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1. The SARAO MeerKAT 1.3 GHz Galactic Plane Survey

Author: Goedhart, S., Cotton, W. D., Camilo, F., Thompson, M. A., Umana, G., Bietenholz, M., Woudt, P. A., Anderson, L. D., Bordiu, C., Buckley, D. A. H., Buemi, C. S., Bufano, F., Cavallaro, F., Chen, H., Chibueze, J. O., Egbo, D., Frank, B. S., Hoare, M. G., Ingallinera, A., Irabor, T., Kraan-Korteweg, R. C., Kurapati, S., Leto, P., Loru, S., Mutale, M., Obonyo, W. O., Plavin, A., Rajohnson, S. H. A., Rigby, A., Riggi, S., Seidu, M., Serra, P., Smart, B. M., Stappers, B. W., Steyn, N., Surnis, M., Trigilio, C., Williams, G. M., Abbott, T. D., Adam, R. M., Asad, K. M. B., Baloyi, T., Bauermeister, E. F., Bennet, T. G. H., Bester, H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., Cloete, K., de Villiers, M. S., de Villiers, D. I. L., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., Fourie, D. J., Gamatham, R. R. G., Gatsi, T. G., Geyer, M., Gouws, M., Gumede, S. C., Heywood, I., Hokwana, A., Hoosen, S. W., Horn, D. M., Horrell, L. M. G., Hugo, B. V., Isaacson, A. I., Józsa, G. I. G., Jonas, J. L., Jordaan, J. D. B. L., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kriek, N., Kriel, H., Krishnan, V. K., Kusel, T. W., Legodi, L. S., Lehmensiek, R., Lord, R. T., Macfarlane, P. S., Magnus, L. G., Magozore, C., Main, J. P. L., Malan, J. A., Manley, J. R., Marais, S. J., Maree, M. D. J., Martens, A., Maruping, P., McAlpine, K., Merry, B. C., Mgodeli, M., Millenaar, R. P., Mokone, O. J., Monama, T. E., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Nicolson, G. D., Ockards, M. T., Oozeer, N., Passmoor, S. S., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ratcliffe, S. M., Renil, R., Richter, L. L., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M. J., Smirnov, O. M., Tiplady, A. J., van Balla, T. J., van der Byl, A., Van Tonder, V., Venter, A. J., Venter, M., Welz, M. G., Williams, L. P., Goedhart, S., Cotton, W. D., Camilo, F., Thompson, M. A., Umana, G., Bietenholz, M., Woudt, P. A., Anderson, L. D., Bordiu, C., Buckley, D. A. H., Buemi, C. S., Bufano, F., Cavallaro, F., Chen, H., Chibueze, J. O., Egbo, D., Frank, B. S., Hoare, M. G., Ingallinera, A., Irabor, T., Kraan-Korteweg, R. C., Kurapati, S., Leto, P., Loru, S., Mutale, M., Obonyo, W. O., Plavin, A., Rajohnson, S. H. A., Rigby, A., Riggi, S., Seidu, M., Serra, P., Smart, B. M., Stappers, B. W., Steyn, N., Surnis, M., Trigilio, C., Williams, G. M., Abbott, T. D., Adam, R. M., Asad, K. M. B., Baloyi, T., Bauermeister, E. F., Bennet, T. G. H., Bester, H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., Cloete, K., de Villiers, M. S., de Villiers, D. I. L., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., Fourie, D. J., Gamatham, R. R. G., Gatsi, T. G., Geyer, M., Gouws, M., Gumede, S. C., Heywood, I., Hokwana, A., Hoosen, S. W., Horn, D. M., Horrell, L. M. G., Hugo, B. V., Isaacson, A. I., Józsa, G. I. G., Jonas, J. L., Jordaan, J. D. B. L., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kriek, N., Kriel, H., Krishnan, V. K., Kusel, T. W., Legodi, L. S., Lehmensiek, R., Lord, R. T., Macfarlane, P. S., Magnus, L. G., Magozore, C., Main, J. P. L., Malan, J. A., Manley, J. R., Marais, S. J., Maree, M. D. J., Martens, A., Maruping, P., McAlpine, K., Merry, B. C., Mgodeli, M., Millenaar, R. P., Mokone, O. J., Monama, T. E., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Nicolson, G. D., Ockards, M. T., Oozeer, N., Passmoor, S. S., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ratcliffe, S. M., Renil, R., Richter, L. L., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M. J., Smirnov, O. M., Tiplady, A. J., van Balla, T. J., van der Byl, A., Van Tonder, V., Venter, A. J., Venter, M., Welz, M. G., and Williams, L. P.
Abstract: We present the SARAO MeerKAT Galactic Plane Survey (SMGPS), a 1.3 GHz continuum survey of almost half of the Galactic Plane (251\deg $\le l \le$ 358\deg and 2\deg $\le l \le$ 61\deg at $|b| \le 1.5\deg $). SMGPS is the largest, most sensitive and highest angular resolution 1 GHz survey of the Plane yet carried out, with an angular resolution of 8" and a broadband RMS sensitivity of $\sim$10--20 $\mu$ Jy/beam. Here we describe the first publicly available data release from SMGPS which comprises data cubes of frequency-resolved images over 908--1656 MHz, power law fits to the images, and broadband zeroth moment integrated intensity images. A thorough assessment of the data quality and guidance for future usage of the data products are given. Finally, we discuss the tremendous potential of SMGPS by showcasing highlights of the Galactic and extragalactic science that it permits. These highlights include the discovery of a new population of non-thermal radio filaments; identification of new candidate supernova remnants, pulsar wind nebulae and planetary nebulae; improved radio/mid-IR classification of rare Luminous Blue Variables and discovery of associated extended radio nebulae; new radio stars identified by Bayesian cross-matching techniques; the realisation that many of the largest radio-quiet WISE HII region candidates are not true HII regions; and a large sample of previously undiscovered background HI galaxies in the Zone of Avoidance., Comment: Submitted to MNRAS. Comments are welcome. The data release will be publicly available on acceptance of the paper
Published: 2023

2. The 1.28 GHz MeerKAT Galactic Center Mosaic

Author: Heywood, I., Rammala, I., Camilo, F., Cotton, W. D., Yusef-Zadeh, F., Abbott, T. D., Adam, R. M., Adams, G., Aldera, M. A., Asad, K. M. B., Bauermeister, E. F., Bennett, T. G. H., Bester, H. L., Bode, W. A., Botha, D. H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., de Villiers, D. I. L., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., February, S., Fourie, D. J., Frank, B. S., Gamatham, R. R. G., Geyer, M., Goedhart, S., Gouws, M., Gumede, S. C., Hlakola, M. J., Hokwana, A., Hoosen, S. W., Horrell, J. M. G., Hugo, B., Isaacson, A. I., Józsa, G. I. G., Jonas, J. L., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kenyon, J. S., Kotzé, P. P. A., Kriek, N., Kriel, H., Krishnan, V. K., Lehmensiek, R., Liebenberg, D., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Mahgoub, O., Makhaba, A., Makhathini, S., Malan, J. A., Manley, J. R., Marais, S. J., Martens, A., Mauch, T., Merry, B. C., Millenaar, R. P., Mnyandu, N., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T., Oozeer, N., Otto, A. J., Passmoor, S. S., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ramanujam, N. M. R., Ramudzuli, Z. R., Ratcliffe, S. M., Robyntjies, A., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M., Smirnov, O. M., Sofeya, L., Taljaard, B., Tasse, C., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., Van Tonder, V., Van Wyk, R., Venter, A. J., Venter, M., Wallace, B. H., Welz, M. G., Williams, L. P., Xaia, B., Heywood, I., Rammala, I., Camilo, F., Cotton, W. D., Yusef-Zadeh, F., Abbott, T. D., Adam, R. M., Adams, G., Aldera, M. A., Asad, K. M. B., Bauermeister, E. F., Bennett, T. G. H., Bester, H. L., Bode, W. A., Botha, D. H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., de Villiers, D. I. L., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., February, S., Fourie, D. J., Frank, B. S., Gamatham, R. R. G., Geyer, M., Goedhart, S., Gouws, M., Gumede, S. C., Hlakola, M. J., Hokwana, A., Hoosen, S. W., Horrell, J. M. G., Hugo, B., Isaacson, A. I., Józsa, G. I. G., Jonas, J. L., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kenyon, J. S., Kotzé, P. P. A., Kriek, N., Kriel, H., Krishnan, V. K., Lehmensiek, R., Liebenberg, D., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Mahgoub, O., Makhaba, A., Makhathini, S., Malan, J. A., Manley, J. R., Marais, S. J., Martens, A., Mauch, T., Merry, B. C., Millenaar, R. P., Mnyandu, N., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T., Oozeer, N., Otto, A. J., Passmoor, S. S., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ramanujam, N. M. R., Ramudzuli, Z. R., Ratcliffe, S. M., Robyntjies, A., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M., Smirnov, O. M., Sofeya, L., Taljaard, B., Tasse, C., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., Van Tonder, V., Van Wyk, R., Venter, A. J., Venter, M., Wallace, B. H., Welz, M. G., Williams, L. P., and Xaia, B.
Abstract: The inner $\sim$200 pc region of the Galaxy contains a 4 million M$_{\odot}$ supermassive black hole (SMBH), significant quantities of molecular gas, and star formation and cosmic ray energy densities that are roughly two orders of magnitude higher than the corresponding levels in the Galactic disk. At a distance of only 8.2 kpc, the region presents astronomers with a unique opportunity to study a diverse range of energetic astrophysical phenomena, from stellar objects in extreme environments, to the SMBH and star-formation driven feedback processes that are known to influence the evolution of galaxies as a whole. We present a new survey of the Galactic center conducted with the South African MeerKAT radio telescope. Radio imaging offers a view that is unaffected by the large quantities of dust that obscure the region at other wavelengths, and a scene of striking complexity is revealed. We produce total intensity and spectral index mosaics of the region from 20 pointings (144 hours on-target in total), covering 6.5 square degrees with an angular resolution of 4$"$,at a central frequency of 1.28 GHz. Many new features are revealed for the first time due to a combination of MeerKAT's high sensitivity, exceptional $u,v$-plane coverage, and geographical vantage point. We highlight some initial survey results, including new supernova remnant candidates, many new non-thermal filament complexes, and enhanced views of the Radio Arc Bubble, Sgr A and Sgr B regions. This project is a SARAO public legacy survey, and the image products are made available with this article., Comment: 29 pages, 15 figures, 3 tables, accepted for publication in the The Astrophysical Journal. Replacement arXiv version with higher quality figures
Published: 2022
Full Text: View/download PDF

3. The 1.28 GHz MeerKAT Galactic Center Mosaic

Author: Heywood, I., Rammala, I., Camilo, F., Cotton, W. D., Yusef-Zadeh, F., Abbott, T. D., Adam, R. M., Adams, G., Aldera, M. A., Asad, K. M. B., Bauermeister, E. F., Bennett, T. G. H., Bester, H. L., Bode, W. A., Botha, D. H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., de Villiers, D. I. L., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., February, S., Fourie, D. J., Frank, B. S., Gamatham, R. R. G., Geyer, M., Goedhart, S., Gouws, M., Gumede, S. C., Hlakola, M. J., Hokwana, A., Hoosen, S. W., Horrell, J. M. G., Hugo, B., Isaacson, A. I., Józsa, G. I. G., Jonas, J. L., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kenyon, J. S., Kotzé, P. P. A., Kriek, N., Kriel, H., Krishnan, V. K., Lehmensiek, R., Liebenberg, D., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Mahgoub, O., Makhaba, A., Makhathini, S., Malan, J. A., Manley, J. R., Marais, S. J., Martens, A., Mauch, T., Merry, B. C., Millenaar, R. P., Mnyandu, N., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T., Oozeer, N., Otto, A. J., Passmoor, S. S., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ramanujam, N. M. R., Ramudzuli, Z. R., Ratcliffe, S. M., Robyntjies, A., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M., Smirnov, O. M., Sofeya, L., Taljaard, B., Tasse, C., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., Van Tonder, V., Van Wyk, R., Venter, A. J., Venter, M., Wallace, B. H., Welz, M. G., Williams, L. P., Xaia, B., Heywood, I., Rammala, I., Camilo, F., Cotton, W. D., Yusef-Zadeh, F., Abbott, T. D., Adam, R. M., Adams, G., Aldera, M. A., Asad, K. M. B., Bauermeister, E. F., Bennett, T. G. H., Bester, H. L., Bode, W. A., Botha, D. H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., de Villiers, D. I. L., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., February, S., Fourie, D. J., Frank, B. S., Gamatham, R. R. G., Geyer, M., Goedhart, S., Gouws, M., Gumede, S. C., Hlakola, M. J., Hokwana, A., Hoosen, S. W., Horrell, J. M. G., Hugo, B., Isaacson, A. I., Józsa, G. I. G., Jonas, J. L., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kenyon, J. S., Kotzé, P. P. A., Kriek, N., Kriel, H., Krishnan, V. K., Lehmensiek, R., Liebenberg, D., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Mahgoub, O., Makhaba, A., Makhathini, S., Malan, J. A., Manley, J. R., Marais, S. J., Martens, A., Mauch, T., Merry, B. C., Millenaar, R. P., Mnyandu, N., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T., Oozeer, N., Otto, A. J., Passmoor, S. S., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ramanujam, N. M. R., Ramudzuli, Z. R., Ratcliffe, S. M., Robyntjies, A., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M., Smirnov, O. M., Sofeya, L., Taljaard, B., Tasse, C., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., Van Tonder, V., Van Wyk, R., Venter, A. J., Venter, M., Wallace, B. H., Welz, M. G., Williams, L. P., and Xaia, B.
Abstract: The inner $\sim$200 pc region of the Galaxy contains a 4 million M$_{\odot}$ supermassive black hole (SMBH), significant quantities of molecular gas, and star formation and cosmic ray energy densities that are roughly two orders of magnitude higher than the corresponding levels in the Galactic disk. At a distance of only 8.2 kpc, the region presents astronomers with a unique opportunity to study a diverse range of energetic astrophysical phenomena, from stellar objects in extreme environments, to the SMBH and star-formation driven feedback processes that are known to influence the evolution of galaxies as a whole. We present a new survey of the Galactic center conducted with the South African MeerKAT radio telescope. Radio imaging offers a view that is unaffected by the large quantities of dust that obscure the region at other wavelengths, and a scene of striking complexity is revealed. We produce total intensity and spectral index mosaics of the region from 20 pointings (144 hours on-target in total), covering 6.5 square degrees with an angular resolution of 4$"$,at a central frequency of 1.28 GHz. Many new features are revealed for the first time due to a combination of MeerKAT's high sensitivity, exceptional $u,v$-plane coverage, and geographical vantage point. We highlight some initial survey results, including new supernova remnant candidates, many new non-thermal filament complexes, and enhanced views of the Radio Arc Bubble, Sgr A and Sgr B regions. This project is a SARAO public legacy survey, and the image products are made available with this article., Comment: 29 pages, 15 figures, 3 tables, accepted for publication in the The Astrophysical Journal. Replacement arXiv version with higher quality figures
Published: 2022
Full Text: View/download PDF

4. The MeerKAT Telescope as a Pulsar Facility: System verification and early science results from MeerTime

Author: Bailes, M, Jameson, A, Abbate, F, Barr, E, Bhat, N, Bondonneau, L, Burgay, M, Buchner, S, Camilo, F, Champion, D, Cognard, I, Demorest, P, Freire, P, Gautam, T, Geyer, M, Griessmeier, J, Guillemot, L, Hu, H, Jankowski, F, Johnston, S, Karastergiou, A, Karuppusamy, R, Kaur, D, Keith, M, Kramer, M, van Leeuwen, J, Lower, M, Maan, Y, Mclaughlin, M, Meyers, B, Osłowski, S, Oswald, L, Parthasarathy, A, Pennucci, T, Posselt, B, Possenti, A, Ransom, S, Reardon, D, Ridolfi, A, Schollar, C, Serylak, M, Shaifullah, G, Shamohammadi, M, Shannon, R, Sobey, C, Song, X, Spiewak, R, Stairs, I, Stappers, B, van Straten, W, Szary, A, Theureau, G, Venkatraman Krishnan, V, Weltevrede, P, Wex, N, Abbott, T, Adams, G, Burger, J, Gamatham, R, Gouws, M, Horn, D, Hugo, B, Joubert, A, Manley, J, Mcalpine, K, Passmoor, S, Peens-Hough, A, Ramudzuli, Z, Rust, A, Salie, S, Schwardt, L, Siebrits, R, Van Tonder, G, Van Tonder, V, Welz, M, Bailes, M., Jameson, A., Abbate, F., Barr, E. D., Bhat, N. D. R., Bondonneau, L., Burgay, M., Buchner, S. J., Camilo, F., Champion, D. J., Cognard, I., Demorest, P. B., Freire, P. C. C., Gautam, T., Geyer, M., Griessmeier, J. M., Guillemot, L., Hu, H., Jankowski, F., Johnston, S., Karastergiou, A., Karuppusamy, R., Kaur, D., Keith, M. J., Kramer, M., van Leeuwen, J., Lower, M. E., Maan, Y., McLaughlin, M. A., Meyers, B. W., Osłowski, S., Oswald, L. S., Parthasarathy, A., Pennucci, T., Posselt, B., Possenti, A., Ransom, S. M., Reardon, D. J., Ridolfi, A., Schollar, C. T. G., Serylak, M., Shaifullah, G., Shamohammadi, M., Shannon, R. M., Sobey, C., Song, X., Spiewak, R., Stairs, I. H., Stappers, B. W., van Straten, W., Szary, A., Theureau, G., Venkatraman Krishnan, V., Weltevrede, P., Wex, N., Abbott, T. D., Adams, G. B., Burger, J. P., Gamatham, R. R. G., Gouws, M., Horn, D. M., Hugo, B., Joubert, A. F., Manley, J. R., McAlpine, K., Passmoor, S. S., Peens-Hough, A., Ramudzuli, Z. R., Rust, A., Salie, S., Schwardt, L. C., Siebrits, R., Van Tonder, G., Van Tonder, V., Welz, M. G., Bailes, M, Jameson, A, Abbate, F, Barr, E, Bhat, N, Bondonneau, L, Burgay, M, Buchner, S, Camilo, F, Champion, D, Cognard, I, Demorest, P, Freire, P, Gautam, T, Geyer, M, Griessmeier, J, Guillemot, L, Hu, H, Jankowski, F, Johnston, S, Karastergiou, A, Karuppusamy, R, Kaur, D, Keith, M, Kramer, M, van Leeuwen, J, Lower, M, Maan, Y, Mclaughlin, M, Meyers, B, Osłowski, S, Oswald, L, Parthasarathy, A, Pennucci, T, Posselt, B, Possenti, A, Ransom, S, Reardon, D, Ridolfi, A, Schollar, C, Serylak, M, Shaifullah, G, Shamohammadi, M, Shannon, R, Sobey, C, Song, X, Spiewak, R, Stairs, I, Stappers, B, van Straten, W, Szary, A, Theureau, G, Venkatraman Krishnan, V, Weltevrede, P, Wex, N, Abbott, T, Adams, G, Burger, J, Gamatham, R, Gouws, M, Horn, D, Hugo, B, Joubert, A, Manley, J, Mcalpine, K, Passmoor, S, Peens-Hough, A, Ramudzuli, Z, Rust, A, Salie, S, Schwardt, L, Siebrits, R, Van Tonder, G, Van Tonder, V, Welz, M, Bailes, M., Jameson, A., Abbate, F., Barr, E. D., Bhat, N. D. R., Bondonneau, L., Burgay, M., Buchner, S. J., Camilo, F., Champion, D. J., Cognard, I., Demorest, P. B., Freire, P. C. C., Gautam, T., Geyer, M., Griessmeier, J. M., Guillemot, L., Hu, H., Jankowski, F., Johnston, S., Karastergiou, A., Karuppusamy, R., Kaur, D., Keith, M. J., Kramer, M., van Leeuwen, J., Lower, M. E., Maan, Y., McLaughlin, M. A., Meyers, B. W., Osłowski, S., Oswald, L. S., Parthasarathy, A., Pennucci, T., Posselt, B., Possenti, A., Ransom, S. M., Reardon, D. J., Ridolfi, A., Schollar, C. T. G., Serylak, M., Shaifullah, G., Shamohammadi, M., Shannon, R. M., Sobey, C., Song, X., Spiewak, R., Stairs, I. H., Stappers, B. W., van Straten, W., Szary, A., Theureau, G., Venkatraman Krishnan, V., Weltevrede, P., Wex, N., Abbott, T. D., Adams, G. B., Burger, J. P., Gamatham, R. R. G., Gouws, M., Horn, D. M., Hugo, B., Joubert, A. F., Manley, J. R., McAlpine, K., Passmoor, S. S., Peens-Hough, A., Ramudzuli, Z. R., Rust, A., Salie, S., Schwardt, L. C., Siebrits, R., Van Tonder, G., Van Tonder, V., and Welz, M. G.
Abstract: 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 low-system temperature 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, 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 , 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 exhibits a jitter limit of whilst timing of PSR 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.
Published: 2020

5. The MeerKAT Galaxy Cluster Legacy Survey I. Survey Overview and Highlights

Author: Knowles, K., Cotton, W. D., Rudnick, L., Camilo, F., Goedhart, S., Deane, R., Ramatsoku, M., Bietenholz, M. F., Brüggen, M., Button, C., Chen, H., Chibueze, J. O., Clarke, T. E., de Gasperin, F., Ianjamasimanana, R., Józsa, G. I. G., Hilton, M., Kesebonye, K. C., Kolokythas, K., Kraan-Korteweg, R. C., Lawrie, G., Lochner, M., Loubser, S. I., Marchegiani, P., Mhlahlo, N., Moodley, K., Murphy, E., Namumba, B., Oozeer, N., Parekh, V., Pillay, D. S., Passmoor, S. S., Ramaila, A. J. T., Ranchod, S., Retana-Montenegro, E., Sebokolodi, L., Sikhosana, S. P., Smirnov, O., Thorat, K., Venturi, T., Abbott, T. D., Adam, R. M., Adams, G., Aldera, M. A., Bauermeister, E. F., Bennett, T. G. H., Bode, W. A., Botha, D. H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., de Villiers, D. I. L., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fadana, G., Fanaroff, B. L., Fataar, S., Foley, A. R., Fourie, D. J., Frank, B. S., Gamatham, R. R. G., Gatsi, T. G., Geyer, M., Gouws, M., Gumede, S. C., Heywood, I., Hlakola, M. J., Hokwana, A., Hoosen, S. W., Horn, D. M., Horrell, J. M. G., Hugo, B. V., Isaacson, A. R., Jonas, J. L., Jordaan, J. D. B., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kasper, V. A., Kenyon, J. S., Kotzé, P. P. A., Kotze, A. G., Kriek, N., Kriel, H., Krishnan, V. K., Kusel, T. W., Legodi, L. S., Lehmensiek, R., Liebenberg, D., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Main, J. P. L., Makhaba, A., Makhathini, S., Malan, J. A., Manley, J. R., Marais, S. J., Maree, M. D. J., Martens, A., Mauch, T., McAlpine, K., Merry, B. C., Millenaar, R. P., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T., Otto, A. J., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramanujam, N. M., Ramudzuli, Z. R., Ratcliffe, S. M., Renil, R., Robyntjies, A., Rust, A. N., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M., Sofeya, L., Taljaard, B., Tasse, C., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., van Dyk, C. L., Van Tonder, V., Van Wyk, R., Venter, A. J., Venter, M., Welz, M. G., Williams, L. P., Xaia, B., Knowles, K., Cotton, W. D., Rudnick, L., Camilo, F., Goedhart, S., Deane, R., Ramatsoku, M., Bietenholz, M. F., Brüggen, M., Button, C., Chen, H., Chibueze, J. O., Clarke, T. E., de Gasperin, F., Ianjamasimanana, R., Józsa, G. I. G., Hilton, M., Kesebonye, K. C., Kolokythas, K., Kraan-Korteweg, R. C., Lawrie, G., Lochner, M., Loubser, S. I., Marchegiani, P., Mhlahlo, N., Moodley, K., Murphy, E., Namumba, B., Oozeer, N., Parekh, V., Pillay, D. S., Passmoor, S. S., Ramaila, A. J. T., Ranchod, S., Retana-Montenegro, E., Sebokolodi, L., Sikhosana, S. P., Smirnov, O., Thorat, K., Venturi, T., Abbott, T. D., Adam, R. M., Adams, G., Aldera, M. A., Bauermeister, E. F., Bennett, T. G. H., Bode, W. A., Botha, D. H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., de Villiers, D. I. L., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fadana, G., Fanaroff, B. L., Fataar, S., Foley, A. R., Fourie, D. J., Frank, B. S., Gamatham, R. R. G., Gatsi, T. G., Geyer, M., Gouws, M., Gumede, S. C., Heywood, I., Hlakola, M. J., Hokwana, A., Hoosen, S. W., Horn, D. M., Horrell, J. M. G., Hugo, B. V., Isaacson, A. R., Jonas, J. L., Jordaan, J. D. B., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kasper, V. A., Kenyon, J. S., Kotzé, P. P. A., Kotze, A. G., Kriek, N., Kriel, H., Krishnan, V. K., Kusel, T. W., Legodi, L. S., Lehmensiek, R., Liebenberg, D., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Main, J. P. L., Makhaba, A., Makhathini, S., Malan, J. A., Manley, J. R., Marais, S. J., Maree, M. D. J., Martens, A., Mauch, T., McAlpine, K., Merry, B. C., Millenaar, R. P., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T., Otto, A. J., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramanujam, N. M., Ramudzuli, Z. R., Ratcliffe, S. M., Renil, R., Robyntjies, A., Rust, A. N., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M., Sofeya, L., Taljaard, B., Tasse, C., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., van Dyk, C. L., Van Tonder, V., Van Wyk, R., Venter, A. J., Venter, M., Welz, M. G., Williams, L. P., and Xaia, B.
Abstract: MeerKAT's large number of antennas, spanning 8 km with a densely packed 1 km core, create a powerful instrument for wide-area surveys, with high sensitivity over a wide range of angular scales. The MeerKAT Galaxy Cluster Legacy Survey (MGCLS) is a programme of long-track MeerKAT L-band (900-1670 MHz) observations of 115 galaxy clusters, observed for $\sim$6-10 hours each in full polarisation. The first legacy product data release (DR1), made available with this paper, includes the MeerKAT visibilities, basic image cubes at $\sim$8" resolution, and enhanced spectral and polarisation image cubes at $\sim$8" and 15" resolutions. Typical sensitivities for the full-resolution MGCLS image products are $\sim$3-5 {\mu}Jy/beam. The basic cubes are full-field and span 4 deg^2. The enhanced products consist of the inner 1.44 deg^2 field of view, corrected for the primary beam. The survey is fully sensitive to structures up to $\sim$10' scales and the wide bandwidth allows spectral and Faraday rotation mapping. HI mapping at 209 kHz resolution can be done at $0
Published: 2021
Full Text: View/download PDF

6. The MeerKAT Galaxy Cluster Legacy Survey I. Survey Overview and Highlights

Author: Knowles, K., Cotton, W. D., Rudnick, L., Camilo, F., Goedhart, S., Deane, R., Ramatsoku, M., Bietenholz, M. F., Brüggen, M., Button, C., Chen, H., Chibueze, J. O., Clarke, T. E., de Gasperin, F., Ianjamasimanana, R., Józsa, G. I. G., Hilton, M., Kesebonye, K. C., Kolokythas, K., Kraan-Korteweg, R. C., Lawrie, G., Lochner, M., Loubser, S. I., Marchegiani, P., Mhlahlo, N., Moodley, K., Murphy, E., Namumba, B., Oozeer, N., Parekh, V., Pillay, D. S., Passmoor, S. S., Ramaila, A. J. T., Ranchod, S., Retana-Montenegro, E., Sebokolodi, L., Sikhosana, S. P., Smirnov, O., Thorat, K., Venturi, T., Abbott, T. D., Adam, R. M., Adams, G., Aldera, M. A., Bauermeister, E. F., Bennett, T. G. H., Bode, W. A., Botha, D. H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., de Villiers, D. I. L., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fadana, G., Fanaroff, B. L., Fataar, S., Foley, A. R., Fourie, D. J., Frank, B. S., Gamatham, R. R. G., Gatsi, T. G., Geyer, M., Gouws, M., Gumede, S. C., Heywood, I., Hlakola, M. J., Hokwana, A., Hoosen, S. W., Horn, D. M., Horrell, J. M. G., Hugo, B. V., Isaacson, A. R., Jonas, J. L., Jordaan, J. D. B., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kasper, V. A., Kenyon, J. S., Kotzé, P. P. A., Kotze, A. G., Kriek, N., Kriel, H., Krishnan, V. K., Kusel, T. W., Legodi, L. S., Lehmensiek, R., Liebenberg, D., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Main, J. P. L., Makhaba, A., Makhathini, S., Malan, J. A., Manley, J. R., Marais, S. J., Maree, M. D. J., Martens, A., Mauch, T., McAlpine, K., Merry, B. C., Millenaar, R. P., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T., Otto, A. J., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramanujam, N. M., Ramudzuli, Z. R., Ratcliffe, S. M., Renil, R., Robyntjies, A., Rust, A. N., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M., Sofeya, L., Taljaard, B., Tasse, C., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., van Dyk, C. L., Van Tonder, V., Van Wyk, R., Venter, A. J., Venter, M., Welz, M. G., Williams, L. P., Xaia, B., Knowles, K., Cotton, W. D., Rudnick, L., Camilo, F., Goedhart, S., Deane, R., Ramatsoku, M., Bietenholz, M. F., Brüggen, M., Button, C., Chen, H., Chibueze, J. O., Clarke, T. E., de Gasperin, F., Ianjamasimanana, R., Józsa, G. I. G., Hilton, M., Kesebonye, K. C., Kolokythas, K., Kraan-Korteweg, R. C., Lawrie, G., Lochner, M., Loubser, S. I., Marchegiani, P., Mhlahlo, N., Moodley, K., Murphy, E., Namumba, B., Oozeer, N., Parekh, V., Pillay, D. S., Passmoor, S. S., Ramaila, A. J. T., Ranchod, S., Retana-Montenegro, E., Sebokolodi, L., Sikhosana, S. P., Smirnov, O., Thorat, K., Venturi, T., Abbott, T. D., Adam, R. M., Adams, G., Aldera, M. A., Bauermeister, E. F., Bennett, T. G. H., Bode, W. A., Botha, D. H., Botha, A. G., Brederode, L. R. S., Buchner, S., Burger, J. P., Cheetham, T., de Villiers, D. I. L., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fadana, G., Fanaroff, B. L., Fataar, S., Foley, A. R., Fourie, D. J., Frank, B. S., Gamatham, R. R. G., Gatsi, T. G., Geyer, M., Gouws, M., Gumede, S. C., Heywood, I., Hlakola, M. J., Hokwana, A., Hoosen, S. W., Horn, D. M., Horrell, J. M. G., Hugo, B. V., Isaacson, A. R., Jonas, J. L., Jordaan, J. D. B., Joubert, A. F., Julie, R. P. M., Kapp, F. B., Kasper, V. A., Kenyon, J. S., Kotzé, P. P. A., Kotze, A. G., Kriek, N., Kriel, H., Krishnan, V. K., Kusel, T. W., Legodi, L. S., Lehmensiek, R., Liebenberg, D., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Main, J. P. L., Makhaba, A., Makhathini, S., Malan, J. A., Manley, J. R., Marais, S. J., Maree, M. D. J., Martens, A., Mauch, T., McAlpine, K., Merry, B. C., Millenaar, R. P., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T., Otto, A. J., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramanujam, N. M., Ramudzuli, Z. R., Ratcliffe, S. M., Renil, R., Robyntjies, A., Rust, A. N., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L. C., Schwartz, R. L., Serylak, M., Siebrits, R., Sirothia, S. K., Slabber, M., Sofeya, L., Taljaard, B., Tasse, C., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., van Dyk, C. L., Van Tonder, V., Van Wyk, R., Venter, A. J., Venter, M., Welz, M. G., Williams, L. P., and Xaia, B.
Abstract: MeerKAT's large number of antennas, spanning 8 km with a densely packed 1 km core, create a powerful instrument for wide-area surveys, with high sensitivity over a wide range of angular scales. The MeerKAT Galaxy Cluster Legacy Survey (MGCLS) is a programme of long-track MeerKAT L-band (900-1670 MHz) observations of 115 galaxy clusters, observed for $\sim$6-10 hours each in full polarisation. The first legacy product data release (DR1), made available with this paper, includes the MeerKAT visibilities, basic image cubes at $\sim$8" resolution, and enhanced spectral and polarisation image cubes at $\sim$8" and 15" resolutions. Typical sensitivities for the full-resolution MGCLS image products are $\sim$3-5 {\mu}Jy/beam. The basic cubes are full-field and span 4 deg^2. The enhanced products consist of the inner 1.44 deg^2 field of view, corrected for the primary beam. The survey is fully sensitive to structures up to $\sim$10' scales and the wide bandwidth allows spectral and Faraday rotation mapping. HI mapping at 209 kHz resolution can be done at $0
Published: 2021
Full Text: View/download PDF

7. The MeerKAT Telescope as a Pulsar Facility: System verification and early science results from MeerTime

Author: Bailes, M., Jameson, A., Abbate, F., Barr, E. D., Bhat, N. D. R., Bondonneau, L., Burgay, M., Buchner, S. J., Camilo, F., Champion, D. J., Cognard, I., Demorest, P. B., Freire, P. C. C., Gautam, T., Geyer, M., Griessmeier, J. M., Guillemot, L., Hu, H., Jankowski, F., Johnston, S., Karastergiou, A., Karuppusamy, R., Kaur, D., Keith, M. J., Kramer, M., van Leeuwen, J., Lower, M. E., Maan, Y., McLaughlin, M. A., Meyers, B. W., Osłowski, S., Oswald, L. S., Parthasarathy, A., Pennucci, T., Posselt, B., Possenti, A., Ransom, S. M., Reardon, D. J., Ridolfi, A., Schollar, C. T. G., Serylak, M., Shaifullah, G., Shamohammadi, M., Shannon, R. M., Sobey, C., Song, X., Spiewak, R., Stairs, I. H., Stappers, B. W., van Straten, W., Szary, A., Theureau, G., Krishnan, V. Venkatraman, Weltevrede, P., Wex, N., Abbott, T. D., Adams, G. B., Burger, J. P., Gamatham, R. R. G., Gouws, M., Horn, D. M., Hugo, B., Joubert, A. F., Manley, J. R., McAlpine, K., Passmoor, S. S., Peens-Hough, A., Ramudzuli, Z. R., Rust, A., Salie, S., Schwardt, L. C., Siebrits, R., Van Tonder, G., Van Tonder, V., Welz, M. G., Bailes, M., Jameson, A., Abbate, F., Barr, E. D., Bhat, N. D. R., Bondonneau, L., Burgay, M., Buchner, S. J., Camilo, F., Champion, D. J., Cognard, I., Demorest, P. B., Freire, P. C. C., Gautam, T., Geyer, M., Griessmeier, J. M., Guillemot, L., Hu, H., Jankowski, F., Johnston, S., Karastergiou, A., Karuppusamy, R., Kaur, D., Keith, M. J., Kramer, M., van Leeuwen, J., Lower, M. E., Maan, Y., McLaughlin, M. A., Meyers, B. W., Osłowski, S., Oswald, L. S., Parthasarathy, A., Pennucci, T., Posselt, B., Possenti, A., Ransom, S. M., Reardon, D. J., Ridolfi, A., Schollar, C. T. G., Serylak, M., Shaifullah, G., Shamohammadi, M., Shannon, R. M., Sobey, C., Song, X., Spiewak, R., Stairs, I. H., Stappers, B. W., van Straten, W., Szary, A., Theureau, G., Krishnan, V. Venkatraman, Weltevrede, P., Wex, N., Abbott, T. D., Adams, G. B., Burger, J. P., Gamatham, R. R. G., Gouws, M., Horn, D. M., Hugo, B., Joubert, A. F., Manley, J. R., McAlpine, K., Passmoor, S. S., Peens-Hough, A., Ramudzuli, Z. R., Rust, A., Salie, S., Schwardt, L. C., Siebrits, R., Van Tonder, G., Van Tonder, V., and Welz, M. G.
Abstract: 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 (~2.8 K/Jy) low-system temperature (~18 K at 20cm) radio array that currently operates from 580-1670 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 J0737-3039A, pulse profiles from 34 millisecond pulsars from a single 2.5h observation of the Globular cluster Terzan 5, the rotation measure of Ter5O, a 420-sigma giant pulse from the Large Magellanic Cloud pulsar PSR J0540-6919, 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 millisecond pulsars confirm that MeerKAT delivers exceptional timing. PSR J2241-5236 exhibits a jitter limit of <4 ns per hour whilst timing of PSR J1909-3744 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 1000 pulsars per day and the future deployment of S-band (1750-3500 MHz) receivers will further enhance its capabilities., Comment: 20 pages, 16 Figures, 4 Tables, accepted for publication in PASA
Published: 2020
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8. Does More Expert Adjustment Associate with Less Accurate Professional Forecasts?

Author: Franses, Ph.H.B.F. (Philip Hans), Welz, M. (Max), Franses, Ph.H.B.F. (Philip Hans), and Welz, M. (Max)
Abstract: Professional forecasters can rely on an econometric model to create their forecasts. It is usually unknown to what extent they adjust an econometric model‐based forecast. In this paper we show, while making just two simple assumptions, that it is possible to estimate the persistence and variance of the deviation of their forecasts from forecasts from an econometric model. A key feature of the data that facilitates our estimates is that we have forecast updates for the same forecast target. An illustration to consensus forecasters who give forecasts for GDP growth, inflation and unemployment for a range of countries and years suggests that the more a forecaster deviates from a prediction from an econometric model, the less accurate are the forecasts.
Published: 2020
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9. The Cash Use of the Malaysian Ringgit: Can it Be More Efficient?

Author: Franses, Philip Hans, Welz, M, Franses, Philip Hans, and Welz, M
Published: 2020

10. The MeerKAT Telescope as a Pulsar Facility: System verification and early science results from MeerTime

Author: Bailes, M., Jameson, A., Abbate, F., Barr, E. D., Bhat, N. D. R., Bondonneau, L., Burgay, M., Buchner, S. J., Camilo, F., Champion, D. J., Cognard, I., Demorest, P. B., Freire, P. C. C., Gautam, T., Geyer, M., Griessmeier, J. M., Guillemot, L., Hu, H., Jankowski, F., Johnston, S., Karastergiou, A., Karuppusamy, R., Kaur, D., Keith, M. J., Kramer, M., van Leeuwen, J., Lower, M. E., Maan, Y., McLaughlin, M. A., Meyers, B. W., Osłowski, S., Oswald, L. S., Parthasarathy, A., Pennucci, T., Posselt, B., Possenti, A., Ransom, S. M., Reardon, D. J., Ridolfi, A., Schollar, C. T. G., Serylak, M., Shaifullah, G., Shamohammadi, M., Shannon, R. M., Sobey, C., Song, X., Spiewak, R., Stairs, I. H., Stappers, B. W., van Straten, W., Szary, A., Theureau, G., Krishnan, V. Venkatraman, Weltevrede, P., Wex, N., Abbott, T. D., Adams, G. B., Burger, J. P., Gamatham, R. R. G., Gouws, M., Horn, D. M., Hugo, B., Joubert, A. F., Manley, J. R., McAlpine, K., Passmoor, S. S., Peens-Hough, A., Ramudzuli, Z. R., Rust, A., Salie, S., Schwardt, L. C., Siebrits, R., Van Tonder, G., Van Tonder, V., Welz, M. G., Bailes, M., Jameson, A., Abbate, F., Barr, E. D., Bhat, N. D. R., Bondonneau, L., Burgay, M., Buchner, S. J., Camilo, F., Champion, D. J., Cognard, I., Demorest, P. B., Freire, P. C. C., Gautam, T., Geyer, M., Griessmeier, J. M., Guillemot, L., Hu, H., Jankowski, F., Johnston, S., Karastergiou, A., Karuppusamy, R., Kaur, D., Keith, M. J., Kramer, M., van Leeuwen, J., Lower, M. E., Maan, Y., McLaughlin, M. A., Meyers, B. W., Osłowski, S., Oswald, L. S., Parthasarathy, A., Pennucci, T., Posselt, B., Possenti, A., Ransom, S. M., Reardon, D. J., Ridolfi, A., Schollar, C. T. G., Serylak, M., Shaifullah, G., Shamohammadi, M., Shannon, R. M., Sobey, C., Song, X., Spiewak, R., Stairs, I. H., Stappers, B. W., van Straten, W., Szary, A., Theureau, G., Krishnan, V. Venkatraman, Weltevrede, P., Wex, N., Abbott, T. D., Adams, G. B., Burger, J. P., Gamatham, R. R. G., Gouws, M., Horn, D. M., Hugo, B., Joubert, A. F., Manley, J. R., McAlpine, K., Passmoor, S. S., Peens-Hough, A., Ramudzuli, Z. R., Rust, A., Salie, S., Schwardt, L. C., Siebrits, R., Van Tonder, G., Van Tonder, V., and Welz, M. G.
Abstract: 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 (~2.8 K/Jy) low-system temperature (~18 K at 20cm) radio array that currently operates from 580-1670 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 J0737-3039A, pulse profiles from 34 millisecond pulsars from a single 2.5h observation of the Globular cluster Terzan 5, the rotation measure of Ter5O, a 420-sigma giant pulse from the Large Magellanic Cloud pulsar PSR J0540-6919, 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 millisecond pulsars confirm that MeerKAT delivers exceptional timing. PSR J2241-5236 exhibits a jitter limit of <4 ns per hour whilst timing of PSR J1909-3744 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 1000 pulsars per day and the future deployment of S-band (1750-3500 MHz) receivers will further enhance its capabilities., Comment: 20 pages, 16 Figures, 4 Tables, accepted for publication in PASA
Published: 2020
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11. Does More Expert Adjustment Associate with Less Accurate Professional Forecasts?

Author: Franses, Philip Hans, Welz, M, Franses, Philip Hans, and Welz, M
Published: 2020

12. Cash Use of the Taiwan Dollar

Author: Franses, Ph.H.B.F. (Philip Hans), Welz, M. (Max), Franses, Ph.H.B.F. (Philip Hans), and Welz, M. (Max)
Abstract: Two banknotes and two coins of the New Taiwan Dollar are infrequently (if at all) used in Taiwan when people make cash payments. This note examines the effect of this behavior on the efficiency of cash payments. The results are compared with the Euro, where the two highest and two lowest tokens are also rarely used. We find for Taiwan that inefficiency increases with 60.7%, while for the Euro it is only 25.3%. The main reason is that two of the rarely used coins and notes in Taiwan are in the middle of the denominational range, whereas for the Euro, these tokens concern the ends of that range.
Published: 2019
Full Text: View/download PDF

13. Cash Use of the Taiwan Dollar

Author: Franses, Ph.H.B.F. (Philip Hans), Welz, M. (Max), Franses, Ph.H.B.F. (Philip Hans), and Welz, M. (Max)
Abstract: Two banknotes and two coins of the New Taiwan Dollar are infrequently (if at all) used in Taiwan when people make cash payments. This note examines the effect of this behavior on the efficiency of cash payments. The results are compared with the Euro, where the two highest and two lowest tokens are also rarely used. We find for Taiwan that inefficiency increases with 60.7%, while for the Euro it is only 25.3%. The main reason is that two of the rarely used coins and notes in Taiwan are in the middle of the denominational range, whereas for the Euro, these tokens concern the ends of that range.
Published: 2019
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14. The 1.28 GHz MeerKAT DEEP2 Image

Author: Mauch, T., Cotton, W. D., Condon, J. J., Matthews, A. M., Abbott, T. D., Adam, R. M., Aldera, M. A., Asad, K. M. B., Bauermeister, E. F., Bennett, T. G. H., Bester, H., Botha, D. H., Brederode, L. R. S., Brits, Z. B., Buchner, S. J., Burger, J. P., Camilo, F., Chalmers, J. M., Cheetham, T., de Villiers, D., de Villiers, M. S., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fadana, G., Fanaroff, B. L., Fataar, S., February, S., Frank, B. S., Gamatham, R. R. G., Geyer, M., Goedhart, S., Gounden, S., Gumede, S. C., Heywood, I., Hlakola, M. J., Horrell, J. M. G., Hugo, B., Isaacson, A. R., Józsa, G. I. G., Jonas, J. L., Julie, R. P. M., Kapp, F. B., Kasper, V. A., Kenyon, J. S., Kotzé, P. P. A., Kriek, N., Kriel, H., Kusel, T. W., Lehmensiek, R., Loots, A., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Main, J. P. L., Malan, J. A., Manley, J. R., Marais, S. J., Martens, A., Merry, B., Millenaar, R., Mnyandu, N., Moeng, I. P. T., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T. O., Oozeer, N., Otto, A. J., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ramudzuli, Z. R., Renil, R., Richter, L. L., Robyntjies, A., Salie, S., Schollar, C. T. G., Schwardt, L. C., Serylak, M., Siebrits, R., Sirothia, S. K., Smirnov, O. M., Sofeya, L., Stone, G., Taljaard, B., Tasse, C., Theron, I. P., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., Van Tonder, V., Wallace, B. H., Welz, M. G., Williams, L. P., Xaia, B., Mauch, T., Cotton, W. D., Condon, J. J., Matthews, A. M., Abbott, T. D., Adam, R. M., Aldera, M. A., Asad, K. M. B., Bauermeister, E. F., Bennett, T. G. H., Bester, H., Botha, D. H., Brederode, L. R. S., Brits, Z. B., Buchner, S. J., Burger, J. P., Camilo, F., Chalmers, J. M., Cheetham, T., de Villiers, D., de Villiers, M. S., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fadana, G., Fanaroff, B. L., Fataar, S., February, S., Frank, B. S., Gamatham, R. R. G., Geyer, M., Goedhart, S., Gounden, S., Gumede, S. C., Heywood, I., Hlakola, M. J., Horrell, J. M. G., Hugo, B., Isaacson, A. R., Józsa, G. I. G., Jonas, J. L., Julie, R. P. M., Kapp, F. B., Kasper, V. A., Kenyon, J. S., Kotzé, P. P. A., Kriek, N., Kriel, H., Kusel, T. W., Lehmensiek, R., Loots, A., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Main, J. P. L., Malan, J. A., Manley, J. R., Marais, S. J., Martens, A., Merry, B., Millenaar, R., Mnyandu, N., Moeng, I. P. T., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T. O., Oozeer, N., Otto, A. J., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ramudzuli, Z. R., Renil, R., Richter, L. L., Robyntjies, A., Salie, S., Schollar, C. T. G., Schwardt, L. C., Serylak, M., Siebrits, R., Sirothia, S. K., Smirnov, O. M., Sofeya, L., Stone, G., Taljaard, B., Tasse, C., Theron, I. P., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., Van Tonder, V., Wallace, B. H., Welz, M. G., Williams, L. P., and Xaia, B.
Abstract: We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one $\approx 68'$ FWHM primary beam area with $7.6''$ FWHM resolution and $0.55 \pm 0.01$ $\mu$Jy/beam rms noise. Its J2000 center position $\alpha=04^h 13^m 26.4^s$, $\delta=-80^\circ 00' 00''$ was selected to minimize artifacts caused by bright sources. We introduce the new 64-element MeerKAT array and describe commissioning observations to measure the primary beam attenuation pattern, estimate telescope pointing errors, and pinpoint $(u,v)$ coordinate errors caused by offsets in frequency or time. We constructed a 1.4 GHz differential source count by combining a power-law count fit to the DEEP2 confusion $P(D)$ distribution from $0.25$ to $10$ $\mu$Jy with counts of individual DEEP2 sources between $10$ $\mu$Jy and $2.5$ mJy. Most sources fainter than $S \sim 100$ $\mu$Jy are distant star-forming galaxies obeying the FIR/radio correlation, and sources stronger than $0.25$ $\mu$Jy account for $\sim93\%$ of the radio background produced by star-forming galaxies. For the first time, the DEEP2 source count has reached the depth needed to reveal the majority of the star formation history of the universe. A pure luminosity evolution of the 1.4 GHz local luminosity function consistent with the Madau & Dickinson (2014) model for the evolution of star-forming galaxies based on UV and infrared data underpredicts our 1.4 GHz source count in the range $-5 \lesssim \log[S(\mathrm{Jy})] \lesssim -4$., Comment: 20 pages, 18 figures. Accepted for publication in ApJ
Published: 2019
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15. Inflation of 430-parsec bipolar radio bubbles in the Galactic Centre by an energetic event

Author: Heywood, I., Camilo, F., Cotton, W. D., Yusef-Zadeh, F., Abbott, T. D., Adam, R. M., Aldera, M. A., Bauermeister, E. F., Booth, R. S., Botha, A. G., Botha, D. H., Brederode, L. R. S., Brits, Z. B., Buchner, S. J., Burger, J. P., Chalmers, J. M., Cheetham, T., de Villiers, D., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., Foley, A. R., Fourie, D. J., Gamatham, R. R. G., Goedhart, S., Gounden, S., Hlakola, M. J., Hoek, C. J., Hokwana, A., Horn, D. M., Horrell, J. M. G., Hugo, B., Isaacson, A. R., Jonas, J. L., Jordaan, J. D. B. L., Joubert, A. F., Józsa, G. I. G., Julie, R. P. M., Kapp, F. B., Kenyon, J. S., Kotzé, P. P. A., Kriel, H., Kusel, T. W., Lehmensiek, R., Liebenberg, D., Loots, A., Lord, R. T., Lunsky, B. M., Macfarlane, P. S., Magnus, L. G., Magozore, C. M., Mahgoub, O., Main, J. P. L., Malan, J. A., Malgas, R. D., Manley, J. R., Maree, M. D. J., Merry, B., Millenaar, R., Mnyandu, N., Moeng, I. P. T., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Oozeer, N., Otto, A. J., Passmoor, S. S., Pate, A. A., Peens-Hough, A., Perkins, S. J., Ratcliffe, S. M., Renil, R., Rust, A., Salie, S., Schwardt, L. C., Serylak, M., Siebrits, R., Sirothia, S. K., Smirnov, O. M., Sofeya, L., Swart, P. S., Tasse, C., Taylor, D. T., Theron, I. P., Thorat, K., Tiplad, A. J., Tshongweni, S., van Balla, T. J., van der Byl, A., van der Merwe, C., van Dyk, C. L., Van Rooyen, R., Van Tonder, V., Van Wyk, R., Wallace, B. H., Welz, M. G., Williams, L. P., Heywood, I., Camilo, F., Cotton, W. D., Yusef-Zadeh, F., Abbott, T. D., Adam, R. M., Aldera, M. A., Bauermeister, E. F., Booth, R. S., Botha, A. G., Botha, D. H., Brederode, L. R. S., Brits, Z. B., Buchner, S. J., Burger, J. P., Chalmers, J. M., Cheetham, T., de Villiers, D., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., Foley, A. R., Fourie, D. J., Gamatham, R. R. G., Goedhart, S., Gounden, S., Hlakola, M. J., Hoek, C. J., Hokwana, A., Horn, D. M., Horrell, J. M. G., Hugo, B., Isaacson, A. R., Jonas, J. L., Jordaan, J. D. B. L., Joubert, A. F., Józsa, G. I. G., Julie, R. P. M., Kapp, F. B., Kenyon, J. S., Kotzé, P. P. A., Kriel, H., Kusel, T. W., Lehmensiek, R., Liebenberg, D., Loots, A., Lord, R. T., Lunsky, B. M., Macfarlane, P. S., Magnus, L. G., Magozore, C. M., Mahgoub, O., Main, J. P. L., Malan, J. A., Malgas, R. D., Manley, J. R., Maree, M. D. J., Merry, B., Millenaar, R., Mnyandu, N., Moeng, I. P. T., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Oozeer, N., Otto, A. J., Passmoor, S. S., Pate, A. A., Peens-Hough, A., Perkins, S. J., Ratcliffe, S. M., Renil, R., Rust, A., Salie, S., Schwardt, L. C., Serylak, M., Siebrits, R., Sirothia, S. K., Smirnov, O. M., Sofeya, L., Swart, P. S., Tasse, C., Taylor, D. T., Theron, I. P., Thorat, K., Tiplad, A. J., Tshongweni, S., van Balla, T. J., van der Byl, A., van der Merwe, C., van Dyk, C. L., Van Rooyen, R., Van Tonder, V., Van Wyk, R., Wallace, B. H., Welz, M. G., and Williams, L. P.
Abstract: The Galactic Centre contains a supermassive black hole with a mass of 4 million suns within an environment that differs markedly from that of the Galactic disk. While the black hole is essentially quiescent in the broader context of active galactic nuclei, X-ray observations have provided evidence for energetic outbursts from its surroundings. Also, while the levels of star formation in the Galactic Centre have been approximately constant over the last few hundred Myr, there is evidence of elevated short-duration bursts, strongly influenced by interaction of the black hole with the enhanced gas density present within the ring-like Central Molecular Zone at Galactic longitude |l| < 0.7 degrees and latitude |b| < 0.2 degrees. The inner 200 pc region is characterized by large amounts of warm molecular gas, a high cosmic ray ionization rate, unusual gas chemistry, enhanced synchrotron emission, and a multitude of radio-emitting magnetised filaments, the origin of which has not been established. Here we report radio imaging that reveals bipolar bubbles spanning 1 degree x 3 degrees (140 parsecs x 430 parsecs), extending above and below the Galactic plane and apparently associated with the Galactic Centre. The structure is edge-brightened and bounded, with symmetry implying creation by an energetic event in the Galactic Centre. We estimate the age of the bubbles to be a few million years, with a total energy of 7 x 10^52 ergs. We postulate that the progenitor event was a major contributor to the increased cosmic-ray density in the Galactic Centre, and is in turn the principal source of the relativistic particles required to power the synchrotron emission of the radio filaments within and in the vicinity of the bubble cavities., Comment: 25 pages, 3 figures, 3 tables, authors' version of a Letter published in Nature on 11 September 2019
Published: 2019
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16. Cash use of the Taiwan dollar: Is it efficient?

Author: Franses, Ph.H.B.F. (Philip Hans), Welz, M., Franses, Ph.H.B.F. (Philip Hans), and Welz, M.
Abstract: Two banknotes and two coins of the New Taiwan Dollar are infrequently (if at all) used in Taiwan when people make cash payments. This note examines the effect of this behavior on the efficiency of cash payments. The results are compared with the Euro, where the two highest and two lowest tokens are also rarely used. We find for Taiwan that inefficiency increases with 60.7%, while for the Euro it is only 25.3%. The main reason is that two of the rarely used coins and notes in Taiwan are in the middle of the denominational range, whereas for the Euro, these tokens concern the ends of that range.
Published: 2019

17. The 1.28 GHz MeerKAT DEEP2 Image

Author: Mauch, T., Cotton, W. D., Condon, J. J., Matthews, A. M., Abbott, T. D., Adam, R. M., Aldera, M. A., Asad, K. M. B., Bauermeister, E. F., Bennett, T. G. H., Bester, H., Botha, D. H., Brederode, L. R. S., Brits, Z. B., Buchner, S. J., Burger, J. P., Camilo, F., Chalmers, J. M., Cheetham, T., de Villiers, D., de Villiers, M. S., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fadana, G., Fanaroff, B. L., Fataar, S., February, S., Frank, B. S., Gamatham, R. R. G., Geyer, M., Goedhart, S., Gounden, S., Gumede, S. C., Heywood, I., Hlakola, M. J., Horrell, J. M. G., Hugo, B., Isaacson, A. R., Józsa, G. I. G., Jonas, J. L., Julie, R. P. M., Kapp, F. B., Kasper, V. A., Kenyon, J. S., Kotzé, P. P. A., Kriek, N., Kriel, H., Kusel, T. W., Lehmensiek, R., Loots, A., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Main, J. P. L., Malan, J. A., Manley, J. R., Marais, S. J., Martens, A., Merry, B., Millenaar, R., Mnyandu, N., Moeng, I. P. T., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T. O., Oozeer, N., Otto, A. J., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ramudzuli, Z. R., Renil, R., Richter, L. L., Robyntjies, A., Salie, S., Schollar, C. T. G., Schwardt, L. C., Serylak, M., Siebrits, R., Sirothia, S. K., Smirnov, O. M., Sofeya, L., Stone, G., Taljaard, B., Tasse, C., Theron, I. P., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., Van Tonder, V., Wallace, B. H., Welz, M. G., Williams, L. P., Xaia, B., Mauch, T., Cotton, W. D., Condon, J. J., Matthews, A. M., Abbott, T. D., Adam, R. M., Aldera, M. A., Asad, K. M. B., Bauermeister, E. F., Bennett, T. G. H., Bester, H., Botha, D. H., Brederode, L. R. S., Brits, Z. B., Buchner, S. J., Burger, J. P., Camilo, F., Chalmers, J. M., Cheetham, T., de Villiers, D., de Villiers, M. S., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fadana, G., Fanaroff, B. L., Fataar, S., February, S., Frank, B. S., Gamatham, R. R. G., Geyer, M., Goedhart, S., Gounden, S., Gumede, S. C., Heywood, I., Hlakola, M. J., Horrell, J. M. G., Hugo, B., Isaacson, A. R., Józsa, G. I. G., Jonas, J. L., Julie, R. P. M., Kapp, F. B., Kasper, V. A., Kenyon, J. S., Kotzé, P. P. A., Kriek, N., Kriel, H., Kusel, T. W., Lehmensiek, R., Loots, A., Lord, R. T., Lunsky, B. M., Madisa, K., Magnus, L. G., Main, J. P. L., Malan, J. A., Manley, J. R., Marais, S. J., Martens, A., Merry, B., Millenaar, R., Mnyandu, N., Moeng, I. P. T., Mokone, O. J., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Ngoasheng, K. J., Ockards, M. T. O., Oozeer, N., Otto, A. J., Patel, A. A., Peens-Hough, A., Perkins, S. J., Ramaila, A. J. T., Ramudzuli, Z. R., Renil, R., Richter, L. L., Robyntjies, A., Salie, S., Schollar, C. T. G., Schwardt, L. C., Serylak, M., Siebrits, R., Sirothia, S. K., Smirnov, O. M., Sofeya, L., Stone, G., Taljaard, B., Tasse, C., Theron, I. P., Tiplady, A. J., Toruvanda, O., Twum, S. N., van Balla, T. J., van der Byl, A., van der Merwe, C., Van Tonder, V., Wallace, B. H., Welz, M. G., Williams, L. P., and Xaia, B.
Abstract: We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one $\approx 68'$ FWHM primary beam area with $7.6''$ FWHM resolution and $0.55 \pm 0.01$ $\mu$Jy/beam rms noise. Its J2000 center position $\alpha=04^h 13^m 26.4^s$, $\delta=-80^\circ 00' 00''$ was selected to minimize artifacts caused by bright sources. We introduce the new 64-element MeerKAT array and describe commissioning observations to measure the primary beam attenuation pattern, estimate telescope pointing errors, and pinpoint $(u,v)$ coordinate errors caused by offsets in frequency or time. We constructed a 1.4 GHz differential source count by combining a power-law count fit to the DEEP2 confusion $P(D)$ distribution from $0.25$ to $10$ $\mu$Jy with counts of individual DEEP2 sources between $10$ $\mu$Jy and $2.5$ mJy. Most sources fainter than $S \sim 100$ $\mu$Jy are distant star-forming galaxies obeying the FIR/radio correlation, and sources stronger than $0.25$ $\mu$Jy account for $\sim93\%$ of the radio background produced by star-forming galaxies. For the first time, the DEEP2 source count has reached the depth needed to reveal the majority of the star formation history of the universe. A pure luminosity evolution of the 1.4 GHz local luminosity function consistent with the Madau & Dickinson (2014) model for the evolution of star-forming galaxies based on UV and infrared data underpredicts our 1.4 GHz source count in the range $-5 \lesssim \log[S(\mathrm{Jy})] \lesssim -4$., Comment: 20 pages, 18 figures. Accepted for publication in ApJ
Published: 2019
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18. Inflation of 430-parsec bipolar radio bubbles in the Galactic Centre by an energetic event

Author: Heywood, I., Camilo, F., Cotton, W. D., Yusef-Zadeh, F., Abbott, T. D., Adam, R. M., Aldera, M. A., Bauermeister, E. F., Booth, R. S., Botha, A. G., Botha, D. H., Brederode, L. R. S., Brits, Z. B., Buchner, S. J., Burger, J. P., Chalmers, J. M., Cheetham, T., de Villiers, D., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., Foley, A. R., Fourie, D. J., Gamatham, R. R. G., Goedhart, S., Gounden, S., Hlakola, M. J., Hoek, C. J., Hokwana, A., Horn, D. M., Horrell, J. M. G., Hugo, B., Isaacson, A. R., Jonas, J. L., Jordaan, J. D. B. L., Joubert, A. F., Józsa, G. I. G., Julie, R. P. M., Kapp, F. B., Kenyon, J. S., Kotzé, P. P. A., Kriel, H., Kusel, T. W., Lehmensiek, R., Liebenberg, D., Loots, A., Lord, R. T., Lunsky, B. M., Macfarlane, P. S., Magnus, L. G., Magozore, C. M., Mahgoub, O., Main, J. P. L., Malan, J. A., Malgas, R. D., Manley, J. R., Maree, M. D. J., Merry, B., Millenaar, R., Mnyandu, N., Moeng, I. P. T., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Oozeer, N., Otto, A. J., Passmoor, S. S., Pate, A. A., Peens-Hough, A., Perkins, S. J., Ratcliffe, S. M., Renil, R., Rust, A., Salie, S., Schwardt, L. C., Serylak, M., Siebrits, R., Sirothia, S. K., Smirnov, O. M., Sofeya, L., Swart, P. S., Tasse, C., Taylor, D. T., Theron, I. P., Thorat, K., Tiplad, A. J., Tshongweni, S., van Balla, T. J., van der Byl, A., van der Merwe, C., van Dyk, C. L., Van Rooyen, R., Van Tonder, V., Van Wyk, R., Wallace, B. H., Welz, M. G., Williams, L. P., Heywood, I., Camilo, F., Cotton, W. D., Yusef-Zadeh, F., Abbott, T. D., Adam, R. M., Aldera, M. A., Bauermeister, E. F., Booth, R. S., Botha, A. G., Botha, D. H., Brederode, L. R. S., Brits, Z. B., Buchner, S. J., Burger, J. P., Chalmers, J. M., Cheetham, T., de Villiers, D., Dikgale-Mahlakoana, M. A., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B. L., Foley, A. R., Fourie, D. J., Gamatham, R. R. G., Goedhart, S., Gounden, S., Hlakola, M. J., Hoek, C. J., Hokwana, A., Horn, D. M., Horrell, J. M. G., Hugo, B., Isaacson, A. R., Jonas, J. L., Jordaan, J. D. B. L., Joubert, A. F., Józsa, G. I. G., Julie, R. P. M., Kapp, F. B., Kenyon, J. S., Kotzé, P. P. A., Kriel, H., Kusel, T. W., Lehmensiek, R., Liebenberg, D., Loots, A., Lord, R. T., Lunsky, B. M., Macfarlane, P. S., Magnus, L. G., Magozore, C. M., Mahgoub, O., Main, J. P. L., Malan, J. A., Malgas, R. D., Manley, J. R., Maree, M. D. J., Merry, B., Millenaar, R., Mnyandu, N., Moeng, I. P. T., Monama, T. E., Mphego, M. C., New, W. S., Ngcebetsha, B., Oozeer, N., Otto, A. J., Passmoor, S. S., Pate, A. A., Peens-Hough, A., Perkins, S. J., Ratcliffe, S. M., Renil, R., Rust, A., Salie, S., Schwardt, L. C., Serylak, M., Siebrits, R., Sirothia, S. K., Smirnov, O. M., Sofeya, L., Swart, P. S., Tasse, C., Taylor, D. T., Theron, I. P., Thorat, K., Tiplad, A. J., Tshongweni, S., van Balla, T. J., van der Byl, A., van der Merwe, C., van Dyk, C. L., Van Rooyen, R., Van Tonder, V., Van Wyk, R., Wallace, B. H., Welz, M. G., and Williams, L. P.
Abstract: The Galactic Centre contains a supermassive black hole with a mass of 4 million suns within an environment that differs markedly from that of the Galactic disk. While the black hole is essentially quiescent in the broader context of active galactic nuclei, X-ray observations have provided evidence for energetic outbursts from its surroundings. Also, while the levels of star formation in the Galactic Centre have been approximately constant over the last few hundred Myr, there is evidence of elevated short-duration bursts, strongly influenced by interaction of the black hole with the enhanced gas density present within the ring-like Central Molecular Zone at Galactic longitude |l| < 0.7 degrees and latitude |b| < 0.2 degrees. The inner 200 pc region is characterized by large amounts of warm molecular gas, a high cosmic ray ionization rate, unusual gas chemistry, enhanced synchrotron emission, and a multitude of radio-emitting magnetised filaments, the origin of which has not been established. Here we report radio imaging that reveals bipolar bubbles spanning 1 degree x 3 degrees (140 parsecs x 430 parsecs), extending above and below the Galactic plane and apparently associated with the Galactic Centre. The structure is edge-brightened and bounded, with symmetry implying creation by an energetic event in the Galactic Centre. We estimate the age of the bubbles to be a few million years, with a total energy of 7 x 10^52 ergs. We postulate that the progenitor event was a major contributor to the increased cosmic-ray density in the Galactic Centre, and is in turn the principal source of the relativistic particles required to power the synchrotron emission of the radio filaments within and in the vicinity of the bubble cavities., Comment: 25 pages, 3 figures, 3 tables, authors' version of a Letter published in Nature on 11 September 2019
Published: 2019
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19. Cash use of the Taiwan dollar. Is it efficient

Author: Franses, Philip Hans, Welz, M, Franses, Philip Hans, and Welz, M
Published: 2019

20. Cash use of the Taiwan dollar: Is it efficient?

Author: Franses, Philip Hans, Welz, M, Franses, Philip Hans, and Welz, M
Published: 2019

21. Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

Author: Camilo, F., Scholz, P., Serylak, M., Buchner, S., Merryfield, M., Kaspi, V. M., Archibald, R. F., Bailes, M., Jameson, A., van Straten, W., Sarkissian, J., Reynolds, J. E., Johnston, S., Hobbs, G., Abbott, T. D., Adam, R. M., Adams, G. B., Alberts, T., Andreas, R., Asad, K. M. B., Baker, D. E., Baloyi, T., Bauermeister, E. F., Baxana, T., Bennett, T. G. H., Bernardi, G., Booisen, D., Booth, R. S., Botha, D. H., Boyana, L., Brederode, L. R. S., Burger, J. P., Cheetham, T., Conradie, J., Conradie, J. P., Davidson, D. B., de Bruin, G., de Swardt, B., de Villiers, C., de Villiers, D. I. L., de Villiers, M. S., de Villiers, W., de Waal, C., Dikgale, M. A., Toit, G. du, Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B., Fataar, S., Foley, A. R., Foster, G., Fourie, D., Gamatham, R., Gatsi, T., Geschke, R., Goedhart, S., Grobler, T. L., Gumede, S. C., Hlakola, M. J., Hokwana, A., Hoorn, D. H., Horn, D., Horrell, J., Hugo, B., Isaacson, A., Jacobs, O., van Rensburg, J. P. Jansen, Jonas, J. L., Jordaan, B., Joubert, A., Joubert, F., Jozsa, G. I. G., Julie, R., Julius, C. C., Kapp, F., Karastergiou, A., Karels, F., Kariseb, M., Karuppusamy, R., Kasper, V., Knox-Davies, E. C., Koch, D., Kotze, P. P. A., Krebs, A., Kriek, N., Kriel, H., Kusel, T., Lamoor, S., Lehmensiek, R., Liebenberg, D., Liebenberg, I., Lord, R. T., Lunsky, B., Mabombo, N., Macdonald, T., Macfarlane, P., Madisa, K., Mafhungo, L., Magnus, L. G., Magozore, C., Mahgoub, O., Main, J. P. L., Makhathini, S., Malan, J. A., Malgas, P., Manley, J. R., Manzini, M., Marais, L., Marais, N., Marais, S. J., Maree, M., Martens, A., Matshawule, S. D., Matthysen, N., Mauch, T., Nally, L. D. Mc, Merry, B., Millenaar, R. P., Mjikelo, C., Mkhabela, N., Mnyandu, N., Moeng, I. T., Mokone, O. J., Monama, T. E., Montshiwa, K., Moss, V., Mphego, M., New, W., Ngcebetsha, B., Ngoasheng, K., Niehaus, H., Ntuli, P., Nzama, A., Obies, F., Obrocka, M., Ockards, M. T., Olyn, C., Oozeer, N., Otto, A. J., Padayachee, Y., Passmoor, S., Patel, A. A., Paula, S., Peens-Hough, A., Pholoholo, B., Prozesky, P., Rakoma, S., Ramaila, A. J. T., Rammala, I., Ramudzuli, Z. R., Rasivhaga, M., Ratcliffe, S., Reader, H. C., Renil, R., Richter, L., Robyntjies, A., Rosekrans, D., Rust, A., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L., Seranyane, S., Sethosa, G., Sharpe, C., Siebrits, R., Sirothia, S. K., Slabber, M. J., Smirnov, O., Smith, S., Sofeya, L., Songqumase, N., Spann, R., Stappers, B., Steyn, D., Steyn, T. J., Strong, R., Struthers, A., Stuart, C., Sunnylall, P., Swart, P. S., Taljaard, B., Tasse, C., Taylor, G., Theron, I. P., Thondikulam, V., Thorat, K., Tiplady, A., Toruvanda, O., van Aardt, J., van Balla, T., Heever, L. van den, van der Byl, A., van der Merwe, C., van der Merwe, P., van Niekerk, P. C., van Rooyen, R., van Staden, J. P., van Tonder, V., van Wyk, R., Wait, I., Walker, A. L., Wallace, B., Welz, M., Williams, L. P., Xaia, B., Young, N., Zitha, S., Camilo, F., Scholz, P., Serylak, M., Buchner, S., Merryfield, M., Kaspi, V. M., Archibald, R. F., Bailes, M., Jameson, A., van Straten, W., Sarkissian, J., Reynolds, J. E., Johnston, S., Hobbs, G., Abbott, T. D., Adam, R. M., Adams, G. B., Alberts, T., Andreas, R., Asad, K. M. B., Baker, D. E., Baloyi, T., Bauermeister, E. F., Baxana, T., Bennett, T. G. H., Bernardi, G., Booisen, D., Booth, R. S., Botha, D. H., Boyana, L., Brederode, L. R. S., Burger, J. P., Cheetham, T., Conradie, J., Conradie, J. P., Davidson, D. B., de Bruin, G., de Swardt, B., de Villiers, C., de Villiers, D. I. L., de Villiers, M. S., de Villiers, W., de Waal, C., Dikgale, M. A., Toit, G. du, Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B., Fataar, S., Foley, A. R., Foster, G., Fourie, D., Gamatham, R., Gatsi, T., Geschke, R., Goedhart, S., Grobler, T. L., Gumede, S. C., Hlakola, M. J., Hokwana, A., Hoorn, D. H., Horn, D., Horrell, J., Hugo, B., Isaacson, A., Jacobs, O., van Rensburg, J. P. Jansen, Jonas, J. L., Jordaan, B., Joubert, A., Joubert, F., Jozsa, G. I. G., Julie, R., Julius, C. C., Kapp, F., Karastergiou, A., Karels, F., Kariseb, M., Karuppusamy, R., Kasper, V., Knox-Davies, E. C., Koch, D., Kotze, P. P. A., Krebs, A., Kriek, N., Kriel, H., Kusel, T., Lamoor, S., Lehmensiek, R., Liebenberg, D., Liebenberg, I., Lord, R. T., Lunsky, B., Mabombo, N., Macdonald, T., Macfarlane, P., Madisa, K., Mafhungo, L., Magnus, L. G., Magozore, C., Mahgoub, O., Main, J. P. L., Makhathini, S., Malan, J. A., Malgas, P., Manley, J. R., Manzini, M., Marais, L., Marais, N., Marais, S. J., Maree, M., Martens, A., Matshawule, S. D., Matthysen, N., Mauch, T., Nally, L. D. Mc, Merry, B., Millenaar, R. P., Mjikelo, C., Mkhabela, N., Mnyandu, N., Moeng, I. T., Mokone, O. J., Monama, T. E., Montshiwa, K., Moss, V., Mphego, M., New, W., Ngcebetsha, B., Ngoasheng, K., Niehaus, H., Ntuli, P., Nzama, A., Obies, F., Obrocka, M., Ockards, M. T., Olyn, C., Oozeer, N., Otto, A. J., Padayachee, Y., Passmoor, S., Patel, A. A., Paula, S., Peens-Hough, A., Pholoholo, B., Prozesky, P., Rakoma, S., Ramaila, A. J. T., Rammala, I., Ramudzuli, Z. R., Rasivhaga, M., Ratcliffe, S., Reader, H. C., Renil, R., Richter, L., Robyntjies, A., Rosekrans, D., Rust, A., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L., Seranyane, S., Sethosa, G., Sharpe, C., Siebrits, R., Sirothia, S. K., Slabber, M. J., Smirnov, O., Smith, S., Sofeya, L., Songqumase, N., Spann, R., Stappers, B., Steyn, D., Steyn, T. J., Strong, R., Struthers, A., Stuart, C., Sunnylall, P., Swart, P. S., Taljaard, B., Tasse, C., Taylor, G., Theron, I. P., Thondikulam, V., Thorat, K., Tiplady, A., Toruvanda, O., van Aardt, J., van Balla, T., Heever, L. van den, van der Byl, A., van der Merwe, C., van der Merwe, P., van Niekerk, P. C., van Rooyen, R., van Staden, J. P., van Tonder, V., van Wyk, R., Wait, I., Walker, A. L., Wallace, B., Welz, M., Williams, L. P., Xaia, B., Young, N., and Zitha, S.
Abstract: New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100x larger than during its dormant state. The X-ray flux one month after reactivation was at least 800x larger than during quiescence, and has been decaying exponentially on a 111+/-19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation., Comment: Published in ApJ (2018 April 5); 13 pages, 4 figures
Published: 2018
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22. Perforin inhibition protects from lethal endothelial damage during fulminant viral hepatitis

Author: Welz, M, Eickhoff, S, Abdullah, Z, Trebicka, J, Gartlan, KH, Spicer, JA, Demetris, AJ, Akhlaghi, H, Anton, M, Manske, K, Zehn, D, Nieswandt, B, Kurts, C, Trapani, JA, Knolle, P, Wohlleber, D, Kastenmueller, W, Welz, M, Eickhoff, S, Abdullah, Z, Trebicka, J, Gartlan, KH, Spicer, JA, Demetris, AJ, Akhlaghi, H, Anton, M, Manske, K, Zehn, D, Nieswandt, B, Kurts, C, Trapani, JA, Knolle, P, Wohlleber, D, and Kastenmueller, W
Abstract: CD8 T cells protect the liver against viral infection, but can also cause severe liver damage that may even lead to organ failure. Given the lack of mechanistic insights and specific treatment options in patients with acute fulminant hepatitis, we develop a mouse model reflecting a severe acute virus-induced CD8 T cell-mediated hepatitis. Here we show that antigen-specific CD8 T cells induce liver damage in a perforin-dependent manner, yet liver failure is not caused by effector responses targeting virus-infected hepatocytes alone. Additionally, CD8 T cell mediated elimination of cross-presenting liver sinusoidal endothelial cells causes endothelial damage that leads to a dramatically impaired sinusoidal perfusion and indirectly to hepatocyte death. With the identification of perforin-mediated killing as a critical pathophysiologic mechanism of liver failure and the protective function of a new class of perforin inhibitor, our study opens new potential therapeutic angles for fulminant viral hepatitis.
Published: 2018

23. Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

Author: Camilo, F., Scholz, P., Serylak, M., Buchner, S., Merryfield, M., Kaspi, V. M., Archibald, R. F., Bailes, M., Jameson, A., van Straten, W., Sarkissian, J., Reynolds, J. E., Johnston, S., Hobbs, G., Abbott, T. D., Adam, R. M., Adams, G. B., Alberts, T., Andreas, R., Asad, K. M. B., Baker, D. E., Baloyi, T., Bauermeister, E. F., Baxana, T., Bennett, T. G. H., Bernardi, G., Booisen, D., Booth, R. S., Botha, D. H., Boyana, L., Brederode, L. R. S., Burger, J. P., Cheetham, T., Conradie, J., Conradie, J. P., Davidson, D. B., de Bruin, G., de Swardt, B., de Villiers, C., de Villiers, D. I. L., de Villiers, M. S., de Villiers, W., de Waal, C., Dikgale, M. A., Toit, G. du, Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B., Fataar, S., Foley, A. R., Foster, G., Fourie, D., Gamatham, R., Gatsi, T., Geschke, R., Goedhart, S., Grobler, T. L., Gumede, S. C., Hlakola, M. J., Hokwana, A., Hoorn, D. H., Horn, D., Horrell, J., Hugo, B., Isaacson, A., Jacobs, O., van Rensburg, J. P. Jansen, Jonas, J. L., Jordaan, B., Joubert, A., Joubert, F., Jozsa, G. I. G., Julie, R., Julius, C. C., Kapp, F., Karastergiou, A., Karels, F., Kariseb, M., Karuppusamy, R., Kasper, V., Knox-Davies, E. C., Koch, D., Kotze, P. P. A., Krebs, A., Kriek, N., Kriel, H., Kusel, T., Lamoor, S., Lehmensiek, R., Liebenberg, D., Liebenberg, I., Lord, R. T., Lunsky, B., Mabombo, N., Macdonald, T., Macfarlane, P., Madisa, K., Mafhungo, L., Magnus, L. G., Magozore, C., Mahgoub, O., Main, J. P. L., Makhathini, S., Malan, J. A., Malgas, P., Manley, J. R., Manzini, M., Marais, L., Marais, N., Marais, S. J., Maree, M., Martens, A., Matshawule, S. D., Matthysen, N., Mauch, T., Nally, L. D. Mc, Merry, B., Millenaar, R. P., Mjikelo, C., Mkhabela, N., Mnyandu, N., Moeng, I. T., Mokone, O. J., Monama, T. E., Montshiwa, K., Moss, V., Mphego, M., New, W., Ngcebetsha, B., Ngoasheng, K., Niehaus, H., Ntuli, P., Nzama, A., Obies, F., Obrocka, M., Ockards, M. T., Olyn, C., Oozeer, N., Otto, A. J., Padayachee, Y., Passmoor, S., Patel, A. A., Paula, S., Peens-Hough, A., Pholoholo, B., Prozesky, P., Rakoma, S., Ramaila, A. J. T., Rammala, I., Ramudzuli, Z. R., Rasivhaga, M., Ratcliffe, S., Reader, H. C., Renil, R., Richter, L., Robyntjies, A., Rosekrans, D., Rust, A., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L., Seranyane, S., Sethosa, G., Sharpe, C., Siebrits, R., Sirothia, S. K., Slabber, M. J., Smirnov, O., Smith, S., Sofeya, L., Songqumase, N., Spann, R., Stappers, B., Steyn, D., Steyn, T. J., Strong, R., Struthers, A., Stuart, C., Sunnylall, P., Swart, P. S., Taljaard, B., Tasse, C., Taylor, G., Theron, I. P., Thondikulam, V., Thorat, K., Tiplady, A., Toruvanda, O., van Aardt, J., van Balla, T., Heever, L. van den, van der Byl, A., van der Merwe, C., van der Merwe, P., van Niekerk, P. C., van Rooyen, R., van Staden, J. P., van Tonder, V., van Wyk, R., Wait, I., Walker, A. L., Wallace, B., Welz, M., Williams, L. P., Xaia, B., Young, N., Zitha, S., Camilo, F., Scholz, P., Serylak, M., Buchner, S., Merryfield, M., Kaspi, V. M., Archibald, R. F., Bailes, M., Jameson, A., van Straten, W., Sarkissian, J., Reynolds, J. E., Johnston, S., Hobbs, G., Abbott, T. D., Adam, R. M., Adams, G. B., Alberts, T., Andreas, R., Asad, K. M. B., Baker, D. E., Baloyi, T., Bauermeister, E. F., Baxana, T., Bennett, T. G. H., Bernardi, G., Booisen, D., Booth, R. S., Botha, D. H., Boyana, L., Brederode, L. R. S., Burger, J. P., Cheetham, T., Conradie, J., Conradie, J. P., Davidson, D. B., de Bruin, G., de Swardt, B., de Villiers, C., de Villiers, D. I. L., de Villiers, M. S., de Villiers, W., de Waal, C., Dikgale, M. A., Toit, G. du, Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B., Fataar, S., Foley, A. R., Foster, G., Fourie, D., Gamatham, R., Gatsi, T., Geschke, R., Goedhart, S., Grobler, T. L., Gumede, S. C., Hlakola, M. J., Hokwana, A., Hoorn, D. H., Horn, D., Horrell, J., Hugo, B., Isaacson, A., Jacobs, O., van Rensburg, J. P. Jansen, Jonas, J. L., Jordaan, B., Joubert, A., Joubert, F., Jozsa, G. I. G., Julie, R., Julius, C. C., Kapp, F., Karastergiou, A., Karels, F., Kariseb, M., Karuppusamy, R., Kasper, V., Knox-Davies, E. C., Koch, D., Kotze, P. P. A., Krebs, A., Kriek, N., Kriel, H., Kusel, T., Lamoor, S., Lehmensiek, R., Liebenberg, D., Liebenberg, I., Lord, R. T., Lunsky, B., Mabombo, N., Macdonald, T., Macfarlane, P., Madisa, K., Mafhungo, L., Magnus, L. G., Magozore, C., Mahgoub, O., Main, J. P. L., Makhathini, S., Malan, J. A., Malgas, P., Manley, J. R., Manzini, M., Marais, L., Marais, N., Marais, S. J., Maree, M., Martens, A., Matshawule, S. D., Matthysen, N., Mauch, T., Nally, L. D. Mc, Merry, B., Millenaar, R. P., Mjikelo, C., Mkhabela, N., Mnyandu, N., Moeng, I. T., Mokone, O. J., Monama, T. E., Montshiwa, K., Moss, V., Mphego, M., New, W., Ngcebetsha, B., Ngoasheng, K., Niehaus, H., Ntuli, P., Nzama, A., Obies, F., Obrocka, M., Ockards, M. T., Olyn, C., Oozeer, N., Otto, A. J., Padayachee, Y., Passmoor, S., Patel, A. A., Paula, S., Peens-Hough, A., Pholoholo, B., Prozesky, P., Rakoma, S., Ramaila, A. J. T., Rammala, I., Ramudzuli, Z. R., Rasivhaga, M., Ratcliffe, S., Reader, H. C., Renil, R., Richter, L., Robyntjies, A., Rosekrans, D., Rust, A., Salie, S., Sambu, N., Schollar, C. T. G., Schwardt, L., Seranyane, S., Sethosa, G., Sharpe, C., Siebrits, R., Sirothia, S. K., Slabber, M. J., Smirnov, O., Smith, S., Sofeya, L., Songqumase, N., Spann, R., Stappers, B., Steyn, D., Steyn, T. J., Strong, R., Struthers, A., Stuart, C., Sunnylall, P., Swart, P. S., Taljaard, B., Tasse, C., Taylor, G., Theron, I. P., Thondikulam, V., Thorat, K., Tiplady, A., Toruvanda, O., van Aardt, J., van Balla, T., Heever, L. van den, van der Byl, A., van der Merwe, C., van der Merwe, P., van Niekerk, P. C., van Rooyen, R., van Staden, J. P., van Tonder, V., van Wyk, R., Wait, I., Walker, A. L., Wallace, B., Welz, M., Williams, L. P., Xaia, B., Young, N., and Zitha, S.
Abstract: New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100x larger than during its dormant state. The X-ray flux one month after reactivation was at least 800x larger than during quiescence, and has been decaying exponentially on a 111+/-19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation., Comment: Published in ApJ (2018 April 5); 13 pages, 4 figures
Published: 2018
Full Text: View/download PDF

24. Documentation and identification of substitute decision-makers/persons responsible in residential aged care facilities in Victoria.

Author: Gee W., Workman B., Morton J., Welz M., Gee W., Workman B., Morton J., and Welz M.
Published: 2016

25. Engineering and Science Highlights of the KAT-7 Radio Telescope

Author: Foley, A. R., Alberts, T., Armstrong, R P., Barta, A., Bauermeister, E. F., Bester, H., Blose, S., Booth, R. S., Botha, D. H., Buchner, S. J., Carignan, C., Cheetham, T., Cloete, K., Coreejes, G., Crida, R. C., Cross, S. D., Curtolo, F., Dikgale, A., de Villiers, M. S., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B., Fender, R. P., Fijalkowski, M., Fourie, D., Frank, B., George, D., Gibbs, P., Goedhart, S., Grobbelaar, J., Gumede, S. C., Herselman, P., Hess, K. M., Hoek, N., Horrell, J., Jonas, J. L., Jordaan, J. D. B., Julie, R., Kapp, F., Kotzé, P., Kusel, T., Langman, A., Lehmensiek, R., Liebenberg, D., Liebenberg, I. J. V., Loots, A., Lord, R. T., Lucero, D. M., Ludick, J., Macfarlane, P., Madlavana, M., Magnus, L., Magozore, C., Malan, J. A., Manley, J. R., Marais, L., Marais, N., Marais, S. J., Maree, M., Martens, A., Mokone, O., Moss, V., Mthembu, S., New, W., Nicholson, G. D., van Niekerk, P. C., Oozeer, N., Passmoor, S. S., Peens-Hough, A., Pińska, A. B., Prozesky, P., Rajan, S., Ratcliffe, S., Renil, R., Richter, L. L., Rosekrans, D., Rust, A., Schröder, A. C., Schwardt, L. C., Seranyane, S., Serylak, M., Shepherd, D. S., Siebrits, R., Sofeya, L., Spann, R., Springbok, R., Swart, P. S., Thondikulam, Venkatasubramani L., Theron, I. P., Tiplady, A., Toruvanda, O., Tshongweni, S., Heever, L. van den, van der Merwe, C., van Rooyen, R., Wakhaba, S., Walker, A. L., Welz, M., Williams, L., Wolleben, M., Woudt, P. A., Young, N. J., Zwart, J. T. L., Foley, A. R., Alberts, T., Armstrong, R P., Barta, A., Bauermeister, E. F., Bester, H., Blose, S., Booth, R. S., Botha, D. H., Buchner, S. J., Carignan, C., Cheetham, T., Cloete, K., Coreejes, G., Crida, R. C., Cross, S. D., Curtolo, F., Dikgale, A., de Villiers, M. S., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B., Fender, R. P., Fijalkowski, M., Fourie, D., Frank, B., George, D., Gibbs, P., Goedhart, S., Grobbelaar, J., Gumede, S. C., Herselman, P., Hess, K. M., Hoek, N., Horrell, J., Jonas, J. L., Jordaan, J. D. B., Julie, R., Kapp, F., Kotzé, P., Kusel, T., Langman, A., Lehmensiek, R., Liebenberg, D., Liebenberg, I. J. V., Loots, A., Lord, R. T., Lucero, D. M., Ludick, J., Macfarlane, P., Madlavana, M., Magnus, L., Magozore, C., Malan, J. A., Manley, J. R., Marais, L., Marais, N., Marais, S. J., Maree, M., Martens, A., Mokone, O., Moss, V., Mthembu, S., New, W., Nicholson, G. D., van Niekerk, P. C., Oozeer, N., Passmoor, S. S., Peens-Hough, A., Pińska, A. B., Prozesky, P., Rajan, S., Ratcliffe, S., Renil, R., Richter, L. L., Rosekrans, D., Rust, A., Schröder, A. C., Schwardt, L. C., Seranyane, S., Serylak, M., Shepherd, D. S., Siebrits, R., Sofeya, L., Spann, R., Springbok, R., Swart, P. S., Thondikulam, Venkatasubramani L., Theron, I. P., Tiplady, A., Toruvanda, O., Tshongweni, S., Heever, L. van den, van der Merwe, C., van Rooyen, R., Wakhaba, S., Walker, A. L., Welz, M., Williams, L., Wolleben, M., Woudt, P. A., Young, N. J., and Zwart, J. T. L.
Abstract: The construction of the KAT-7 array in the Karoo region of the Northern Cape in South Africa was intended primarily as an engineering prototype for technologies and techniques applicable to the MeerKAT telescope. This paper looks at the main engineering and scien- tific highlights from this effort, and discusses their applicability to both MeerKAT and other next-generation radio telescopes. In particular we found that the composite dish surface works well, but it becomes complicated to fabricate for a dish lacking circular symmetry; the Stir- ling cycle cryogenic system with ion pump to achieve vacuum works but demands much higher maintenance than an equivalent Gifford-McMahon cycle system; the ROACH (Recon- figurable Open Architecture Computing Hardware)-based correlator with SPEAD (Stream- ing Protocol for Exchanging Astronomical Data) protocol data transfer works very well and KATCP (Karoo Array Telescope Control Protocol) control protocol has proven very flexible and convenient. KAT-7 has also been used for scientific observations where it has a niche in mapping low surface-brightness continuum sources, some extended HI halos and OH masers in star-forming regions. It can also be used to monitor continuum source variability, observe pulsars, and make VLBI observations
Published: 2016
Full Text: View/download PDF

26. Documentation and identification of substitute decision-makers/persons responsible in residential aged care facilities in Victoria.

Author: Gee W., Workman B., Morton J., Welz M., Gee W., Workman B., Morton J., and Welz M.
Published: 2016

27. Engineering and Science Highlights of the KAT-7 Radio Telescope

Author: Foley, A. R., Alberts, T., Armstrong, R P., Barta, A., Bauermeister, E. F., Bester, H., Blose, S., Booth, R. S., Botha, D. H., Buchner, S. J., Carignan, C., Cheetham, T., Cloete, K., Coreejes, G., Crida, R. C., Cross, S. D., Curtolo, F., Dikgale, A., de Villiers, M. S., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B., Fender, R. P., Fijalkowski, M., Fourie, D., Frank, B., George, D., Gibbs, P., Goedhart, S., Grobbelaar, J., Gumede, S. C., Herselman, P., Hess, K. M., Hoek, N., Horrell, J., Jonas, J. L., Jordaan, J. D. B., Julie, R., Kapp, F., Kotzé, P., Kusel, T., Langman, A., Lehmensiek, R., Liebenberg, D., Liebenberg, I. J. V., Loots, A., Lord, R. T., Lucero, D. M., Ludick, J., Macfarlane, P., Madlavana, M., Magnus, L., Magozore, C., Malan, J. A., Manley, J. R., Marais, L., Marais, N., Marais, S. J., Maree, M., Martens, A., Mokone, O., Moss, V., Mthembu, S., New, W., Nicholson, G. D., van Niekerk, P. C., Oozeer, N., Passmoor, S. S., Peens-Hough, A., Pińska, A. B., Prozesky, P., Rajan, S., Ratcliffe, S., Renil, R., Richter, L. L., Rosekrans, D., Rust, A., Schröder, A. C., Schwardt, L. C., Seranyane, S., Serylak, M., Shepherd, D. S., Siebrits, R., Sofeya, L., Spann, R., Springbok, R., Swart, P. S., Thondikulam, Venkatasubramani L., Theron, I. P., Tiplady, A., Toruvanda, O., Tshongweni, S., Heever, L. van den, van der Merwe, C., van Rooyen, R., Wakhaba, S., Walker, A. L., Welz, M., Williams, L., Wolleben, M., Woudt, P. A., Young, N. J., Zwart, J. T. L., Foley, A. R., Alberts, T., Armstrong, R P., Barta, A., Bauermeister, E. F., Bester, H., Blose, S., Booth, R. S., Botha, D. H., Buchner, S. J., Carignan, C., Cheetham, T., Cloete, K., Coreejes, G., Crida, R. C., Cross, S. D., Curtolo, F., Dikgale, A., de Villiers, M. S., Toit, L. J. du, Esterhuyse, S. W. P., Fanaroff, B., Fender, R. P., Fijalkowski, M., Fourie, D., Frank, B., George, D., Gibbs, P., Goedhart, S., Grobbelaar, J., Gumede, S. C., Herselman, P., Hess, K. M., Hoek, N., Horrell, J., Jonas, J. L., Jordaan, J. D. B., Julie, R., Kapp, F., Kotzé, P., Kusel, T., Langman, A., Lehmensiek, R., Liebenberg, D., Liebenberg, I. J. V., Loots, A., Lord, R. T., Lucero, D. M., Ludick, J., Macfarlane, P., Madlavana, M., Magnus, L., Magozore, C., Malan, J. A., Manley, J. R., Marais, L., Marais, N., Marais, S. J., Maree, M., Martens, A., Mokone, O., Moss, V., Mthembu, S., New, W., Nicholson, G. D., van Niekerk, P. C., Oozeer, N., Passmoor, S. S., Peens-Hough, A., Pińska, A. B., Prozesky, P., Rajan, S., Ratcliffe, S., Renil, R., Richter, L. L., Rosekrans, D., Rust, A., Schröder, A. C., Schwardt, L. C., Seranyane, S., Serylak, M., Shepherd, D. S., Siebrits, R., Sofeya, L., Spann, R., Springbok, R., Swart, P. S., Thondikulam, Venkatasubramani L., Theron, I. P., Tiplady, A., Toruvanda, O., Tshongweni, S., Heever, L. van den, van der Merwe, C., van Rooyen, R., Wakhaba, S., Walker, A. L., Welz, M., Williams, L., Wolleben, M., Woudt, P. A., Young, N. J., and Zwart, J. T. L.
Abstract: The construction of the KAT-7 array in the Karoo region of the Northern Cape in South Africa was intended primarily as an engineering prototype for technologies and techniques applicable to the MeerKAT telescope. This paper looks at the main engineering and scien- tific highlights from this effort, and discusses their applicability to both MeerKAT and other next-generation radio telescopes. In particular we found that the composite dish surface works well, but it becomes complicated to fabricate for a dish lacking circular symmetry; the Stir- ling cycle cryogenic system with ion pump to achieve vacuum works but demands much higher maintenance than an equivalent Gifford-McMahon cycle system; the ROACH (Recon- figurable Open Architecture Computing Hardware)-based correlator with SPEAD (Stream- ing Protocol for Exchanging Astronomical Data) protocol data transfer works very well and KATCP (Karoo Array Telescope Control Protocol) control protocol has proven very flexible and convenient. KAT-7 has also been used for scientific observations where it has a niche in mapping low surface-brightness continuum sources, some extended HI halos and OH masers in star-forming regions. It can also be used to monitor continuum source variability, observe pulsars, and make VLBI observations
Published: 2016
Full Text: View/download PDF

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1. The SARAO MeerKAT 1.3 GHz Galactic Plane Survey

2. The 1.28 GHz MeerKAT Galactic Center Mosaic

3. The 1.28 GHz MeerKAT Galactic Center Mosaic

4. The MeerKAT Telescope as a Pulsar Facility: System verification and early science results from MeerTime

5. The MeerKAT Galaxy Cluster Legacy Survey I. Survey Overview and Highlights

6. The MeerKAT Galaxy Cluster Legacy Survey I. Survey Overview and Highlights

7. The MeerKAT Telescope as a Pulsar Facility: System verification and early science results from MeerTime

8. Does More Expert Adjustment Associate with Less Accurate Professional Forecasts?

9. The Cash Use of the Malaysian Ringgit: Can it Be More Efficient?

10. The MeerKAT Telescope as a Pulsar Facility: System verification and early science results from MeerTime

11. Does More Expert Adjustment Associate with Less Accurate Professional Forecasts?

12. Cash Use of the Taiwan Dollar

13. Cash Use of the Taiwan Dollar

14. The 1.28 GHz MeerKAT DEEP2 Image

15. Inflation of 430-parsec bipolar radio bubbles in the Galactic Centre by an energetic event

16. Cash use of the Taiwan dollar: Is it efficient?

17. The 1.28 GHz MeerKAT DEEP2 Image

18. Inflation of 430-parsec bipolar radio bubbles in the Galactic Centre by an energetic event

19. Cash use of the Taiwan dollar. Is it efficient

20. Cash use of the Taiwan dollar: Is it efficient?

21. Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

22. Perforin inhibition protects from lethal endothelial damage during fulminant viral hepatitis

23. Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

24. Documentation and identification of substitute decision-makers/persons responsible in residential aged care facilities in Victoria.

25. Engineering and Science Highlights of the KAT-7 Radio Telescope

26. Documentation and identification of substitute decision-makers/persons responsible in residential aged care facilities in Victoria.

27. Engineering and Science Highlights of the KAT-7 Radio Telescope

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