seymour, N.; Umana, G.; Andernach, H.; Alexander, D. M.; Appleton, P. N.; Bacon, D.; Banfield, J.; Becker, W.; Brown, M. J. I.; Ciliegi, P.; Jackson, C.; Eales, S.; Edge, A. C.; Gaensler, B. M.; Giovannini, G.; Hales, C. A.; Hancock, P.; Huynh, M. T.; Ibar, E.; Ivison, R. J.; Kennicutt, R.; Kimball, Amy E.; Koekemoer, A. M.; Koribalski, B. S.; Lopez-Sanchez, A. R.; Mao, M. Y.; Murphy, T.; Messias, H.; Pimbblet, K. A.; Raccanelli, A.; Randall, K. E.; Reiprich, T. H.; Roseboom, I. G.; Roettgering, H.; Saikia, D. J.; Sharp, R. G.; Slee, O. B.; Smail, Ian; Thompson, Mark; Urquhart, J. S.; Wall, J. V.; Zhao, G. -B. (2011)
      EMU is a wide-field radio continuum survey planned for the new Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The primary goal of EMU is to make a deep (rms ~ 10 microJy/beam) radio continuum survey of the ...

    • Extragalactic Peaked-Spectrum Radio Sources at Low Frequencies 

      Callingham, J. R.; Ekers, R. D.; Gaensler, B. M.; Line, J. L. B.; Hurley-Walker, N.; Sadler, E. M.; Tingay, S. J.; Hancock, P. J.; Bell, M. E.; Dwarakanath, K. S.; For, B. -Q.; Franzen, T. M. O.; Hindson, Luke; Johnston-Hollitt, M.; Kapinska, A. D.; Lenc, E.; McKinley, B.; Morgan, J.; Offringa, A. R.; Procopio, P.; Staveley-Smith, L.; Wayth, R. B.; Wu, C.; Zheng, Q. (2017-02-20)
      We present a sample of 1,483 sources that display spectral peaks between 72 MHz and 1.4 GHz, selected from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey. The GLEAM survey is the widest ...

    • The first Murchison Widefield Array low frequency radio observations of cluster scale non-thermal emission : the case of Abell 3667 

      Hindson, L.; Johnston-Hollitt, M.; Hurley-Walker, N.; Buckley, K.; Morgan, J.; Carretti, E.; Dwarakanath, K. S.; Bell, M.; Bernardi, G.; Bhat, N. D. R.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Corey, B. E.; Deshpande, A. A.; Emrich, D.; Ewall-Wice, A.; Feng, L.; Gaensler, B. M.; Goeke, R.; Greenhill, L. J.; Hazelton, B. J.; Jacobs, D.; Kaplan, D. L.; Kasper, J. C.; Kratzenberg, E.; Kudryavtseva, N.; Lenc, E.; Lonsdale, C. J.; Lynch, M. J.; McWhirter, S. R.; McKinley, B.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Ord, S. M.; Pindor, B.; Prabu, T.; Procopio, P.; Offringa, A. R.; Riding, J.; Rogers, A. E. E.; Roshi, A.; Shankar, N. Udaya; Srivani, K. S.; Subrahmanyan, R.; Tingay, S. J.; Waterson, M.; Wayth, R. B.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L. (2014-11-21)
      We present the first Murchison Widefield Array observations of the well-known cluster of galaxies Abell 3667 (A3667) between 105 and 241 MHz. A3667 is one of the best known examples of a galaxy cluster hosting a double ...

    • A flare in the jet of Pictor A 

      Marshall, H.L.; Hardcastle, M.J.; Birkinshaw, M.; Croston, J.H.; Evans, D.; Landt, H.; Lenc, E.; Massaro, F.; Perlman, E.; Schwartz, D.A.; Siemiginowska, A.; Stawarz, L.; Urry, C.M.; Worrall, D.M. (2010)
      A Chandra X-ray imaging observation of the jet in Pictor A showed a feature that appears to be a flare that faded between 2000 and 2002. The feature was not detected in a follow-up observation in 2009. The jet itself is ...

    • Galactic synchrotron emissivity measurements between 250° MWA 

      Su, H.; Hurley-Walker, N.; Jackson, C. A.; McClure-Griffiths, N. M.; Tingay, S. J.; Hindson, L.; Hancock, P.; Wayth, R. B.; Gaensler, B. M.; Staveley-Smith, L.; Morgan, J.; Johnston-Hollitt, M.; Lenc, E.; Bell, M. E.; Callingham, J. R.; Dwarkanath, K. S.; For, B. Q.; Kapińska, A. D.; McKinley, B.; Offringa, A. R.; Procopio, P.; Wu, C.; Zheng, Q. (2017-03-01)
      Synchrotron emission pervades the Galactic plane at low radio frequencies, originating from cosmic ray electrons interacting with the Galactic magnetic field. Using a low-frequency radio telescope, the Murchison Widefield ...

    • GLEAM : The GaLactic and Extragalactic All-sky MWA survey 

      Wayth, R. B.; Lenc, E.; Bell, M. E.; Callingham, J. R.; Dwarakanath, K. S.; Franzen, T. M. O.; For, B. -Q.; Gaensler, B.; Hancock, P.; Hindson, L.; Hurley-Walker, N.; Jackson, C. A.; Johnston-Hollitt, M.; Kapinska, A. D.; McKinley, B.; Morgan, J.; Offringa, A. R.; Procopio, P.; Staveley-Smith, L.; Wu, C.; Zheng, Q.; Trott, C. M.; Bernardi, G.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Corey, B. E.; Deshpande, A. A.; Emrich, D.; Goeke, R.; Greenhill, L. J.; Hazelton, B. J.; Kaplan, D. L.; Kasper, J. C.; Kratzenberg, E.; Lonsdale, C. J.; Lynch, M. J.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Ord, S. M.; Prabu, T.; Rogers, A. E. E.; Roshi, A.; Shankar, N. Udaya; Srivani, K. S.; Subrahmanyan, R.; Tingay, S. J.; Waterson, M.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L. (2015-06-22)
      GLEAM, the GaLactic and Extragalactic All-sky MWA survey, is a survey of the entire radio sky south of declination +25 deg at frequencies between 72 and 231 MHz, made with the Murchison Widefield Array (MWA) using a drift ...

    • A high resolution foreground model for the MWA EoR1 field : model and implications for EoR power spectrum analysis 

      Procopio, P.; Wayth, R. B.; Line, J.; Trott, C. M.; Intema, Huib T.; Mitchell, D. A.; Pindor, B.; Riding, J.; Tingay, S. J.; Bell, M. E.; Callingham, J. R.; Dwarakanath, K. S.; For, Bi-Qing; Gaensler, B. M.; Hancock, P. J.; Hindson, L.; Hurley-Walker, N.; Johnston-Hollitt, M.; Kapińnska, A. D.; Lenc, E.; McKinley, B.; Morgan, J.; Offringa, A.; Staveley-Smith, L.; Wu, Chen; Zheng, Q. (2017-08-10)
      The current generation of experiments aiming to detect the neutral hydrogen signal from the Epoch of Reionisation (EoR) is likely to be limited by systematic effects associated with removing foreground sources from target ...

    • High-energy sources at low radio frequency : the Murchison Widefield Array view of Fermi blazars 

      Giroletti, M.; Massaro, F.; D'Abrusco, R.; Lico, R.; Burlon, D.; Hurley-Walker, N.; Johnston-Hollitt, M.; Morgan, J.; Pavlidou, V.; Bell, M.; Bernardi, G.; Bhat, R.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Corey, B. E.; Deshpande, A. A.; Ewall-Rice, A.; Emrich, D.; Gaensler, B. M.; Goeke, R.; Greenhill, L. J.; Hazelton, B. J.; Hindson, L.; Kaplan, D. L.; Kasper, J. C.; Kratzenberg, E.; Feng, L.; Jacobs, D.; Kurdryavtseva, N.; Lenc, E.; Lonsdale, C. J.; Lynch, M. J.; McKinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Offringa, A. R.; Ord, S. M.; Pindor, B.; Prabu, T.; Procopio, P.; Riding, J.; Rogers, A. E. E.; Roshi, A.; Shankar, N. Udaya; Srivani, K. S.; Subrahmanyan, R.; Tingay, S. J.; Waterson, M.; Wayth, R. B.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L. (2016-04-01)
      Low-frequency radio arrays are opening a new window for the study of the sky, both to study new phenomena and to better characterize known source classes. Being flat-spectrum sources, blazars are so far poorly studied at ...

    • The Importance of Wide-field Foreground Removal for 21 cm Cosmology : A Demonstration With Early MWA Epoch of Reionization Observations 

      Pober, J. C.; Hazelton, B. J.; Beardsley, A. P.; Barry, N. A.; Martinot, Z. E.; Sullivan, I. S.; Morales, M. F.; Bell, M. E.; Bernardi, G.; Bhat, N. D. R.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Carroll, P.; Corey, B. E.; Oliveira-Costa, A. de; Deshpande, A. A.; Dillon, Joshua S.; Emrich, D.; Ewall-Wice, A. M.; Feng, L.; Goeke, R.; Greenhill, L. J.; Hewitt, J. N.; Hindson, L.; Hurley-Walker, N.; Jacobs, D. C.; Johnston-Hollitt, M.; Kaplan, D. L.; Kasper, J. C.; Kim, Han-Seek; Kittiwisit, P.; Kratzenberg, E.; Kudryavtseva, N.; Lenc, E.; Line, J.; Loeb, A.; Lonsdale, C. J.; Lynch, M. J.; McKinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morgan, E.; Neben, A. R.; Oberoi, D.; Offringa, A. R.; Ord, S. M.; Paul, Sourabh; Pindor, B.; Prabu, T.; Procopio, P.; Riding, J.; Rogers, A. E. E.; Roshi, A.; Sethi, Shiv K.; Shankar, N. Udaya; Srivani, K. S.; Subrahmanyan, R.; Tegmark, M.; Thyagarajan, Nithyanandan; Tingay, S. J.; Trott, C. M.; Waterson, M.; Wayth, R. B.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L.; Wyithe, J. S. B. (2016-03-01)
      In this paper we present observations, simulations, and analysis demonstrating the direct connection between the location of foreground emission on the sky and its location in cosmological power spectra from interferometric ...

    • Ionospheric modelling using GPS to calibrate the MWA. 1 : Comparison of first order ionospheric effects between GPS models and MWA observations 

      Arora, B. S.; Morgan, J.; Ord, S. M.; Tingay, S. J.; Hurley-Walker, N.; Bell, M.; Bernardi, G.; Bhat, R.; Briggs, F.; Callingham, J. R.; Deshpande, A. A.; Dwarakanath, K. S.; Ewall-Wice, A.; Feng, L.; For, B. -Q.; Hancock, P.; Hazelton, B. J.; Hindson, L.; Jacobs, D.; Johnston-Hollitt, M.; Kapińska, A. D.; Kudryavtseva, N.; Lenc, E.; McKinley, B.; Mitchell, D.; Oberoi, D.; Offringa, A. R.; Pindor, B.; Procopio, P.; Riding, J.; Staveley-Smith, L.; Wayth, R. B.; Wu, C.; Zheng, Q.; Bowman, J. D.; Cappallo, R. J.; Corey, B. E.; Emrich, D.; Goeke, R.; Greenhill, L. J.; Kaplan, D. L.; Kasper, J. C.; Kratzenberg, E.; Lonsdale, C. J.; Lynch, M. J.; McWhirter, S. R.; Morales, M. F.; Morgan, E.; Prabu, T.; Rogers, A. E. E.; Roshi, A.; Shankar, N. Udaya; Srivani, K. S.; Subrahmanyan, R.; Waterson, M.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L. (2015-08-10)
      We compare first order (refractive) ionospheric effects seen by the Murchison Widefield Array (MWA) with the ionosphere as inferred from Global Positioning System (GPS) data. The first order ionosphere manifests itself as ...

    • Ionospheric Modelling using GPS to Calibrate the MWA. II : Regional ionospheric modelling using GPS and GLONASS to estimate ionospheric gradients 

      Arora, B. S.; Morgan, J.; Ord, S. M.; Tingay, S. J.; Bell, M.; Callingham, J. R.; Dwarakanath, K. S.; For, B. -Q.; Hancock, P.; Hindson, L.; Hurley-Walker, N.; Johnston-Hollitt, M.; Kapinska, A. D.; Lenc, E.; McKinley, B.; Offringa, A. R.; Procopio, P.; Staveley-Smith, L.; Wayth, R. B.; Wu, C.; Zheng, Q. (2016-07-13)
      We estimate spatial gradients in the ionosphere using the Global Positioning System (GPS) and GLONASS (Russian global navigation system) observations, utilising data from multiple GPS stations in the vicinity of Murchison ...

    • A Large Scale, Low Frequency Murchison Widefield Array Survey of Galactic HII regions between 260\340 

      Hindson, L.; Johnston-Hollitt, M.; Hurley-Walker, N.; Callingham, J. R.; Su, H.; Morgan, J.; Bell, M.; Bernardi, G.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Deshpande, A. A.; Dwarakanath, K. S.; For, B. -Q; Gaensler, B. M.; Greenhill, L. J.; Hancock, P.; Hazelton, B. J.; Kapinska, A. D.; Kaplan, D. L.; Lenc, E.; Lonsdale, C. J.; Mckinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Offringa, A.; Ord, S. M.; Procopio, P.; Prabu, T.; UdayaShankar, N.; Srivani, K. S.; Staveley-Smith, L.; Subrahmanyan, R.; Tingay, S. J.; Wayth, R. B.; Webster, R. L.; Williams, A.; Williams, C. L.; Wu, C.; Zheng, Q. (2016-05-17)
      We have compiled a catalogue of HII regions detected with the Murchison Widefield Array (MWA) between 72 and 231MHz. The multiple frequency bands provided by the MWA allow us identify the characteristic spectrum generated ...

    • Limits of noise and confusion in the MWA GLEAM year 1 survey 

      Franzen, T. M. O.; Jackson, C. A.; Callingham, J. R.; Ekers, R. D.; Hancock, P. J.; Hurley-Walker, N.; Morgan, J.; Seymour, N.; Wayth, R. B.; White, S. V.; Bell, M. E.; Dwarakanath, K. S.; For, B.; Gaensler, B. M.; Hindson, L.; Johnston-Hollitt, M.; Kapinska, A. D.; Lenc, E.; McKinley, B.; Offringa, A. R.; Procopio, P.; Staveley-Smith, L.; Wu, C.; Zheng, Q. (2015-10-20)
      The GaLactic and Extragalactic All-sky MWA survey (GLEAM) is a new relatively low resolution, contiguous 72-231 MHz survey of the entire sky south of declination +25 deg. In this paper, we outline one approach to determine ...

    • Low Radio Frequency Observations and Spectral Modelling of the Remnant of Supernova 1987A 

      Callingham, J. R.; Gaensler, B. M.; Zanardo, G.; Staveley-Smith, L.; Hancock, P. J.; Hurley-Walker, N.; Bell, M. E.; Dwarakanath, K. S.; Franzen, T. M. O.; Hindson, L.; Johnston-Hollitt, M.; Kapinska, A.; For, B. Q.; Lenc, E.; McKingley, B.; Offringa, A. R.; Procopio, P.; Wayth, R. B.; Wu, C.; Zheng, Q. (2016-10-11)
      We present Murchison Widefield Array observations of the supernova remnant (SNR) 1987A between 72 and 230 MHz, representing the lowest frequency observations of the source to date. This large lever arm in frequency space ...

    • The low-frequency environment of the Murchison Widefield Array : radio-frequency interference analysis and mitigation 

      Offringa, A. R.; Wayth, R. B.; Hurley-Walker, N.; Kaplan, D. L.; Barry, N.; Beardsley, A. P.; Bell, M. E.; Bernardi, G.; Bowman, J. D.; Briggs, F.; Callingham, J. R.; Cappallo, R. J.; Carroll, P.; Deshpande, A. A.; Dillon, J. S.; Dwarakanath, K. S.; Ewall-Wice, A.; Feng, L.; For, B. -Q.; Gaensler, B. M.; Greenhill, L. J.; Hancock, P.; Hazelton, B. J.; Hewitt, J. N.; Hindson, L.; Jacobs, D. C.; Johnston-Hollitt, M.; Kapińska, A. D.; Kim, H. -S.; Kittiwisit, P.; Lenc, E.; Line, J.; Loeb, A.; Lonsdale, C. J.; McKinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Morgan, J.; Neben, A. R.; Oberoi, D.; Ord, S. M.; Paul, S.; Pindor, B.; Pober, J. C.; Prabu, T.; Procopio, P.; Riding, J.; Shankar, N. Udaya; Sethi, S.; Srivani, K. S.; Staveley-Smith, L.; Subrahmanyan, R.; Sullivan, I. S.; Tegmark, M.; Thyagarajan, N.; Tingay, S. J.; Trott, C. M.; Webster, R. L.; Williams, A.; Williams, C. L.; Wu, C.; Wyithe, J. S.; Zheng, Q. (2015-01-16)
      The Murchison Widefield Array (MWA) is a new low-frequency interferometric radio telescope built in Western Australia at one of the locations of the future Square Kilometre Array (SKA). We describe the automated radio-frequency ...