Browsing by Author "Sweijen, Frits"

Now showing items 1-5 of 5

    • High-resolution international LOFAR observations of 4C~43.15 -- Spectral ages and injection indices in a high-z radio galaxy 

      Sweijen, Frits; Morabito, Leah K.; Harwood, Jeremy; Weeren, Reinout J. van; Röttgering, Huub J. A.; Callingham, Joseph R.; Jackson, Neal; Miley, George; Moldon, Javier (2022-02-01)
      It has long been known that radio sources with the steepest spectra are preferentially associated with the most distant galaxies, the α - z relation, but the reason for this relation is an open question. The spatial ...

    • The resolved jet of 3C 273 at 150 MHz : Sub-arcsecond imaging with the LOFAR international baselines 

      Harwood, Jeremy J.; Mooney, Sean; Morabito, Leah K.; Quinn, John; Sweijen, Frits; Groeneveld, Christian; Bonnassieux, Etienne; Kappes, Alexander; Moldon, Javier (2022-02-01)
      Context. Since its discovery in 1963, 3C 273 has become one of the most widely studied quasars with investigations spanning the electromagnetic spectrum. While much has therefore been discovered about this historically ...

    • Spectral analysis of spatially-resolved 3C295 (sub-arcsecond resolution) with the International LOFAR Telescope 

      Bonnassieux, Etienne; Sweijen, Frits; Brienza, Marisa; Rajpurohit, Kamlesh; Riseley, Christopher John; Bonafede, Annalisa; Jackson, Neal; Morabito, Leah K.; Brunetti, Gianfranco; Harwood, Jeremy; Kappes, Alex; Rottgering, Huub J.; Tasse, Cyril; Weeren, Reinout van (2022-02-25)
      3C295 is a bright, compact steep spectrum source with a well-studied integrated radio spectral energy distribution (SED) from 132 MHz to 15 GHz. However, spatially resolved spectral studies have been limited due to a lack ...

    • Sub-arcsecond imaging with the International LOFAR Telescope. II. Completion of the LOFAR Long-Baseline Calibrator Survey 

      Jackson, Neal; Badole, Shruti; Chhetri, Rajan; Prusis, Kaspars; Nikolajevs, Atvars; Morabito, Leah; Brentjens, Michiel; Sweijen, Frits; Iacobelli, Marco; Orrù, Emanuela; Sluman, J.; Blaauw, R.; Mulder, H.; Dijk, P. van; Mooney, Sean; Deller, Adam; Moldon, Javier; Callingham, J. R.; Harwood, Jeremy; Hardcastle, Martin; Heald, George; Drabent, Alexander; McKean, J. P.; Asgekar, A.; Avruch, I. M.; Bentum, M. J.; Bonafede, A.; Brouw, W. N.; Brüggen, M.; Butcher, H. R.; Ciardi, B.; Coolen, A.; Corstanje, A.; Damstra, S.; Duscha, S.; Eislöffel, J.; Falcke, H.; Garrett, M.; Gasperin, F. de; Griessmeier, J. -M.; Gunst, A. W.; Haarlem, M. P. van; Hoeft, M.; Horst, A. J. van der; Jütte, E.; Koopmans, L. V. E.; Krankowski, A.; Maat, P.; Mann, G.; Miley, G. K.; Nelles, A.; Norden, M.; Paas, M.; Pandey, V. N.; Pandey-Pommier, M.; Pizzo, R. F.; Reich, W.; Rothkaehl, H.; Rowlinson, A.; Ruiter, M.; Shulevski, A.; Schwarz, D. J.; Smirnov, O.; Tagger, M.; Vocks, C.; Weeren, R. J. van; Wijers, R.; Wucknitz, O.; Zarka, P.; Zensus, J. A.; Zucca, P. (2022-02-01)
      The Low-Frequency Array (LOFAR) Long-Baseline Calibrator Survey (LBCS) was conducted between 2014 and 2019 in order to obtain a set of suitable calibrators for the LOFAR array. In this paper, we present the complete survey, ...

    • Unmasking the history of 3C 293 with LOFAR sub‐arcsecond imaging 

      Kukreti, Pranav; Morganti, Raffaella; Shimwell, Timothy W.; Morabito, Leah K.; Beswick, Robert J.; Brienza, Marisa; Hardcastle, Martin J.; Sweijen, Frits; Jackson, Neal; Miley, George K.; Moldon, Javier; Oosterloo, Tom; Gasperin, Francesco de (2021-12-07)
      Active galactic nuclei show episodic activity, which can be evident in galaxies that exhibit restarted radio jets. These restarted jets can interact with their environment, leaving signatures in the radio spectral energy ...