Search Results - "Low-Frequency Array"

LOFAR: The LOw-Frequency ARray by van Haarlem, M., Wise, M., Gunst, A., Miller-Jones, James

“…LOFAR, the LOw-Frequency ARray, is a new-generation radio interferometer constructed in the north of the Netherlands and across Europe. …”
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A low frequency array of simple radio telescopes for the detection of solar x-ray and radio flares and the study of the Ionosphere by Lord, Christopher John

“…The thesis: “A low frequency array of simple radio telescopes for the detection of solar X-ray and radio flares, and the study of the ionosphere”, describes the development of antennas, receivers and software for a radio telescope system that captures data from the 16 MHz to 30MHz radio spectrum to a personal computer. …”
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Interstellar and intergalactic scattering as astrophysical probes by Koay, Jun Yi

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The Murchison Widefield Array: solar science with the low frequency SKA Precursor by Tingay, Steven, Oberoi, D., Cairns, I., Donea, A., Duffin, R., Arcus, Wayne, Bernardi, G., Bowman, J., Briggs, F., Bunton, J., Cappallo, R., Corey, B., Deshpande, A., deSouza, L., Emrich, David, Gaensler, B., Goeke, R., Greenhill, L., Hazelton, B., Herne, David, Hewitt, J., Johnston-Hollitt, M., Kaplan, D., Kasper, J., Kennewell, J., Kincaid, B., Koenig, R., Kratzenberg, E., Lonsdale, C., Lynch, Mervyn, McWhirter, S., Mitchell, D., Morales, M., Morgan, E., Ord, S., Pathikulangara, J., Prabu, T., Remillard, R., Rogers, A., Roshi, A., Salah, J., Udaya-Shankar, N., Srivani, K., Stevens, J., Subrahmanyan, R., Waterson, Mark, Wayth, Randall, Webster, R., Whitney, A., Williams, A., Williams, C., Wyithe, J.

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Reconsidering the advantages of the three-dimensional representation of the interferometric transform for imaging with non-coplanar baselines and wide fields of view by Smith, D., Young, A., Davidson, David

“…Radio telescopes with baselines that span thousands of kilometres and with fields of view that span tens of degrees have been recently deployed, such as the Low Frequency Array, and are currently being developed, such as the Square Kilometre Array. …”
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The effect of the ionosphere on astronomical observations below 100 MHz by De Gasperin, F., Mevius, M., Intema, Hubertus

“…We compare our predictions with data from the Low Frequency Array (LOFAR). We show that the systematic errors on the phases of the instrument can be described as a sum of four effects (clock, ionosphere 1st, 2nd, and 3rd order). …”
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Revisiting Hybrid Interferometry With Low-Frequency Radio Astronomy Arrays by Sutinjo, Adrian, Ung, D., Colegate, T., Wayth, R., Hall, Peter, Acedo, E.

“…We encounter this in the characterization of low-frequency antenna/array prototypes using a homogenous low-frequency array telescope such as the Murchison Widefield Array (MWA). …”
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The Low-Frequency Environment of the Murchison Widefield Array: Radio-Frequency Interference Analysis and Mitigation by Offringa, A., Wayth, Randall, Hurley-Walker, N., Kaplan, D., Barry, N., Beardsley, A., Bell, M., Bernardi, G., Bowman, J., Briggs, F., Callingham, J., Cappallo, R., Carroll, P., Deshpande, A., Dillon, J., Dwarakanath, K., Ewall-Wice, A., Feng, L., For, B., Gaensler, B., Greenhill, L., Hancock, P., Hazelton, B., Hewitt, J., Hindson, L., Jacobs, D., Johnston-Hollitt, M., Kapinska, A., Kim, H., Kittiwisit, P., Lenc, E., Line, J., Loeb, A., Lonsdale, C., McKinley, B., McWhirter, S., Mitchell, D., Morales, M., Morgan, E., Morgan, J., Neben, A., Oberoi, D., Ord, Stephen, Paul, S., Pindor, B., Pober, J., Prabu, T., Procopio, P., Riding, J., Shankar, N., Sethi, S., Srivani, K., Staveley-Smith, L., Subrahmanyan, R., Sullivan, I., Tegmark, M., Thyagarajan, N., Tingay, Steven, Trott, C., Webster, R., Williams, A., Williams, C., Wu, C., Wyithe, J., Zheng, Q.

“…The results are compared to a previously published Low-Frequency Array radio-frequency interference survey. …”
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Closed-form Jones matrix of dual-polarized inverted-vee dipole antennas over lossy ground by Baelemans, R., Sutinjo, Adrian, Hall, Peter, Smolders, A., Arts, M., De Lera Acedo, E.

“…This result is used to explain the polarization properties of the Square Kilometre Array Log-periodic Antenna. Through the LOw-Frequency ARray Low-Band Antenna (LOFAR-LBA), the importance of the size of the ground plane is explained. …”
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Pipeline Collector: Gathering performance data for distributed astronomical pipelines by Mechev, A., Plaat, A., Oonk, J., Intema, Hubertus, Röttgering, H.

“…In this work we have developed such a utility and integrated it with the calibration pipeline of the Low Frequency Array, LOFAR, a leading radio telescope. We tested the tool by running the pipeline on several different compute platforms and collected the performance data. …”
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Using low-frequency pulsar observations to study the 3-D structure of the Galactic magnetic field by Sobey, Charlotte, LOFAR Collaborators, MWA Collaborators

“…This is demonstrated by a catalogue of RMs (corrected for ionospheric Faraday rotation) from the Low Frequency Array (LOFAR), with a growing complementary catalogue in the southern hemisphere from the Murchison Widefield Array (MWA). …”
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Computationally Efficient Radio Frequency Source Localization for Radio Interferometric Arrays by Steeb, J., Davidson, David, Wijnholds, S.

“…The accuracy of the algorithm is validated using data generated by low-frequency array while a hexacopter was flying around it and broadcasting a continuous-wave signal. …”
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Gentle reenergization of electrons in merging galaxy clusters by De Gasperin, F., Intema, Hubertus, Shimwell, T., Brunetti, G., Brüggen, M., Enßlin, T., Van Weeren, R., Bonafede, A., Röttgering, H.

“…Although the hot thermal gas that pervades galaxy clusters is relatively well understood through observations with x-ray satellites, our understanding of the nonthermal part of the intracluster medium (ICM) remains incomplete. With Low-Frequency Array (LOFAR) and Giant Metrewave Radio Telescope (GMRT) observations, we have identified a phenomenon that can be unveiled only at extremely low radio frequencies and offers new insights into the nonthermal component. …”
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An Automated Scalable Framework for Distributing Radio Astronomy Processing Across Clusters and Clouds by Mechev, A., Oonk, J., Danezi, A., Shimwell, T., Schrijvers, C., Intema, Hubertus, Plaat, A., Rttgering, H.

“…The Low Frequency Array (LOFAR) radio telescope is an international aperture synthesis radio telescope used to study the Universe at low frequencies. …”
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Interplanetary Scintillation with the Murchison Widefield Array V: An all-sky survey of compact sources using a modern low-frequency radio telescope by Morgan, John, Macquart, Jean-Pierre, Chhetri, Rajan, Ekers, Ronald, Tingay, Steven, Sadler, E.

“…While this survey gives important complementary information to low-resolution survey, providing information on the sub-arsecond structure of every source, a survey of this kind has not been attempted in the era of low-frequency imaging arrays such as the Murchison Widefield Array and LOw Frequency Array. Here we set out the capabilities of such a survey, describing the limitations imposed by the heliocentric observing geometry and by the instrument itself. …”
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The effect of the ionosphere on ultra-low-frequency radio-interferometric observations by De Gasperin, F., Mevius, M., Rafferty, D., Intema, Hubertus, Fallows, R.

“…We also provide guidelines for observations and data reduction at these frequencies with the LOw Frequency ARray (LOFAR) and future instruments such as the Square Kilometre Array (SKA). …”
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Lofar Facet Calibration by Weeren, R., Williams, W., Hardcastle, M., Shimwell, T., Rafferty, D., Sabater, J., Heald, G., Sridhar, S., Dijkema, T., Brunetti, G., Brüggen, M., Andrade-Santos, F., Ogrean, G., Röttgering, H., Dawson, W., Forman, W., Gasperin, F., Jones, C., Miley, G., Rudnick, L., Sarazin, C., Bonafede, A., Best, P., Birzan, L., Cassano, R., Chyzy, K., Croston, J., Ensslin, T., Ferrari, C., Hoeft, M., Horellou, C., Jarvis, M., Kraft, R., Mevius, M., Intema, Hubertus, Murray, S., Orrú, E., Pizzo, R., Simionescu, A., Stroe, A., Tol, S., White, G.

“…LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. …”
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An Ultra-High Time Resolution Cosmic-Ray Detection Mode for the Murchison Widefield Array by Williamson, A., James, Clancy, Tingay, Steven, McSweeney, Sam, Ord, S.M.

“…The radio-wavelength detection of extensive air showers (EASs) initiated by cosmic-ray interactions in the Earth's atmosphere is a promising technique for investigating the origin of these particles and the physics of their interactions. The Low-frequency Array (LOFAR) and the Owens Valley Long Wavelength Array (OVRO-LWA) have both demonstrated that the dense cores of low-frequency radio telescope arrays yield detailed information on the radiation ground pattern, which can be used to reconstruct key EAS properties and infer the primary cosmic-ray composition. …”
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Detailed Radio View on Two Stellar Explosions and Their Host Galaxy: XRF 080109/SN 2008D and SN 2007uy in NGC 2770 by van der Horst, A., Kamble, A., Paragi, Z., Sage, L., Pal, S., Taylor, G., Kouveliotou, C., Granot, J., Ramirez-Ruiz, E., Ishwara-Chandra, C., Oosterloo, T., Wijers, R., Wiersema, K., Strom, R., Bhattacharya, D., Rol, E., Starling, R., Curran, Peter, Garrett, M.

“…Furthermore, we discuss the near-future observing possibilities of the two SNe andtheir host galaxy at low radio frequencies with the Low Frequency Array.…”
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A plethora of diffuse steep spectrum radio sources in Abell 2034 revealed by LOFAR by Shimwell, T., Luckin, J., Brüggen, M., Brunetti, G., Intema, Hubertus, Owers, M., Röttgering, H., Stroe, A., Van Weeren, R., Williams, W., Cassano, R., De Gasperin, F., Hoang, D., Hardcastle, M., Sridhar, S., Sabater, J., Best, P., Bonafede, A., Chyzy, K., Enßlin, T., Ferrari, C., Haverkorn, M., Hoeft, M., Horellou, C., McKean, J., Morabito, L., Orrù, E., Pizzo, R., Retana-Montenegro, E., White, G.

“…With Low-Frequency Array (LOFAR) observations, we have discovered a diverse assembly of steep spectrum emission that is apparently associated with the intracluster medium (ICM) of the merging galaxy cluster Abell 2034. …”
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