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The MeerKAT telescope as a pulsar facility: System verification and early science results from MeerTime
- M. Bailes, A. Jameson, F. Abbate, E. D. Barr, N. D. R. Bhat, L. Bondonneau, M. Burgay, S. J. Buchner, F. Camilo, D. J. Champion, I. Cognard, P. B. Demorest, P. C. C. Freire, T. Gautam, M. Geyer, J.-M. Griessmeier, L. Guillemot, H. Hu, F. Jankowski, S. Johnston, A. Karastergiou, R. Karuppusamy, D. Kaur, M. J. Keith, M. Kramer, J. van Leeuwen, M. E. Lower, Y. Maan, M. A. McLaughlin, B. W. Meyers, S. Osłowski, L. S. Oswald, A. Parthasarathy, T. Pennucci, B. Posselt, A. Possenti, S. M. Ransom, D. J. Reardon, A. Ridolfi, C. T. G. Schollar, M. Serylak, G. Shaifullah, M. Shamohammadi, R. M. Shannon, C. Sobey, X. Song, R. Spiewak, I. H. Stairs, B. W. Stappers, W. van Straten, A. Szary, G. Theureau, V. Venkatraman Krishnan, P. Weltevrede, N. Wex, T. D. Abbott, G. B. Adams, J. P. Burger, R. R. G. Gamatham, M. Gouws, D. M. Horn, B. Hugo, A. F. Joubert, J. R. Manley, K. McAlpine, S. S. Passmoor, A. Peens-Hough, Z. R Ramudzuli, A. Rust, S. Salie, L. C. Schwardt, R. Siebrits, G. Van Tonder, V. Van Tonder, M. G. Welz
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 37 / 2020
- Published online by Cambridge University Press:
- 15 July 2020, e028
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We describe system verification tests and early science results from the pulsar processor (PTUSE) developed for the newly commissioned 64-dish SARAO MeerKAT radio telescope in South Africa. MeerKAT is a high-gain ( ${\sim}2.8\,\mbox{K Jy}^{-1}$ ) low-system temperature ( ${\sim}18\,\mbox{K at }20\,\mbox{cm}$ ) radio array that currently operates at 580–1 670 MHz and can produce tied-array beams suitable for pulsar observations. This paper presents results from the MeerTime Large Survey Project and commissioning tests with PTUSE. Highlights include observations of the double pulsar $\mbox{J}0737{-}3039\mbox{A}$ , pulse profiles from 34 millisecond pulsars (MSPs) from a single 2.5-h observation of the Globular cluster Terzan 5, the rotation measure of Ter5O, a 420-sigma giant pulse from the Large Magellanic Cloud pulsar PSR $\mbox{J}0540{-}6919$ , and nulling identified in the slow pulsar PSR J0633–2015. One of the key design specifications for MeerKAT was absolute timing errors of less than 5 ns using their novel precise time system. Our timing of two bright MSPs confirm that MeerKAT delivers exceptional timing. PSR $\mbox{J}2241{-}5236$ exhibits a jitter limit of $<4\,\mbox{ns h}^{-1}$ whilst timing of PSR $\mbox{J}1909{-}3744$ over almost 11 months yields an rms residual of 66 ns with only 4 min integrations. Our results confirm that the MeerKAT is an exceptional pulsar telescope. The array can be split into four separate sub-arrays to time over 1 000 pulsars per day and the future deployment of S-band (1 750–3 500 MHz) receivers will further enhance its capabilities.
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- By Núria Duran Adroher, Sergio Aguilar-Gaxiola, Jordi Alonso, Ali Obaid Al-Hamzawi, Laura Helena Andrade, Matthias C. Angermeyer, James Anthony, Corina Benjet, Guilherme Borges, Joshua Breslau, Evelyn J. Bromet, Ronny Bruffaerts, Brendan Bunting, Huibert Burger, José Miguel Caldas de Almeida, Graça Cardoso, Somnath Chatterji, Wai Tat Chiu, Giovanni de Girolamo, Ron de Graaf, Peter de Jonge, Koen Demyttenaere, John Fayyad, Alize J. Ferrari, Silvia Florescu, Anne M. Gadermann, Meyer Glantz, Jen Green, Michael J. Gruber, Oye Gureje, Josep Maria Haro, Yanling He, Steven G. Heeringa, Hristo Hinkov, Chiyi Hu, Yueqin Huang, Irving Hwang, Robert Jin, Elie G. Karam, Norito Kawakami, Ronald C. Kessler, Lola Kola, Viviane Kovess-Masféty, Michael C. Lane, Carmen Lara, William LeBlanc, Sing Lee, Jean-Pierre Lépine, Daphna Levinson, Zhaorui Liu, Gustavo Loera, Herbert Marschinger, Katie A. McLaughlin, Maria Elena Medina-Mora, Elizabeth Miller, Samuel D. Murphy, Aimee Nasser Karam, Matthew K. Nock, Mark A. Oakley Browne, Siobhan O’Neill, Johan Ormel, Beth-Ellen Pennell, Maria V. Petukhova, José Posada-Villa, Rajesh Sagar, Mohammad Salih Khalaf, Nancy A. Sampson, Kathleen Saunders, Michael Schoenbaum, Kate M. Scott, Soraya Seedat, Victoria Shahly, Dan J. Stein, Hisateru Tachimori, Nezar Ismet Taib, Adley Tsang, T. Bedirhan Üstün, Maria Carmen Viana, Gemma Vilagut, Michael R. Von Korff, J. Elisabeth Wells, Harvey A. Whiteford, David R. Williams, Ben Wu, Miguel Xavier, Alan M. Zaslavsky
- Edited by Jordi Alonso, Universitat Pompeu Fabra, Barcelona, Somnath Chatterji, World Health Organization, Geneva, Yanling He
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- The Burdens of Mental Disorders
- Print publication:
- 09 May 2013, pp ix-xii
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Effect of the absence of condensed tannins in faba beans (Vicia faba) on resistance to foot rot, Ascochyta blight and chocolate spot
- J. P. F. G. Helsper, A. Van Norel, K. Burger-Meyer, J. M. Hoogendijk
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- Journal:
- The Journal of Agricultural Science / Volume 123 / Issue 3 / December 1994
- Published online by Cambridge University Press:
- 27 March 2009, pp. 349-355
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The effect of breeding for the absence of condensed tannins in the testa of Vicia faba L. on resistance to foot rot, Ascochyta blight and chocolate spot diseases was investigated in 1988–92 at Wageningen, The Netherlands. For this purpose the disease development in tannin-free and tannin-containing partners of six near-isogenic pairs was compared after exposure to causative pathogens. Except for one near-isogenic pair, in which both partner lines showed a relatively high resistance, the tannin-free lines were more susceptible to foot rot than the tannin-containing partners of the same pair. This observation indicates that the presence of condensed tannins in the testa prevents infection of the plant by the causative pathogens. Fusarium oxysporum and F. solani, isolated from faba bean tissues showing foot rot symptoms, were shown to be primary foot rot pathogens, while F. avenaceum caused wilting of young plantlets. No pathogenic isolates were obtained from F. tabacinum. Resistance to Botrytis fabae (chocolate spot disease), scored on leaves and stems under glasshouse and field conditions in 1992, was not influenced by selection for the absence of condensed tannins which occur in the testa of mature seeds. Under the same environmental conditions, leaves, stems, pods and seeds of tannin-free lines showed similar levels of damage due to Ascochyta fabae (Ascochyta blight) as the tannin-containing partner lines of the same near-isogenic pair. These results indicate that condensed tannins do not play a role in resistance to both B. fabae and A. fabae, probably because, except for the seeds, these polyphenols do not accumulate in the tissues affected by these pathogens.