Search Results - "Offringa, André R."

Interpreting LOFAR 21-cm signal upper limits at z ≈ 9.1 in the context of high-z galaxy and reionization observations by Greig, Bradley, Mesinger, Andrei, Koopmans, Léon V E, Ciardi, Benedetta, Mellema, Garrelt, Zaroubi, Saleem, Giri, Sambit K, Ghara, Raghunath, Ghosh, Abhik, Iliev, Ilian T, Mertens, Florent G, Mondal, Rajesh, Offringa, André R, Pandey, Vishambhar N

“…ABSTRACT Using the latest upper limits on the 21-cm power spectrum at z ≈ 9.1 from the Low Frequency Array (LOFAR), we explore the regions of parameter space…”
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RFI flagging in solar and space weather low frequency radio observations by Zhang, Peijin, Offringa, André R, Zucca, Pietro, Kozarev, Kamen, Mancini, Mattia

“…ABSTRACT Radio spectroscopy provides a unique inspection perspective for solar and space weather research, which can reveal the plasma and energetic electron…”
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Real-time imaging of density ducts between the plasmasphere and ionosphere by Loi, Shyeh Tjing, Murphy, Tara, Cairns, Iver H., Menk, Frederick W., Waters, Colin L., Erickson, Philip J., Trott, Cathryn M., Hurley-Walker, Natasha, Morgan, John, Lenc, Emil, Offringa, André R., Bell, Martin E., Ekers, Ronald D., Gaensler, B. M., Lonsdale, Colin J., Feng, Lu, Hancock, Paul J., Kaplan, David L., Bernardi, G., Bowman, J. D., Briggs, F., Cappallo, R. J., Deshpande, A. A., Greenhill, L. J., Hazelton, B. J., Johnston-Hollitt, M., McWhirter, S. R., Mitchell, D. A., Morales, M. F., Morgan, E., Oberoi, D., Ord, S. M., Prabu, T., Shankar, N. Udaya, Srivani, K. S., Subrahmanyan, R., Tingay, S. J., Wayth, R. B., Webster, R. L., Williams, A., Williams, C. L.

“…Ionization of the Earth's atmosphere by sunlight forms a complex, multilayered plasma environment within the Earth's magnetosphere, the innermost layers being…”
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Limits on low-frequency radio emission from southern exoplanets with the Murchison Widefield Array by Murphy, Tara, Bell, Martin E, Kaplan, David L, Gaensler, B M, Offringa, Andre R, Lenc, Emil, Hurley-Walker, Natasha, Bernardi, G, Bowman, J D, Briggs, F, Cappallo, R J, Corey, B E, Deshpande, A A, Emrich, D, Goeke, R, Greenhill, L J, Hazelton, B J, Hewitt, J N, Johnston-Hollitt, M, Kasper, J C, Kratzenberg, E, Lonsdale, C J, Lynch, M J, McWhirter, S R, Mitchell, D A, Morales, M F, Morgan, E, Oberoi, D, Ord, S M, Prabu, T, Rogers, A E E, Roshi, D A, Shankar, N Udaya, Srivani, K S, Subrahmanyan, R, Tingay, S J, Waterson, M, Wayth, R B, Webster, R L, Whitney, A R, Williams, A, Williams, C L

“…We present the results of a survey for low-frequency radio emission from 17 known exoplanetary systems with the Murchison Widefield Array. This sample includes…”
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Quantifying ionospheric effects on time-domain astrophysics with the Murchison Widefield Array by Loi, Shyeh Tjing, Murphy, Tara, Bell, Martin E., Kaplan, David L., Lenc, Emil, Offringa, André R., Hurley-Walker, Natasha, Bernardi, G., Bowman, J. D., Briggs, F., Cappallo, R. J., Corey, B. E., Deshpande, A. A., Emrich, D., Gaensler, B. M., Goeke, R., Greenhill, L. J., Hazelton, B. J., Johnston-Hollitt, M., Kasper, J. C., Kratzenberg, E., Lonsdale, C. J., Lynch, M. J., McWhirter, S. R., Mitchell, D. A., Morales, M. F., Morgan, E., Oberoi, D., Ord, S. M., Prabu, T., Rogers, A. E. E., Roshi, A., Shankar, N. Udaya, Srivani, K. S., Subrahmanyan, R., Tingay, S. J., Waterson, M., Wayth, R. B., Webster, R. L., Whitney, A. R., Williams, A., Williams, C. L.

“…Refraction and diffraction of incoming radio waves by the ionosphere induce time variability in the angular positions, peak amplitudes and shapes of radio…”
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LOFAR: Recent Imaging Results and Future Prospects by Heald, George, Bell, Michael R., Horneffer, Andreas, Offringa, André R., Pizzo, Roberto, van der Tol, Sebastiaan, van Weeren, Reinout J., van Zwieten, Joris E., Anderson, James M., Beck, Rainer, van Bemmel, Ilse, Bîrzan, Laura, Bonafede, Annalisa, Conway, John, Ferrari, Chiara, De Gasperin, Francesco, Haverkorn, Marijke, Jackson, Neal, Macario, Giulia, McKean, John, Miraghaei, Halime, Orrù, Emanuela, Rafferty, David, Röttgering, Huub, Scaife, Anna, Shulevski, Aleksandar, Sotomayor, Carlos, Tasse, Cyril, Trasatti, Monica, Wucknitz, Olaf

“…The Low-Frequency Array (LOFAR) is under construction in the Netherlands and in several surrounding European countries. In this contribution, we describe the…”
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Efficient and Robust Path Openings Using the Scale-Invariant Rank Operator by van de Gronde, Jasper J., Offringa, André R., Roerdink, Jos B. T. M.

“…Some basic properties of a slightly generalized version of the scale-invariant rank operator are given, and it is shown how this operator can be used to create…”
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Reionization and the Cosmic Dawn with the Square Kilometre Array by Mellema, Garrelt, Koopmans, Léon V. E., Abdalla, Filipe A., Bernardi, Gianni, Ciardi, Benedetta, Daiboo, Soobash, de Bruyn, A. G., Datta, Kanan K., Falcke, Heino, Ferrara, Andrea, Iliev, Ilian T., Iocco, Fabio, Jelić, Vibor, Jensen, Hannes, Joseph, Ronniy, Labroupoulos, Panos, Meiksin, Avery, Mesinger, Andrei, Offringa, André R., Pandey, V. N., Pritchard, Jonathan R., Santos, Mario G., Schwarz, Dominik J., Semelin, Benoit, Vedantham, Harish, Yatawatta, Sarod, Zaroubi, Saleem

“…The Square Kilometre Array (SKA) will have a low frequency component (SKA-low) which has as one of its main science goals the study of the redshifted 21 cm…”
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Constraining the epoch of reionization with the variance statistic: simulations of the LOFAR case by Patil, Ajinkya H., Zaroubi, Saleem, Chapman, Emma, Jelić, Vibor, Harker, Geraint, Abdalla, Filipe B., Asad, Khan M. B., Bernardi, Gianni, Brentjens, Michiel A., de Bruyn, A. G., Bus, Sander, Ciardi, Benedetta, Daiboo, Soobash, Fernandez, Elizabeth R., Ghosh, Abhik, Jensen, Hannes, Kazemi, Sanaz, Koopmans, Léon V. E., Labropoulos, Panagiotis, Mevius, Maaijke, Martinez, Oscar, Mellema, Garrelt, Offringa, Andre R., Pandey, Vishhambhar N., Schaye, Joop, Thomas, Rajat M., Vedantham, Harish K., Veligatla, Vamsikrishna, Wijnholds, Stefan J., Yatawatta, Sarod

“…Several experiments are underway to detect the cosmic-redshifted 21-cm signal from neutral hydrogen from the Epoch of Reionization (EoR). Due to their very low…”
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Development of Python-based pipelines for LOFAR2.0 and SKA by Wijnholds, Stefan J., Dijkema, Tammo Jan, Groot, Herman, Lukkezen, Maikel, Nijhuis, Maik, Offringa, Andre R., Salvoni, Chiara, Slusarenko, Nicolas, Tol, Sebastiaan van der

“…The data production rate of future telescopes like LOFAR2.0 and SKA will require processing pipelines with high computational performace and a large degree of…”
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Efficient Deconvolution of a Heterogeneous Array Observation Using a Direction-Dependent Point Spread Function by Wijnholds, Stefan J., Dijkema, Tammo Jan, Groot, Herman, Lukkezen, Maikel, Nijhuis, Maik, Offringa, Andre R., Salvoni, Chiara, Van Der Tol, Sebastiaan, De Wever, Mark

“…For large aperture arrays like LOFAR and SKA-LOW, the point spread function (PSF) varies significantly across the wide field-of-view (FoV) of these…”
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RFI Flagging in Solar and Space Weather Low Frequency Radio Observations by Zhang, Peijin, Offringa, André R, Zucca, Pietro, Kozarev, Kamen, Mancini, Mattia

“…Radio spectroscopy provides a unique inspection perspective for solar and space weather research, which can reveal the plasma and energetic electron…”
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Image Domain Gridding: a fast method for convolutional resampling of visibilities by van der Tol, Sebastiaan, Veenboer, Bram, Offringa, André R

“…A&A 616 A27 (2018) In radio astronomy obtaining a high dynamic range in synthesis imaging of wide fields requires a correction for time and direction-dependent…”
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Interpreting LOFAR 21-cm signal upper limits at z~9.1 in the context of high-z galaxy and reionisation observations by Greig, Bradley, Mesinger, Andrei, Koopmans, Léon V. E, Ciardi, Benedetta, Mellema, Garrelt, Zaroubi, Saleem, Giri, Sambit K, Ghara, Raghunath, Ghosh, Abhik, Iliev, Ilian T, Mertens, Florent G, Mondal, Rajesh, Offringa, André R, Pandey, Vishambhar N

“…Using the latest upper limits on the 21-cm power spectrum at $z\approx9.1$ from the Low Frequency Array (LOFAR), we explore regions of parameter space which…”
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Constraining the epoch of reionization with the variance statistic: simulations of the LOFAR case by Patil, Ajinkya H, Zaroubi, Saleem, Chapman, Emma, Jelić, Vibor, Harker, Geraint, Abdalla, Filipe B, Asad, Khan M. B, Bernardi, Gianni, Brentjens, Michiel A, de Bruyn, A. G, Bus, Sander, Ciardi, Benedetta, Daiboo, Soobash, Fernandez, Elizabeth R, Ghosh, Abhik, Jensen, Hannes, Kazemi, Sanaz, Koopmans, Léon V. E, Labropoulos, Panagiotis, Mevius, Maaijke, Martinez, Oscar, Mellema, Garrelt, Offringa, Andre. R, Pandey, Vishhambhar N, Schaye, Joop, Thomas, Rajat M, Vedantham, Harish K, Veligatla, Vamsikrishna, Wijnholds, Stefan J, Yatawatta, Sarod

“…MNRAS 443 1113 (2014) Several experiments are underway to detect the cosmic redshifted 21-cm signal from neutral hydrogen from the Epoch of Reionization (EoR)…”
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Searching for Dark Matter Signals from Local Dwarf Spheroidal Galaxies at Low Radio Frequencies in the GLEAM Survey by Cook, Robin H. W, Seymour, Nick, Spekkens, Kristine, Hurley-Walker, Natasha, Hancock, Paul J, Bell, Martin E, Callingham, Joseph R, For, Bi-Qing, Franzen, Thomas M. O, Gaensler, Bryan M, Hindson, Luke, Jackson, Carole A, Johnston-Hollitt, Melanie, Kapińska, Anna D, Morgan, John, Offringa, André R, Procopio, Pietro, Staveley-Smith, Lister, Wayth, Randall B, Wu, Chen, Zheng, Qian

“…The search for emission from weakly interacting massive particle (WIMP) dark matter annihilation and decay has become a multi-pronged area of research not only…”
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Waves in the sky: Probing the ionosphere with the Murchison Widefield Array by Shyeh Tjing Loi, Murphy, Tara, Cairns, Iver H., Trott, Cathryn M., Bell, Martin E., Hurley-Walker, Natasha, Morgan, John, Lenc, Emil, Offringa, Andre R., Menk, Frederick W., Waters, Colin L., Lu Feng, Hancock, Paul J., Kaplan, David L., Kudryavtseva, Nadia, Lonsdale, Colin J., Erickson, Philip, Coster, Anthea, Ekers, Ronald D., Bernardi, G., Bowman, J. D., Briggs, F., Cappallo, R. J., Deshpande, A. A., Gaensler, B. M., Greenhill, L. J., Hazelton, B. J., Johnston-Hollitt, M., McWhirter, S. R., Mitchell, D. A., Morales, M. F., Morgan, E., Oberoi, D., Ord, S. M., Prabu, T., Shankar, N. Udaya, Srivani, K. S., Subrahmanyan, R., Tingay, S. J., Wayth, R. B., Webster, R. L., Williams, A., Williams, C. L.

“…Summary form only given. Low-frequency, wide-field radio telescopes such as the Murchison Widefield Array (MWA) enable the dense spatial sampling of the…”
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LOFAR: Recent imaging results & future prospects by Heald, George, Bell, Michael R, Horneffer, Andreas, Offringa, André R, Pizzo, Roberto, van der Tol, Sebastiaan, van Weeren, Reinout J, van Zwieten, Joris E, Anderson, James M, Beck, Rainer, van Bemmel, Ilse, Bîrzan, Laura, Bonafede, Annalisa, Conway, John, Ferrari, Chiara, De Gasperin, Francesco, Haverkorn, Marijke, Jackson, Neal, Macario, Giulia, McKean, John, Miraghaei, Halime, Orrù, Emanuela, Rafferty, David, Röttgering, Huub, Scaife, Anna, Shulevski, Aleksandar, Sotomayor, Carlos, Tasse, Cyril, Trasatti, Monica, Wucknitz, Olaf

“…The Low Frequency Array (LOFAR) is under construction in the Netherlands and in several surrounding European countries. In this contribution, we describe the…”
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Candidate radio supernova remnants observed by the GLEAM survey over $345^\circ < l < 60^\circ$ and $180^\circ < l < 240^\circ by Hurley-Walker, Natasha, Gaensler, Bryan M, Leahy, Denis A, Filipovic, Miroslav D, Hancock, Paul J, Franzen, Thomas M. O, Offringa, Andre R, Callingham, Joseph R, Hindson, Luke, Wu, Chen, Bell, Martin E, For, Bi-Qing, Johnston-Hollitt, Melanie, Kapinska, Anna D, Morgan, John, Murphy, Tara, McKinley, Benjamin, Procopio, Pietro, Staveley-Smith, Lister, Wayth, Randall B, Zheng, Cathie Q

“…We examined the latest data release from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey covering $345^\circ < l < 60^\circ$,…”
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New candidate radio supernova remnants detected in the GLEAM survey over $345^\circ < l < 60^\circ$, $180^\circ < l < 240^\circ by Hurley-Walker, Natasha, Filipovic, Miroslav D, Gaensler, Bryan M, Leahy, Denis A, Hancock, Paul J, Franzen, Thomas M. O, Offringa, Andre R, Callingham, Joseph R, Hindson, Luke, Wu, Chen, Bell, Martin E, For, Bi-Qing, Johnston-Hollitt, Melanie, Kapinska, Anna D, Morgan, John, Murphy, Tara, McKinley, Benjamin, Procopio, Pietro, Staveley-Smith, Lister, Wayth, Randall B, Zheng, Cathie Q

“…We have detected 27 new supernova remnants (SNRs) using a new data release of the GLEAM survey from the Murchison Widefield Array (MWA) telescope, including…”
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