Browsing by Author "Drabent, A."

Now showing items 1-17 of 17

    • The beautiful mess in Abell 2255 

      Botteon, A.; Brunetti, G.; Weeren, R. J. van; Shimwell, T. W.; Pizzo, R. F.; Cassano, R.; Iacobelli, M.; Gastaldello, F.; Bîrzan, L.; Bonafede, A.; Brüggen, M.; Cuciti, V.; Dallacasa, D.; Gasperin, F. de; Gennaro, G. Di; Drabent, A.; Hardcastle, M. J.; Hoeft, M.; Mandal, S.; Röttgering, H. J. A.; Simionescu, A. (2020-07-07)
      We present LOFAR observations of one of the most spectacular objects in the radio sky: Abell 2255. This is a nearby ($z = 0.0806$) merging galaxy cluster hosting one of the first radio halos ever detected in the intra-cluster ...

    • The contribution of discrete sources to the sky temperature at 144 MHz 

      Hardcastle, M. J.; Shimwell, T. W.; Tasse, C.; Best, P. N.; Drabent, A.; Jarvis, M. J.; Prandoni, I.; Rottgering, H. J. A.; Sabater, J.; Schwarz, D. J. (2021-04-07)
      In recent years, the level of the extragalactic radio background has become a point of considerable interest, with some lines of argument pointing to an entirely new cosmological synchrotron background. The contribution ...

    • Discovery of 24 radio-bright quasars at $4.9 \leq z \leq6.6$ using low-frequency radio observations 

      Gloudemans, A. J.; Duncan, K. J.; Saxena, A.; Harikane, Y.; Hill, G. J.; Zeimann, G. R.; Rottgering, H. J. A.; Yang, D.; Best, P. N.; Banados, E.; Drabent, A.; Hardcastle, M. J.; Hennawi, J. F.; Lansbury, G.; Magliocchetti, M.; Miley, G. K.; Nanni, R.; Shimwell, T. W.; Smith, D. J. B.; Venemans, B.P.; Wagenveld, J. D. (2022-12-31)
      High redshift quasars ($z>5$) that also shine brightly at radio wavelengths are unique signposts of supermassive black hole activity in the early universe. However, bright radio sources at $z\ge5$ are extremely rare and ...

    • The Faraday Rotation Measure Grid of the LOFAR Two-metre Sky Survey: Data Release 2 

      O'Sullivan, S. P.; Shimwell, T. W.; Hardcastle, M. J.; Tasse, C.; Heald, G.; Carretti, E.; Brüggen, M.; Vacca, V.; Sobey, C.; Eck, C. L. Van; Horellou, C.; Beck, R.; Bilicki, M.; Bourke, S.; Botteon, A.; Croston, J. H.; Drabent, A.; Duncan, K.; Heesen, V.; Ideguchi, S.; Kirwan, M.; Lawlor, L.; Mingo, B.; Nikiel-Wroczyński, B.; Piotrowska, J.; Scaife, A. M. M.; Weeren, R. J. van (2023-01-02)
      A Faraday rotation measure (RM) catalogue, or RM Grid, is a valuable resource for the study of cosmic magnetism. Using the second data release (DR2) from the LOFAR Two-metre Sky Survey (LoTSS), we have produced a catalogue ...

    • The galaxy group NGC 507: newly detected AGN remnant plasma transported by sloshing 

      Brienza, M.; Lovisari, L.; Rajpurohit, K.; Bonafede, A.; Gastaldello, F.; Murgia, M.; Vazza, F.; Bonnassieux, E.; Botteon, A.; Brunetti, G.; Drabent, A.; Hardcastle, M. J.; Pasini, T.; Riseley, C. J.; Röttgering, H. J. A.; Shimwell, T.; Simionescu, A.; Weeren, R. J. van (2022-05-06)
      Jets from active galactic nuclei (AGN) are known to recurrently enrich their surrounding medium with mildly-relativistic particles and magnetic fields. Here, we present a detailed multi-frequency analysis of the nearby ...

    • The LOFAR Two-metre Sky Survey - I. Survey Description and Preliminary Data Release 

      Shimwell, T. W.; Röttgering, H. J. A.; Best, P. N.; Williams, W. L.; Dijkema, T. J.; Gasperin, F. de; Hardcastle, M. J.; Heald, G. H.; Hoang, D. N.; Horneffer, A.; Intema, H.; Mahony, E. K.; Mandal, S.; Mechev, A. P.; Morabito, L.; Oonk, J. B. R.; Rafferty, D.; Retana-Montenegro, E.; Sabater, J.; Tasse, C.; Weeren, R. J. van; Brüggen, M.; Brunetti, G.; Chyży, K. T.; Conway, J. E.; Haverkorn, M.; Jackson, N.; Jarvis, M. J.; McKean, J. P.; Miley, G. K.; Morganti, R.; White, G. J.; Wise, M. W.; Bemmel, I. M. van; Beck, R.; Brienza, M.; Bonafede, A.; Rivera, G. Calistro; Cassano, R.; Clarke, A. O.; Cseh, D.; Deller, A.; Drabent, A.; Driel, W. van; Engels, D.; Falcke, H.; Ferrari, C.; Fröhlich, S.; Garrett, M. A.; Harwood, J. J.; Heesen, V.; Hoeft, M.; Horellou, C.; Israel, F. P.; Kapińska, A. D.; Kunert-Bajraszewska, M.; McKay, D. J.; Mohan, N. R.; Orrú, E.; Pizzo, R. F.; Prandoni, I.; Schwarz, D. J.; Shulevski, A.; Sipior, M.; Smith, D. J. B.; Sridhar, S. S.; Steinmetz, M.; Stroe, A.; Varenius, E.; Werf, P. P. van der; Zensus, J. A.; Zwart, J. T. L. (2017-02-09)
      The LOFAR Two-metre Sky Survey (LoTSS) is a deep 120-168 MHz imaging survey that will eventually cover the entire Northern sky. Each of the 3170 pointings will be observed for 8 hrs, which, at most declinations, is sufficient ...

    • The LOFAR Two-metre Sky Survey -- V. Second data release 

      Shimwell, T. W.; Hardcastle, M. J.; Tasse, C.; Best, P. N.; Röttgering, H. J. A.; Williams, W. L.; Botteon, A.; Drabent, A.; Mechev, A.; Shulevski, A.; Weeren, R. J. van; Bester, L.; Brüggen, M.; Brunetti, G.; Callingham, J. R.; Chyży, K. T.; Conway, J. E.; Dijkema, T. J.; Duncan, K.; Gasperin, F. de; Hale, C. L.; Haverkorn, M.; Hugo, B.; Jackson, N.; Mevius, M.; Miley, G. K.; Morabito, L. K.; Morganti, R.; Offringa, A.; Oonk, J. B. R.; Rafferty, D.; Sabater, J.; Smith, D. J. B.; Schwarz, D. J.; Smirnov, O.; O'Sullivan, S. P.; Vedantham, H.; White, G. J.; Albert, J. G.; Alegre, L.; Asabere, B.; Bacon, D. J.; Bonafede, A.; Bonnassieux, E.; Brienza, M.; Bilicki, M.; Bonato, M.; Rivera, G. Calistro; Cassano, R.; Cochrane, R.; Croston, J. H.; Cuciti, V.; Dallacasa, D.; Danezi, A.; Dettmar, R. J.; Gennaro, G. Di; Edler, H. W.; Enßlin, T. A.; Emig, K. L.; Franzen, T. M. O.; García-Vergara, C.; Grange, Y. G.; Gürkan, G.; Hajduk, M.; Heald, G.; Heesen, V.; Hoang, D. N.; Hoeft, M.; Horellou, C.; Iacobelli, M.; Jamrozy, M.; Jelić, V.; Kondapally, R.; Kukreti, P.; Kunert-Bajraszewska, M.; Magliocchetti, M.; Mahatma, V.; Małek, K.; Mandal, S.; Massaro, F.; Meyer-Zhao, Z.; Mingo, B.; Mostert, R. I. J.; Nair, D. G.; Nakoneczny, S. J.; Nikiel-Wroczyński, B.; Orrú, E.; Pajdosz-Śmierciak, U.; Pasini, T.; Prandoni, I.; Piggelen, H. E. van; Rajpurohit, K.; Retana-Montenegro, E.; Riseley, C. J.; Rowlinson, A.; Saxena, A.; Schrijvers, C.; Sweijen, F.; Siewert, T. M.; Timmerman, R.; Vaccari, M.; Vink, J.; West, J. L.; Wołowska, A.; Zhang, X.; Zheng, J. (2022-02-25)
      In this data release from the ongoing LOw-Frequency ARray (LOFAR) Two-metre Sky Survey we present 120a 168 MHz images covering 27% of the northern sky. Our coverage is split into two regions centred at approximately 12h45m ...

    • The LOFAR Two-Metre Sky Survey : VI. Optical identifications for the second data release 

      Hardcastle, M. J.; Horton, M. A.; Williams, W. L.; Duncan, K. J.; Alegre, L.; Barkus, B.; Croston, J. H.; Dickinson, H.; Osinga, E.; Röttgering, H. J. A.; Sabater, J.; Shimwell, T. W.; Smith, D. J. B.; Best, P. N.; Botteon, A.; Brüggen, M.; Drabent, A.; Gasperin, F. de; Gürkan, G.; Hajduk, M.; Hale, C. L.; Hoeft, M.; Jamrozy, M.; Kunert-Bajraszewska, M.; Kondapally, R.; Magliocchetti, M.; Mahatma, V. H.; Mostert, R. I. J.; O'Sullivan, S. P.; Pajdosz-Śmierciak, U.; Petley, J.; Pierce, J. C. S.; Prandoni, I.; Schwarz, D. J.; Shulewski, A.; Siewert, T. M.; Stott, J. P.; Tang, H.; Vaccari, M.; Zheng, X.; Bailey, T.; Desbled, S.; Goyal, A.; Gonano, V.; Hanset, M.; Kurtz, W.; Lim, S. M.; Mielle, L.; Molloy, C. S.; Roth, R.; Terentev, I. A.; Torres, M. (2023-10-01)
      The second data release of the LOFAR Two-Metre Sky Survey (LoTSS) covers 27% of the northern sky, with a total area of ∼5700 deg1. The high angular resolution of LOFAR with Dutch baselines (6 arcsec) allows us to carry out ...

    • The LOFAR view of giant, early-type galaxies: radio emission from active nuclei and star formation 

      Capetti, A.; Brienza, M.; Balmaverde, B.; Best, R. D. P. N.; Baldi, R. D.; Drabent, A.; Gurkan, G.; Rottgering, H. J. A.; Tasse, C.; Webster, B. (2022-02-17)
      We studied the properties and the origin of the radio emission in the most luminous, early-type galaxies (ETGs) in the nearby Universe (MK ≤ −25, recession velocity ≤7500 km s−1), as seen by the 150 MHz Low-Frequency ARray ...

    • Low frequency radio properties of the $z>5$ quasar population 

      Gloudemans, A. J.; Duncan, K. J.; Röttgering, H. J. A.; Shimwell, T. W.; Venemans, B. P.; Best, P. N.; Brüggen, M.; Rivera, G. Calistro; Drabent, A.; Hardcastle, M. J.; Miley, G. K.; Schwarz, D. J.; Saxena, A.; Smith, D. J. B.; Williams, W. L. (2021-12-31)
      Optically luminous quasars at z > 5 are important probes of super-massive black hole (SMBH) formation. With new and future radio facilities, the discovery of the brightest low-frequency radio sources in this epoch would ...

    • Nearby galaxies in the LOFAR Two-metre Sky Survey : I. Insights into the non-linearity of the radio–SFR relation 

      Heesen, V.; Staffehl, M.; Basu, A.; Beck, R.; Stein, M.; Tabatabaei, F. S.; Hardcastle, M. J.; Chyży, K. T.; Shimwell, T. W.; Adebahr, B.; Beswick, R.; Bomans, D. J.; Botteon, A.; Brinks, E.; Brüggen, M.; Dettmar, R. -J.; Drabent, A.; Gasperin, F. de; Gürkan, G.; Heald, G. H.; Horellou, C.; Nikiel-Wroczynski, B.; Paladino, R.; Piotrowska, J.; Röttgering, H. J. A.; Smith, D. J. B.; Tasse, C. (2022-08-08)
      Context. Cosmic rays and magnetic fields are key ingredients in galaxy evolution, regulating both stellar feedback and star formation. Their properties can be studied with low-frequency radio continuum observations, free ...

    • The Planck clusters in the LOFAR sky. I. LoTSS-DR2 new detections and sample overview 

      Botteon, A.; Shimwell, T. W.; Cassano, R.; Cuciti, V.; Zhang, X.; Bruno, L.; Camillini, L.; Natale, R.; Jones, A.; Gastaldello, F.; Simionescu, A.; Rossetti, M.; Akamatsu, H.; Weeren, R. J. van; Brunetti, G.; Brüggen, M.; Groenveld, C.; Hoang, D. N.; Hardcastle, M. J.; Ignesti, A.; Gennaro, G. Di; Bonafede, A.; Drabent, A.; Röttgering, H. J. A.; Hoeft, M.; Gasperin, F. de (2022-04-30)
      Context. Relativistic electrons and magnetic fields permeate the intra-cluster medium (ICM) and manifest themselves as diffuse sources of synchrotron emission observable at radio wavelengths, namely radio halos and radio ...

    • The population of M dwarfs observed at low radio frequencies 

      Callingham, J. R.; Vedantham, H. K.; Shimwell, T. W.; Pope, B. J. S.; Davis, I. E.; Best, P. N.; Hardcastle, M. J.; Rottgering, H. J. A.; Sabater, J.; Tasse, C.; Weeren, R. J. van; Williams, W. L.; Zarka, P.; Gasperin, F. de; Drabent, A. (2021-10-11)
      Coherent low-frequency (≲200 MHz) radio emission from stars encodes the conditions of the outer corona, mass-ejection events and space weather 1–5. Previous low-frequency searches for radio-emitting stellar systems have ...

    • Star Formation and AGN Feedback in the Local Universe: Combining LOFAR and MaNGA 

      Mulcahey, C. R.; Leslie, S. K.; Jackson, T. M.; Young, J. E.; Prandoni, I.; Hardcastle, M. J.; Roy, N.; Małek, K.; Magliocchetti, M.; Bonato, M.; Röttgering, H. J. A.; Drabent, A. (2022-09-21)
      The effect of active galactic nuclei (AGN) on their host galaxies – in particular their levels of star formation – remains one of the key outstanding questions of galaxy evolution. Successful cosmological models of galaxy ...

    • Sub-arcsecond imaging with the International LOFAR Telescope : I. Foundational calibration strategy and pipeline 

      Morabito, L. K.; Jackson, N. J.; Mooney, S.; Sweijen, F.; Badole, S.; Kukreti, P.; Venkattu, D.; Groeneveld, C.; Kappes, A.; Bonnassieux, E.; Drabent, A.; Iacobelli, M.; Croston, J. H.; Best, P. N.; Bondi, M.; Callingham, J. R.; Conway, J. E.; Deller, A. T.; Hardcastle, M. J.; McKean, J. P.; Miley, G. K.; Moldon, J.; Röttgering, H. J. A.; Tasse, C.; Shimwell, T. W.; Weeren, R. J. van; Anderson, J. M.; Asgekar, A.; Avruch, I. M.; Bemmel, I. M. van; Bentum, M. J.; Bonafede, A.; Brouw, W. N.; Butcher, H. R.; Ciardi, B.; Corstanje, A.; Coolen, A.; Damstra, S.; Gasperin, F. de; Duscha, S.; Eislöffel, J.; Engels, D.; Falcke, H.; Garrett, M. A.; Griessmeier, J.; Gunst, A. W.; Haarlem, M. P. van; Hoeft, M.; Horst, A. J. van der; Jütte, E.; Kadler, M.; Koopmans, L. V. E.; Krankowski, A.; Mann, G.; Nelles, A.; Oonk, J. B. R.; Orru, E.; Paas, H.; Pandey, V. N.; Pizzo, R. F.; Pandey-Pommier, M.; Reich, W.; Rothkaehl, H.; Ruiter, M.; Schwarz, D. J.; Shulevski, A.; Soida, M.; Tagger, M.; Vocks, C.; Wijers, R. A. M. J.; Wijnholds, S. J.; Wucknitz, O.; Zarka, P.; Zucca, P. (2022-02-28)
      The International LOFAR Telescope is an interferometer with stations spread across Europe. With baselines of up to ∼2000 km, LOFAR has the unique capability of achieving sub-arcsecond resolution at frequencies below 200 ...

    • Subarcsecond view on the high-redshift blazar GB 1508+5714 by the International LOFAR Telescope 

      Kappes, A.; Burd, P. R.; Kadler, M.; Ghisellini, G.; Bonnassieux, E.; Perucho, M.; Brüggen, Marcus; Cheung, C. C.; Ciardi, B.; Gallo, E.; Haardt, F.; Morabito, Leah K.; Sbarrato, T.; Drabent, A.; Harwood, J.; Jackson, N. J.; Moldon, Javier (2022-07-12)
      Context. Studies of the most distant active galactic nuclei (AGNs) allow us to test our current understanding of the physics present in radio-jetted AGNs across a range of environments, and probe their interactions with ...

    • V-LoTSS: The circularly polarised LOFAR Two-metre Sky Survey 

      Callingham, J.~R.; Shimwell, T.~W.; Vedantham, H.~K.; Bassa, C.~G.; O'Sullivan, S.~P.; Yiu, T.~W.~H.; Bloot, S.; Best, P.~N.; Hardcastle, M.~J.; Haverkorn, M.; Kavanagh, R.~D.; Lamy, L.; Pope, B.~J.~S.; Röttgering, H.~J.~A.; Schwarz, D.~J.; Tasse, C.; van Weeren, R.~J.; White, G.~J.; Zarka, P.; Bomans, D.~J.; Bonafede, A.; Bonato, M.; Botteon, A.; Bruggen, M.; Chyży, K.~T.; Drabent, A.; Emig, K.~L.; Gloudemans, A.~J.; Gürkan, G.; Hajduk, M.; Hoang, D.~N.; Hoeft, M.; Iacobelli, M.; Kadler, M.; Kunert-Bajraszewska, M.; Mingo, B.; Morabito, L.~K.; Nair, D.~G.; Pérez-Torres, M.; Ray, T.~P.; Riseley, C.~J.; Rowlinson, A.; Shulevski, A.; Sweijen, F.; Timmerman, R.; Vaccari, M.; Zheng, J. (2023-02-17)
      We present the detection of 68 sources from the most sensitive radio survey in circular polarisation conducted to date. We used the second data release of the 144 MHz LOFAR Two-metre Sky Survey to produce circularly polarised ...