Now showing items 21-40 of 46

    • LOFAR imaging of Cygnus A - direct detection of a turnover in the hotspot radio spectra 

      McKean, J. P.; Godfrey, L. E H; Vegetti, S.; Wise, Michael W.; Morganti, R.; Hardcastle, M. J.; Rafferty, D.; Avruch, I. M.; Beck, R.; Bell, M. E.; Bemmel, I. M. van; Bentum, M. J.; Bernardi, G.; Best, Philip; Blaauw, R.; Bonafede, A.; Breitling, F.; Broderick, J. W.; Brüggen, Marcus; Cerrigone, L.; Ciardi, B.; De Gasperin, Francesco; Deller, A.; Duscha, S.; Engels, D.; Falcke, H.; Fallows, R. A.; Frieswijk, W.; Garrett, M.A.; Grießmeier, J. -M.; Haarlem, M. P. van; Heald, G.; Hoeft, Matthias; van der, HorstA J.; Iacobelli, M.; Interna, H.; Juette, E.; Karastergiou, A.; Kondratiev, V. I.; Koopmans, L. V E; Kuniyoshi, M.; Kuper, G.; Van Leeuwen, J.; Maat, P.; Mann, R. G.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Mulcahy, D. D.; Munk, H.; Nelles, A.; Orru, E.; Paas, H.; Pandey-Pommier, M.; Pietka, M.; Pizzo, R.; Polatidis, A. G.; Reich, W.; Rottgering, H. J. A.; Rowlinson, A.; Scaife, A. M M; Serylak, M.; Shulevski, Alexander; Sluman, J.; Smirnov, O.; Steinmetz, M.; Stewart, A. J.; Swinbank, J.; Tagger, M.; Thoudam, S.; Toribio, M. C.; Vermeulen, R.; Vocks, C.; Van Weeren, R. J.; Wucknitz, O.; Yatawatta, S.; Zarka, P. (2016-12-01)
      The low-frequency radio spectra of the hotspots within powerful radio galaxies can provide valuable information about the physical processes operating at the site of the jet termination. These processes are responsible for ...
    • The LOFAR LBA Sky Survey I. survey description and preliminary data release 

      Gasperin, F. de; Williams, W. L.; Best, P.; Bruggen, M.; Brunetti, G.; Cuciti, V.; Dijkema, T. J.; Hardcastle, M. J.; Norden, M. J.; Offringa, A.; Shimwell, T.; Weeren, R. van; Bomans, D.; Bonafede, A.; Botteon, A.; Callingham, J. R.; Cassano, R.; Chyzy, K. T.; Emig, K. L.; Edler, H.; Haverkorn, M.; Heald, G.; Heesen, V.; Iacobelli, M.; Intema, H. T.; Kadler, M.; Malek, K.; Mevius, M.; Miley, G.; Mingo, B.; Morabito, L. K.; Sabater, J.; Morganti, R.; Orru, E.; Pizzo, R.; Prandoni, I.; Shulevski, A.; Tasse, C.; Vaccari, M.; Zarka, P.; Rottgering, H. (2021-02-17)
      Context. The LOw Frequency ARray (LOFAR)istheonlyradiotelescopethatispresentlycapableofhigh-sensitivity,high-resolution (i.e. < 1mJybeam−1 and < 1500) observations at ultra-low frequencies(< 100MHz). To utilise these ...
    • The LOFAR Multifrequency Snapshot Sky Survey (MSSS) : I. Survey description and first results 

      Heald, G. H.; Pizzo, R. F.; Orrú, E.; Breton, R. P.; Carbone, D.; Ferrari, C.; Hardcastle, M.J.; Jurusik, W.; Macario, G.; Mulcahy, D.; Rafferty, D.; Asgekar, A.; Brentjens, M.; Fallows, R. A.; Frieswijk, W.; Toribio, M. C.; Adebahr, B.; Arts, M.; Bell, M. R.; Bonafede, A.; Bray, J.; Broderick, J.; Cantwell, T.; Carroll, P.; Cendes, Y.; Clarke, A. O.; Croston, J. H.; Daiboo, S.; De Gasperin, F.; Gregson, J.; Harwood, J.; Hassall, T.; Heesen, V.; Horneffer, A.; van der Horst, A.J.; Iacobelli, M.; Jelić, V.; Jones, D.; Kant, D.; Kokotanekov, G.; Martin, P.; McKean, J. P.; Morabito, L. K.; Nikiel-Wroczyński, B.; Offringa, A.; Pandey, V. N.; Pandey-Pommier, M.; Pietka, M.; Pratley, L.; Riseley, C.; Rowlinson, A.; Sabater, J.; Scaife, A. M. M.; Scheers, L. H. A.; Sendlinger, K.; Shulevski, A.; Sipior, M.; Sobey, C.; Stewart, A. J.; Stroe, A.; Swinbank, J.; Tasse, C.; Trüstedt, J.; Varenius, E.; Van Velzen, S.; Vilchez, N.; Van Weeren, R. J.; Wijnholds, S.; Williams, W. L.; de Bruyn, A. G.; Nijboer, R.; Wise, M.; Alexov, A.; Anderson, J.; Avruch, I. M.; Beck, R.; Bell, M. E.; Van Bemmel, I.; Bentum, M. J.; Bernardi, G.; Best, P.; Breitling, F.; Brouw, W. N.; Brüggen, M.; Butcher, H. R.; Ciardi, B.; Conway, J. E.; De Geus, E.; De Jong, A.; De Vos, M.; Deller, A.; Dettmar, R. J.; Duscha, S.; Eislöffel, J.; Engels, D.; Falcke, H.; Fender, R.; Garrett, M.A.; Grießmeier, J.; Gunst, A. W.; Hamaker, J. P.; Hessels, J. W. T.; Hoeft, M.; Hörandel, J.; Holties, H. A.; Intema, H.; Jackson, N. J.; Jütte, E.; Karastergiou, A.; Klijn, W. F. A.; Kondratiev, V. I.; Koopmans, L. V. E.; Kuniyoshi, M.; Kuper, G.; Law, C.; Van Leeuwen, J.; Loose, M.; Maat, P.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Mevius, M.; Miller-Jones, J. C A; Morganti, R.; Munk, H.; Nelles, A.; Noordam, J. E.; Norden, M. J.; Paas, H.; Polatidis, A. G.; Reich, W.; Renting, A.; Röttgering, H.; Schoenmakers, A.; Schwarz, D.; Sluman, J.; Smirnov, O.; Stappers, B. W.; Steinmetz, M.; Tagger, M.; Tang, Y.; Ter Veen, S.; Thoudam, S.; Vermeulen, R.; Vocks, C.; Vogt, C.; Wijers, R.A.M.J.; Wucknitz, O.; Yatawatta, S.; Zarka, P. (2015-10-01)
      We present the Multifrequency Snapshot Sky Survey (MSSS), the first northern-sky Low Frequency Array (LOFAR) imaging survey. In this introductory paper, we first describe in detail the motivation and design of the survey. ...
    • LOFAR reveals the giant : A low-frequency radio continuum study of the outflow in the nearby FR I radio galaxy 3C 31 

      Heesen, V.; Croston, J. H.; Morganti, R.; Hardcastle, M. J.; Stewart, A. J.; Best, P. N.; Broderick, J. W.; Brüggen, M.; Brunetti, G.; Chyzy, K. T.; Harwood, J. J.; Haverkorn, M.; Hess, K. M.; Intema, H. T.; Jamrozy, M.; Kunert-Bajraszewska, M.; McKean, J. P.; Orrú, E.; Röttgering, H. J.A.; Shimwell, T. W.; Shulevski, A.; White, G. J.; Wilcots, E. M.; Williams, W. L. (2018-03-11)
      We present a deep, low-frequency radio continuum study of the nearby Fanaroff-Riley class I (FR I) radio galaxy 3C 31 using a combination of LOw Frequency ARray (LOFAR; 30-85 and 115-178 MHz), Very Large Array (VLA; 290-420 ...
    • 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 - II. First data release 

      Shimwell, T. W.; Tasse, C.; Hardcastle, M. J.; Mechev, A. P.; Williams, W. L.; Best, P. N.; Röttgering, H. J. A.; Callingham, J. R.; Dijkema, T. J.; Gasperin, F. de; Hoang, D. N.; Hugo, B.; Mirmont, M.; Oonk, J. B. R.; Prandoni, I.; Rafferty, D.; Sabater, J.; Smirnov, O.; Weeren, R. J. van; White, G. J.; Atemkeng, M.; Bester, L.; Bonnassieux, E.; Brüggen, M.; Brunetti, G.; Chyży, K. T.; Cochrane, R.; Conway, J. E.; Croston, J. H.; Danezi, A.; Duncan, K.; Haverkorn, M.; Heald, G. H.; Iacobelli, M.; Intema, H. T.; Jackson, N.; Jamrozy, M.; Jarvis, M. J.; Lakhoo, R.; Mevius, M.; Miley, G. K.; Morabito, L.; Morganti, R.; Nisbet, D.; Orrú, E.; Smith, D. J. B.; Harwood, J. J.; Heesen, V.; Mahatma, V.; Mingo, B. (2018-09-12)
      The LOFAR Two-metre Sky Survey (LoTSS) is an ongoing sensitive, high-resolution 120-168MHz survey of the entire northern sky for which observations are now 20% complete. We present our first full-quality public data release. ...
    • 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 view of FR0 radio galaxies 

      Capetti, A.; Brienza, M.; Baldi, R. D.; Giovannini, G.; Morganti, R.; Hardcastle, M. J.; Rottgering, H. J. A.; Brunetti, G. F.; Best, P. N.; Miley, G. (2020-10-09)
      We explore the low-frequency radio properties of the sources in the Fanaroff-Riley class 0 catalog (FR0CAT) as seen by the LOw Frequency ARray (LOFAR) observations at 150 MHz. This sample includes 104 compact radio active ...
    • 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 ...
    • 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 ...
    • Molecular gas and star formation in local early-type galaxies 

      Bureau, M.; Davis, T.A.; Cappellari, M.; Davies, R.L.; Scott, N.; Alatalo, K.; Blitz, L.; Crocker, A.F.; Young, L.M.; Combes, F.; Bois, M.; Emsellem, E.; Lablanche, P.-Y.; Bournaud, F.; De Zeeuw, P.T.; Krajnović, D.; Kuntschner, H.; Duc, P.-A.; Khochfar, S.; McDermid, R.M.; Morganti, R.; Oosterloo, T.; Serra, P.; Naab, T.; Sarzi, M.; Weijmans, A. (2010-12-01)
      The molecular gas content of local early-type galaxies is constrained and discussed in relation to their evolution. First, as part of the ATLAS survey, we present the first complete, large (260 objects), volume-limited ...
    • The nature of the jet-driven outflow in the radio galaxy 3C305 

      Hardcastle, M.J.; Massaro, F.; Harris, D.E.; O'Dea, C.P.; Siemiginowska, A.; Baum, S.A.; Bianchi, S.; Chiaberge, M.; Morganti, R. (2012-08-11)
      We present Chandra X-ray and Very Large Array radio observations of the radio galaxy 3C305. The X-ray observations reveal the details of the previously known extended X-ray halo around the radio galaxy. We show using X-ray ...
    • Neutral hydrogen in nearby elliptical and lenticular galaxies: the continuing formation of early-type galaxies 

      Morganti, R.; de Zeeuw, P.T.; Oosterloo, T.; McDermid, R.M.; Krajnovic, D.; Cappellari, M.; Kenn, F.; Weijmans, A.; Sarzi, M. (2006)
    • 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 ...
    • Radiative age mapping of the remnant radio galaxy B2 0924+30 : The LOFAR perspective 

      Shulevski, A.; Morganti, R.; Harwood, J. J.; Barthel, P. D.; Jamrozy, M.; Brienza, M.; Brunetti, G.; Röttgering, H. J.A.; Murgia, M.; White, G. J.; Croston, J. H.; Brüggen, M. (2017-04-01)
      We have observed the steep spectrum radio source B2 0924+30 using the LOw Frequency ARray (LOFAR) telescope. Hosted by a z = 0.026 elliptical galaxy, it has a relatively large angular size of 12′ (corresponding to 360 kpc ...
    • Radio spectral properties and jet duty cycle in the restarted radio galaxy 3C388 

      Brienza, M.; Morganti, R.; Harwood, J.; Duchet, T.; Rajpurohit, K.; Shulevski, A.; Hardcastle, M. J.; Mahatma, V.; Godfrey, L. E. H.; Prandoni, I.; Shimwell, T. W.; Intema, H. (2020-06-05)
      Context. Restarted radio galaxies represent a unique tool for investigating the duty cycle of the jet activity in active galactic nuclei (AGN). The radio galaxy 3C388 has long been claimed to be a peculiar example of an ...
    • 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 ...
    • Revisiting the Fanaroff-Riley dichotomy and radio-galaxy morphology with the LOFAR Two-Metre Sky Survey (LoTSS) 

      Mingo, B.; Croston, J. H.; Hardcastle, M. J.; Best, P. N.; Duncan, K. J.; Morganti, R.; Rottgering, H. J. A.; Sabater, J.; Shimwell, T. W.; Williams, W. L.; Brienza, M.; Gurkan, G.; Mahatma, V. H.; Morabito, L. K.; Prandoni, I.; Bondi, M.; Ineson, J.; Mooney, S. (2019-09-01)
      The relative positions of the high and low surface brightness regions of radio-loud active galaxies in the 3CR sample were found by Fanaroff and Riley to be correlated with their luminosity. We revisit this canonical ...