Browsing by Title

Now showing items 18340-18359 of 24473

    • Radio jets and galaxies as cosmic string probes 

      Feng, Fabo (2012-08-01)

    • Radio jets in NGC 4151 where eMERLIN meets HST 

      Williams, D. R. A.; McHardy, I. M.; Baldi, R. D.; Beswick, R. J.; Argo, M. K.; Dullo, B. T.; Knapen, J. H.; Brinks, E.; Fenech, D. M.; Mundell, C.G.; Muxlow, T.W.B.; Panessa, F.; Rampadarath, H.; Westcott, J. (2017-12-21)
      We present high-sensitivity eMERLIN radio images of the Seyfert galaxy NGC 4151 at 1.5 GHz. We compare the new eMERLIN images to those from archival MERLIN observations in 1993 to determine the change in jet morphology in ...

    • Radio Measurements of the stellar proper motions in the core of the Orion Nebula Cluster 

      Dzib, Sergio A.; Loinard, Laurent; Rodríguez, Luis F.; Gómez, Laura; Forbrich, Jan; Menten, Karl M.; Kounkel, Marina A.; Mioduszewski, Amy J.; Hartmann, Lee; Tobin, John J.; Rivera, Juana L. (2017-01-10)
      Using multi-epoch VLA observations, covering a time baseline of 29.1 years, we have measured the proper motions of 88 young stars with compact radio emission in the core of the Orion Nebula Cluster (ONC) and the neighboring ...

    • Radio monitoring of the periodically variable IR source LRLL 54361: No direct correlation between the radio and IR emissions 

      Forbrich, Jan; Rodríguez, Luis F.; Palau, Aina; Zapata, Luis A.; Muzerolle, James; Gutermuth, Robert A. (2015-11-12)
      LRLL 54361 is an infrared source located in the star forming region IC 348 SW. Remarkably, its infrared luminosity increases by a factor of 10 during roughly one week every 25.34 days. To understand the origin of these ...

    • Radio source-component association for the LOFAR Two-metre Sky Survey with region-based convolutional neural networks 

      Mostert, Rafaël I. J.; Duncan, Kenneth J.; Alegre, Lara; Röttgering, Huub J. A.; Williams, Wendy L.; Best, Philip N.; Hardcastle, Martin J.; Morganti, Raffaella (2022-12-01)
      Radio loud active galactic nuclei (RLAGNs) are often morphologically complex objects that can consist of multiple, spatially separated, components. Astronomers often rely on visual inspection to resolve radio component ...

    • Radio spectra of bright compact sources at z>4.5 

      Coppejans, Rocco; Velzen, Sjoert van; Intema, Huib T.; Müller, Cornelia; Frey, Sándor; Coppejans, Deanne L.; Cseh, Dávid; Williams, Wendy; Falcke, Heino; Körding, Elmar G.; Orrú, Emanuela; Paragi, Zsolt; Gabányi, Krisztina É. (2017-05-01)
      High-redshift quasars are important to study galaxy and active galactic nuclei (AGN) evolution, test cosmological models, and study supermassive black hole growth. Optical searches for high-redshift sources have been very ...

    • The radio spectral energy distribution of infrared-faint radio sources 

      Herzog, A.; Norris, R. P.; Middelberg, E.; Seymour, N.; Spitler, L. R.; Emonts, B. H. C.; Franzen, T. M. O.; Hunstead, R.; Intema, H. T.; Marvil, J.; Parker, Q. A.; Sirothia, S. K.; Hurley-Walker, N.; Bell, M.; Bernardi, G.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Callingham, J. R.; Deshpande, A. A.; Dwarakanath, K. S.; For, B. -Q.; Greenhill, L. J.; Hancock, P.; Hazelton, B. J.; Hindson, L.; Johnston-Hollitt, M.; Kapinska, A. D.; Kaplan, D. L.; Lenc, E.; Lonsdale, C. J.; McKinley, B.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Morgan, J.; Oberoi, D.; Offringa, A.; Ord, S. M.; Prabu, T.; Procopio, P.; Shankar, N. Udaya; Srivani, K. S.; Staveley-Smith, L.; Subrahmanyan, R.; Tingay, S. J.; Wayth, R. B.; Webster, R. L.; Williams, A.; Williams, C. L.; Wu, C.; Zheng, Q.; Chippendale, A. P.; Harvey-Smith, L.; Heywood, I.; Indermuehle, B.; Popping, A.; Sault, R. J.; Whiting, M. T. (2016-09-01)
      Infrared-faint radio sources (IFRS) are a class of radio-loud (RL) active galactic nuclei (AGN) at high redshifts (z > 1.7) that are characterised by their relative infrared faintness, resulting in enormous radio-to-infrared ...

    • 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 ...

    • Radio Surveys of Star Formation in the Milky Way with the Next Generation of Interferometers 

      Mutale, Mubela (2023-02-03)
      This thesis embodies work that contributes towards building our knowledge on the birth of massive stars. It presents three projects that study young HII regions which, being a direct product of the birth of massive stars, ...

    • Radio through X-ray spectral energy distributions of 38 broad absorption line quasars 

      Gallagher, S.C.; Hines, D.C.; Blaylock, M.; Priddey, R.; Brandt, W.N.; Egami, E. (2007)

    • A radio through x-ray study of the hot spots, active nucleus and environment of the nearby FR II radio galaxy 3C 33 

      Kraft, R.P.; Birkinshaw, M.; Hardcastle, M.J.; Evans, D.A.; Croston, J.H.; Worrall, D.M.; Murray, S.S. (2007)

    • A Radio through X-Ray Study of the Jet/Companion-Galaxy Interaction in 3C 321 

      Evans, D.A.; Fong, W-F.; Hardcastle, M.J.; Kraft, R.P.; Lee, J.C.; Worrall, D.M.; Birkinshaw, M.; Croston, J.H.; Muxlow, T.W.B. (2008)

    • Radio, optical and X-ray nuclei in nearby 3CRR radio galaxies 

      Hardcastle, M.J.; Worrall, D.M. (2000)
      HST observations have shown that low-redshift 3CR radio galaxies often exhibit a point-like optical component positionally coincident with the GHz-frequency radio core. In this paper we discuss the correlation between the ...

    • Radio-AGN Feedback : When the Little Ones were Monsters 

      Williams, W. L.; Röttgering, H. J. A. (2015-06-21)
      We present a study of the evolution of the fraction of radio-loud active galactic nuclei (AGN) as a function of their host stellar mass. We make use of two samples of radio galaxies: one in the local universe, $0.01 10^{24}$ ...

    • Radio-Loud Active Galactic Nucleus : is there a link between luminosity and cluster environment? 

      Ineson, J.; Croston, J.H.; Hardcastle, M.J.; Kraft, R.P.; Evans, D. A.; Jarvis, M.J. (2013-06-20)
      We present here the first results from the Chandra ERA (Environments of Radio-loud AGN) Large Project, characterizing the cluster environments of a sample of 26 radio-loud active galactic nuclei (AGNs) at z similar to 0.5 ...

    • 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 ...

    • A radio-optical study of blue compact dwarf galaxies. I. : Radio continuum observations 

      Klein, U.; Weiland, H.; Brinks, E. (1991-06-01)

    • Radio-quiet quasars in the VIDEO survey : evidence for AGN-powered radio emission at S-1.4 GHz<1 mJy 

      White, S. V.; Jarvis, M.J.; Haussler, B.; Maddox, N. (2015-04-11)
      Understanding the interplay between black-hole accretion and star formation, and how to disentangle the two, is crucial to our understanding of galaxy formation and evolution. To investigate, we use a combination of optical ...

    • The Radioactive Nuclei 26Al and 60Fe in the Cosmos and in the Solar System 

      Diehl, Roland; Lugaro, Maria; Heger, Alexander; Sieverding, Andre; Tang, Xiaodong; Li, KuoAng; Li, Ertao; Doherty, Carolyn L.; Krause, Martin G. H.; Wallner, Anton; Prantzos, Nikos; Brinkman, Hannah E.; Hartogh, Jaqueline W. den; Wehmeyer, Benjamin; López, Andre Yagüe; Pleintinger, Moritz M. M.; Banerjee, Projival; Wang, Wei (2021-12-09)
      The cosmic evolution of the chemical elements from the Big Bang to the present time is driven by nuclear fusion reactions inside stars and stellar explosions. A cycle of matter recurrently re-processes metal-enriched stellar ...

    • Radiofrequency-based treatment in therapy-related clinical practice – a narrative review. Part I : acute conditions 

      Kumaran, Binoy; Watson, Tim (2015-08-01)
      Background: Radiofrequency electromagnetic field (RFEMF or simply RF)-based electrophysical agents (EPAs) have been employed in therapy-related clinical practice for several decades. They are used to reduce pain and ...