Now showing items 41-60 of 62

    • LOFAR/H-ATLAS: A deep low-frequency survey of the Herschel-ATLAS North Galactic Pole field 

      Hardcastle, M. J.; Gürkan, G.; Weeren, R. J. van; Williams, W. L.; Best, P. N.; Gasperin, F. de; Rafferty, D. A.; Read, S. C.; Sabater, J.; Shimwell, T. W.; Smith, D. J. B.; Tasse, C.; Bourne, N.; Brienza, M.; Brüggen, M.; Brunetti, G.; Chyży, K. T.; Conway, J.; Dunne, L.; Eales, S. A.; Maddox, S. J.; Jarvis, M. J.; Mahony, E. K.; Morganti, R.; Prandoni, I.; Röttgering, H. J. A.; Valiante, E.; White, G. J. (2016-10-21)
      We present LOFAR High-Band Array (HBA) observations of the Herschel-ATLAS North Galactic Pole survey area. The survey we have carried out, consisting of four pointings covering around 142 square degrees of sky in the ...
    • LoTSS DR1 : Double-double radio galaxies in the HETDEX field 

      Mahatma, V. H.; Hardcastle, M. J.; Williams, W. L.; Best, P. N.; Croston, J. H.; Duncan, K.; Mingo, B.; Morganti, R.; Brienza, M.; Cochrane, R. K.; Gürkan, G.; Harwood, J. J.; Jarvis, M. J.; Jamrozy, M.; Jurlin, N.; Morabito, Leah K.; Röttgering, H. J. A.; Sabater, J.; Shimwell, T. W.; Smith, D. J. B.; Shulevski, A.; Tasse, C. (2018-11-20)
      Double-double radio galaxies (DDRGs) represent a short but unique phase in the life-cycle of some of the most powerful radio-loud active galactic nuclei (RLAGN). These galaxies display large-scale remnant radio plasma in ...
    • The LoTSS view of radio AGN in the local Universe. The most massive galaxies are always switched on 

      Sabater, J.; Best, P.N.; Hardcastle, M. J.; Shimwell, T. W.; Tasse, C.; Williams, W. L.; Brüggen, M.; Cochrane, R. K.; Croston, J. H.; Gasperin, F. de; Duncan, K. J.; Gürkan, G.; Mechev, A. P.; Morabito, Leah K.; Prandoni, I.; Röttgering, H. J. A.; Smith, D. J. B.; Harwood, J. J.; Mingo, B.; Mooney, S.; Saxena, A. (2018-11-15)
      This paper presents a study of the local radio source population, by cross-comparing the data from the first data release (DR1) of the LOFAR Two-Metre Sky Survey (LoTSS) with the Sloan Digital Sky Survey (SDSS) DR7 main ...
    • LoTSS/HETDEX: Disentangling star formation and AGN activity in gravitationally-lensed radio-quiet quasars 

      Stacey, H. R.; McKean, J. P.; Jackson, N. J.; Best, P. N.; Rivera, G. Calistro; Callingham, J. R.; Duncan, K. J.; Gürkan, G.; Hardcastle, M. J.; Iacobelli, M.; Mechev, A. P.; Morabito, L. K.; Prandoni, I.; Röttgering, H. J. A.; Sabater, J.; Shimwell, T. W.; Tasse, C.; Williams, W. L. (2018-11-19)
      Determining the star-forming properties of radio-quiet quasars is important for understanding the co-evolution of star formation and black hole accretion. Here, we present the detection of the gravitationally-lensed ...
    • Low-frequency observations of the Giant Radio Galaxy NGC 6251 

      Cantwell, T. M.; Bray, J. D.; Croston, J. H.; Scaife, A. M. M.; Mulcahy, D. D.; Best, P. N.; Bruggen, M.; Brunetti, G.; Callingham, J. R.; Clarke, A. O.; Hardcastle, M. J.; Harwood, J. J.; Heald, G.; Heesen, V.; Iacobelli, M.; Jamrozy, M.; Morganti, R.; Orru, E.; O'Sullivan, S. P.; Riseley, C. J.; Rottgering, H. J. A.; Shulevski, A.; Sridhar, S. S.; Tasse, C.; Eck, C. L. Van (2020-06-01)
      We present LOFAR observations at 150 MHz of the borderline FRI/FRII giant radio galaxy NGC 6251. This paper presents the most sensitive and highest-resolution images of NGC 6251 at these frequencies to date, revealing for ...
    • Low-frequency radio spectra of submillimetre galaxies in the Lockman Hole 

      Ramasawmy, J.; Geach, J. E.; Hardcastle, M. J.; Best, P. N.; Bonato, M.; Bondi, M.; Rivera, G. Calistro; Cochrane, R. K.; Conway, J. E.; Coppin, K.; Duncan, K. J.; Dunlop, J. S.; Franco, M.; García-Vergara, C.; Jarvis, M. J.; Kondapally, R.; McCheyne, I.; Prandoni, I.; Röttgering, H. J. A.; Smith, D. J. B.; Tasse, C.; Wang, L. (2021-04-19)
      We investigate the radio properties of a sample of 53 sources selected at 850 $\mu$m from the SCUBA-2 Cosmology Legacy Survey using new deep, low-frequency radio imaging of the Lockman Hole field from the Low Frequency ...
    • MIGHTEE: Are giant radio galaxies more common than we thought? 

      Delhaize, J.; Heywood, I.; Prescott, M.; Jarvis, M. J.; Delvecchio, I.; Whittam, I. H.; White, S. V.; Hardcastle, M. J.; Hale, C. L.; Afonso, J.; Ao, Y.; Brienza, M.; Brueggen, M.; Collier, J. D.; Daddi, E.; Glowacki, M.; Maddox, N.; Morabito, L. K.; Prandoni, I.; Randriamanakoto, Z.; Sekhar, S.; An, Fangxia; Adams, N. J.; Blyth, S.; Bowler, R. A. A.; Leeuw, L.; Marchetti, L.; Randriamampandry, S. M.; Thorat, K.; Seymour, N.; Smirnov, O.; Taylor, A. R.; Tasse, C.; Vaccari, M. (2020-12-14)
      We report the discovery of two new giant radio galaxies (GRGs) using the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey. Both GRGs were found within a 1 deg^2 region inside the COSMOS field. ...
    • MIGHTEE: total intensity radio continuum imaging and the COSMOS / XMM-LSS Early Science fields 

      Heywood, I.; Jarvis, M. J.; Hale, C. L.; Whittam, I. H.; Bester, H. L.; Hugo, B.; Kenyon, J. S.; Prescott, M.; Smirnov, O. M.; Tasse, C.; Afonso, J. M.; Best, P. N.; Collier, J. D.; Deane, R. P.; Frank, B. S.; Hardcastle, M. J.; Knowles, K.; Maddox, N.; Murphy, E. J.; Prandoni, I.; Randriamampandry, S. M.; Santos, M. G.; Sekhar, S.; Tabatabaei, F.; Taylor, A. R.; Thorat, K. (2021-10-21)
      MIGHTEE is a galaxy evolution survey using simultaneous radio continuum, spectro-polarimetry, and spectral line observations from the South African MeerKAT telescope. When complete, the survey will image $\sim$20 deg$^{2}$ ...
    • 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 ...
    • NGC 326: X-shaped no more 

      Hardcastle, M. J.; Croston, J. H.; Shimwell, T. W.; Tasse, C.; Gurkan Uygun, Gulay; Morganti, R.; Murgia, M.; Rottgering, H. J. A.; Weeren, R. J. van; Williams, W. L. (2019-09-01)
      We present new 144-MHz LOFAR observations of the prototypical `X-shaped' radio galaxy NGC 326, which show that the formerly known wings of the radio lobes extend smoothly into a large-scale, complex radio structure. We ...
    • A population of galaxy-scale jets discovered using LOFAR 

      Webster, B.; Croston, J. H.; Mingo, B.; Baldi, R. D.; Barkus, B.; Gurkan, G.; Hardcastle, M. J.; Morganti, R.; Rottgering, H. J. A.; Sabater, J.; Shimwell, T. W.; Tasse, C.; White, G. J. (2020-11-05)
      The effects of feedback from high luminosity radio-loud AGN have been extensively discussed in the literature, but feedback from low-luminosity radio-loud AGN is less well understood. The advent of high sensitivity, high ...
    • 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 ...
    • Possible discovery of Calvera's supernova remnant 

      Arias, M.; Botteon, A.; Bassa, C. G.; Jagt, S. van der; Weeren, R. J. van; O'Sullivan, S. P.; Bosschaart, Q.; Dullaart, R. S.; Hardcastle, M. J.; Hessels, J. W. T.; Shimwell, T.; Slob, M. M.; Sturm, J. A.; Tasse, C.; Theijssen, N. C. M. A.; Vink, J. (2022-11-01)
      We report the discovery of a ring of low surface brightness radio emission around the Calvera pulsar, a high Galactic latitude, isolated neutron star, in the LOFAR Two-metre Sky Survey (LoTSS). It is centered at α = ...
    • Radio-loud AGN in the first LoTSS data release: The lifetimes and environmental impact of jet-driven sources 

      Hardcastle, M. J.; Williams, W. L.; Best, P. N.; Croston, J. H.; Duncan, K. J.; Rottgering, H. J. A.; Sabater, J.; Shimwell, T. W.; Tasse, C.; Callingham, J. R.; Cochrane, R. K.; Gasperin, F. de; Gurkan, G.; Jarvis, M. J.; Mahatma, V.; Miley, G. K.; Mingo, B.; Mooney, S.; Morabito, L. K.; O'Sullivan, S. P.; Prandoni, I.; Shulevski, A.; Smith, D. J. B. (2018-11-19)
      We constructed a sample of 23,344 radio-loud active galactic nuclei (RLAGN) from the catalogue derived from the LOFAR Two-Metre Sky Survey (LoTSS) survey of the HETDEX Spring field. Although separating AGN from star-forming ...
    • Remnant radio-loud AGN in the Herschel-ATLAS field 

      Mahatma, V. H.; Hardcastle, M. J.; Williams, W. L.; Brienza, M.; Bruggen, M.; Croston, J. H.; Gurkan, G.; Harwood, J. J.; Kunert-Bajraszewska, M.; Morganti, R.; Rottgering, H. J. A.; Shimwell, T. W.; Tasse, C. (2018-04-21)
      Only a small fraction of observed active galactic nuclei (AGN) display large-scale radio emission associated with jets, yet these radio-loud AGN have become increasingly important in models of galaxy evolution. In determining ...
    • Revived Fossil Plasma Sources in Galaxy Clusters 

      Mandal, S.; Intema, H. T.; Weeren, R. J. van; Shimwell, T. W.; Botteon, A.; Brunetti, G.; Gasperin, F. de; Brüggen, M.; Gennaro, G. Di; Kraft, R.; Röttgering, H. J. A.; Hardcastle, M.; Tasse, C. (2020-01-28)
      It is well established that particle acceleration by shocks and turbulence in the intra-cluster medium can produce cluster-scale synchrotron emitting sources. However, the detailed physics of these particle acceleration ...
    • SKA Science Data Challenge 2: analysis and results 

      Hartley, P.; Bonaldi, A.; Braun, R.; Aditya, J. N. H. S.; Aicardi, S.; Alegre, L.; Chakraborty, A.; Chen, X.; Choudhuri, S.; Clarke, A. O.; Coles, J.; Collinson, J. S.; Cornu, D.; Darriba, L.; Veneri, M. Delli; Forbrich, J.; Fraga, B.; Galan, A.; Garrido, J.; Gubanov, F.; Håkansson, H.; Hardcastle, M. J.; Heneka, C.; Herranz, D.; Hess, K. M.; Jagannath, M.; Jaiswal, S.; Jurek, R. J.; Korber, D.; Kitaeff, S.; Kleiner, D.; Lao, B.; Lu, X.; Mazumder, A.; Moldón, J.; Mondal, R.; Ni, S.; Önnheim, M.; Parra, M.; Patra, N.; Peel, A.; Salomé, P.; Sánchez-Expósito, S.; Sargent, M.; Semelin, B.; Serra, P.; Shaw, A. K.; Shen, A. X.; Sjöberg, A.; Smith, L.; Soroka, A.; Stolyarov, V.; Tolley, E.; Toribio, M. C.; Hulst, J. M. van der; Sadr, A. Vafaei; Verdes-Montenegro, L.; Westmeier, T.; Yu, K.; Yu, L.; Zhang, L.; Zhang, X.; Zhang, Y.; Alberdi, A.; Ashdown, M.; Bom, C. R.; Brüggen, M.; Cannon, J.; Chen, R.; Combes, F.; Conway, J.; Courbin, F.; Ding, J.; Fourestey, G.; Freundlich, J.; Gao, L.; Gheller, C.; Guo, Q.; Gustavsson, E.; Jirstrand, M.; Jones, M. G.; Józsa, G.; Kamphuis, P.; Kneib, J. -P.; Lindqvist, M.; Liu, B.; Liu, Y.; Mao, Y.; Marchal, A.; Márquez, I.; Meshcheryakov, A.; Olberg, M.; Oozeer, N.; Pandey-Pommier, M.; Pei, W.; Peng, B.; Sabater, J.; Sorgho, A.; Starck, J. L.; Tasse, C.; Wang, A.; Wang, Y.; Xi, H.; Yang, X.; Zhang, H.; Zhang, J.; Zhao, M.; Zuo, S. (2023-08-31)
      The Square Kilometre Array Observatory (SKAO) will explore the radio sky to new depths in order to conduct transformational science. SKAO data products made available to astronomers will be correspondingly large and complex, ...
    • A snapshot of the oldest AGN feedback phases 

      Brienza, M.; Shimwell, T. W.; Gasperin, F. de; Bikmaev, I.; Bonafede, A.; Botteon, A.; Brüggen, M.; Brunetti, G.; Burenin, R.; Capetti, A.; Churazov, E.; Hardcastle, M. J.; Khabibullin, I.; Lyskova, N.; R öttgering, H. J. A.; Sunyaev, R.; Weeren, R. J. van; Gastaldello, F.; Mandal, S.; Purser, S.; Simionescu, A.; Tasse, C. (2021-10-18)
      Active Galactic Nuclei (AGN) inject large amounts of energy into their host galaxies and surrounding environment, shaping their properties and evolution. In particular, AGN jets inflate cosmic-ray lobes, which can rise ...
    • 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 ...
    • The origin of radio emission in broad absorption line quasars: Results from the LOFAR Two-metre Sky Survey 

      Morabito, L. K.; Matthews, J. H.; Best, P. N.; Gürkan, G.; Jarvis, M. J.; Prandoni, I.; Duncan, K. J.; Hardcastle, M. J.; Kunert-Bajraszewska, M.; Mechev, A. P.; Mooney, S.; Sabater, J.; Röttgering, H. J. A.; Shimwell, T. W.; Smith, D. J. B.; Tasse, C.; Williams, W. L. (2018-08-16)
      We present a study of the low-frequency radio properties of broad absorption line quasars (BALQSOs) from the LOFAR Two-metre Sky-Survey Data Release 1 (LDR1). The value-added LDR1 catalogue contains Pan-STARRS counterparts, ...