Search Results - "Offringa, A.R."

The AARTFAAC Cosmic Explorer: observations of the 21-cm power spectrum in the EDGES absorption trough by Gehlot, B K, Mertens, F G, Koopmans, L V E, Offringa, A R, Shulevski, A, Mevius, M, Brentjens, M A, Kuiack, M, Pandey, V N, Rowlinson, A, Sardarabadi, A M, Vedantham, H K, Wijers, R A M J, Yatawatta, S, Zaroubi, S

“…ABSTRACT The 21-cm absorption feature reported by the EDGES collaboration is several times stronger than that predicted by traditional astrophysical models. If…”
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A numerical study of 21-cm signal suppression and noise increase in direction-dependent calibration of LOFAR data by Mevius, M, Mertens, F, Koopmans, L V E, Offringa, A R, Yatawatta, S, Brentjens, M A, Chapman, E, Ciardi, B, Gan, H, Gehlot, B K, Ghara, R, Ghosh, A, Giri, S K, Iliev, I T, Mellema, G, Pandey, V N, Zaroubi, S

“…ABSTRACT We investigate systematic effects in direction-dependent gain calibration in the context of the Low-Frequency Array (LOFAR) 21-cm Epoch of…”
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Constraining the intergalactic medium at $z\approx$ 9.1 using LOFAR Epoch of Reionization observations by Ghara, R., Giri, S.K., Mellema, G., Ciardi, B., Zaroubi, S., Iliev, I.T., Koopmans, L.V.E., Chapman, E., Gazagnes, S., Gehlot, B.K., Ghosh, A., Jelic, V., Mertens, F.G., Mondal, R., Schaye, J., Silva, M.B., Asad, K.M.B., Kooistra, R., Mevius, M., Offringa, A.R., Pandey, V.N., Yatawatta, S.

“…We derive constraints on the thermal and ionization states of the intergalactic medium (IGM) at redshift ≈ 9.1 using new upper limits on the 21-cm power…”
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Improved upper limits on the 21-cm signal power spectrum of neutral hydrogen at $\boldsymbol{z \approx 9.1}$ from LOFAR by Mertens, F.G., Mevius, M., Koopmans, L.V.E, Offringa, A.R., Mellema, G., Zaroubi, S., Brentjens, M.A., Gan, H., Gehlot, B.K., Pandey, V.N., Sardarabadi, A.M., Vedantham, H.K., Yatawatta, S., Asad, K.M.B., Ciardi, B., Chapman, E., Gazagnes, S., Ghara, R., Ghosh, A., Giri, S.K., Iliev, I.T., Jelíc, V., Kooistra, R., Mondal, R., Schaye, J., Silva, M.B.

“…A new upper limit on the 21 cm signal power spectrum at a redshift of z ≈ 9.1 is presented, based on 141 h of data obtained with the Low-Frequency Array…”
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Apercal—The Apertif calibration pipeline by Adebahr, B., Schulz, R., Dijkema, T.J., Moss, V.A., Offringa, A.R., Kutkin, A., van der Hulst, J.M., Frank, B.S., Vilchez, N.P.E., Verstappen, J., Adams, E.K., de Blok, W.J.G., Denes, H., Hess, K.M., Lucero, D., Morganti, R., Oosterloo, T., Pisano, D.-J., Ivashina, M.V., van Cappellen, W.A., Connor, L.D., Coolen, A.H.W.M., Damstra, S., Loose, G.M., Maan, Y., Maccagni, F.M., Mika, A., Mulder, H., Oostrum, L.C., Orrú, E., Smits, R., van der Schuur, D., van Leeuwen, J., Vohl, D., Wijnholds, S.J., Ziemke, J.

“…Apertif (APERture Tile In Focus) is one of the Square Kilometre Array (SKA) pathfinder facilities. The Apertif project is an upgrade to the 50-year-old…”
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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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