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Now showing items 13032-13051 of 24149

    • The LOFAR Two-metre Sky Survey IV. First Data Release: Photometric redshifts and rest-frame magnitudes 

      Duncan, Kenneth J; Sabater, J.; Röttgering, H. J. A.; Jarvis, M. J.; Smith, D. J. B.; Best, P. N.; Callingham, J. R.; Cochrane, R.; Croston, J. H.; Hardcastle, M. J.; Mingo, B.; Morabito, L.; Nisbet, D.; Prandoni, I.; Shimwell, T. W.; Tasse, C.; White, G. J.; Williams, W. L.; Alegre, L.; Chyży, K. T.; Gürkan, G.; Hoeft, M.; Kondapally, R.; Mechev, A. P.; Miley, G. K.; Schwarz, D. J.; Weeren, R. J. van (2018-11-19)
      The LOFAR Two-metre Sky Survey (LoTSS) is a sensitive, high-resolution 120-168 MHz survey of the Northern sky. The LoTSS First Data Release (DR1) presents 424 square degrees of radio continuum observations over the HETDEX ...

    • The LOFAR Two-metre Sky Survey: Deep Fields: : II. The ELAIS-N1 LOFAR deep field 

      Sabater, J.; Best, P. N.; Tasse, C.; Hardcastle, M. J.; Shimwell, T. W.; Nisbet, D.; Jelic, V.; Callingham, J. R.; Rottgering, H. J. A.; Bonato, M.; Bondi, M.; Ciardi, B.; Cochrane, R. K.; Jarvis, M. J.; Kondapally, R.; Koopmans, L. V. E.; O'Sullivan, S. P.; Prandoni, I.; Schwarz, D. J.; Smith, D. J. B.; Wang, L.; Williams, W. L.; Zaroubi, S. (2021-04-07)
      The LOFAR Two-metre Sky Survey (LoTSS) will cover the full northern sky and, additionally, aims to observe the LoTSS deep fields to a noise level of ~10 microJy/bm over several tens of square degrees in areas that have the ...

    • The LOFAR Two-metre Sky Survey: the radio view of the cosmic star formation history 

      Cochrane, R. K.; Kondapally, R.; Best, P. N.; Sabater, J.; Duncan, K. J.; Smith, D. J. B.; Hardcastle, M. J.; Röttgering, H. J. A.; Prandoni, I.; Haskell, P.; Gürkan, G.; Miley, G. K. (2023-05-26)
      We present a detailed study of the cosmic star formation history over $90$ per cent of cosmic time ($0\lesssim z\lesssim4$), using deep, radio continuum observations that probe star formation activity independent of dust. ...

    • 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 ...

    • 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 ...

    • LOFAR view of NGC 3998, a sputtering AGN 

      Sridhar, Sarrvesh S.; Morganti, Raffaella; Nyland, Kristina; Frank, Bradley S.; Harwood, Jeremy; Oosterloo, Tom (2020-02-18)
      Low-power radio sources dominate the radio sky. They tend to be small in size and dominated by their cores, but the origin of their properties and the evolution of their radio plasma are not well constrained. Interestingly, ...

    • The LOFAR window on star-forming galaxies and AGN - curved radio SEDs and IR-radio correlation at 0 < z < 2.5 

      Rivera, G. Calistro; Williams, W. L.; Hardcastle, M. J.; Duncan, K. J.; Röttgering, H.~J.~A.; Best, Philip N.; Brüggen, Marcus; Chyzy, K.T.; Conselice, C. J.; De Gasperin, Francesco; Engels, D.; Gürkan, G.; Intema, Huib T.; Jarvis, M. J.; Mahony, E. K.; Miley, G.K.; Morabito, L. K.; Prandoni, I.; Sabater, J.; Smith, D. J. B.; Tasse, C.; van der Werf, P.; White, Glenn J. (2017-08-11)
      We present a study of the low-frequency radio properties of star forming (SF) galaxies and active galactic nuclei (AGN) up to redshift $z=2.5$. The new spectral window probed by the Low Frequency Array (LOFAR) allows us ...

    • LOFAR, VLA, and Chandra observations of the Toothbrush galaxy cluster 

      Van Weeren, R. J.; Brunetti, G.; Brüggen, M.; Andrade-Santos, F.; Ogrean, G. A.; Williams, W. L.; Röttgering, H. J. A.; Dawson, W. A.; Forman, W.R.; Gasperin, F. de; Hardcastle, M.J.; Jones, C.; Miley, G.K.; Rafferty, D. A.; Rudnick, L.; Sabater, J.; Sarazin, C.L.; Shimwell, T. W.; Bonafede, A.; Best, P. N.; Bîrzan, L.; Cassano, R.; Chyży, K. T.; Croston, J. H.; Dijkema, T. J.; Ensslin, T.; Ferrari, C.; Heald, G.; Hoeft, M.; Horellou, C.; Jarvis, M.J.; Kraft, R.P.; Mevius, M.; Intema, H. T.; Murray, S. S.; Orrú, E.; Pizzo, R.; Sridhar, S. S.; Simionescu, A.; Stroe, A.; Tol, S. van der; White, G.J. (2016-02-22)
      We present deep LOFAR observations between 120-181 MHz of the "Toothbrush" (RX J0603.3+4214), a cluster that contains one of the brightest radio relic sources known. Our LOFAR observations exploit a new and novel calibration ...

    • LOFAR-Boötes : Properties of high- and low-excitation radio galaxies at 0.5 < z < 2.0 

      Williams, W. L.; Rivera, G. Calistro; Best, Philip N.; Hardcastle, M. J.; Röttgering, H.~J.~A.; Duncan, K. J.; De Gasperin, Francesco; Jarvis, M. J.; Miley, G.K.; Mahony, E. K.; Morabito, L. K.; Nisbet, D. M.; Prandoni, I.; Smith, D. J. B.; Tasse, C.; White, Glenn J. (2018-04-11)
      This paper presents a study of the redshift evolution of radio-loud active galactic nuclei (AGN) as a function of the properties of their galaxy hosts in the Boötes field. To achieve this we match low-frequency radio sources ...

    • A LOFAR-IRAS cross-match study : the far-infrared radio correlation and the 150-MHz luminosity as a star-formation rate 

      Wang, L.; Gao, F.; Duncan, K. J.; Williams, W. L.; Rowan-Robinson, M.; Sabater, J.; Shimwell, T. W.; Bonato, M.; Calistro-Rivera, G.; Chyzy, K. T.; Farrah, D.; Gurkan Uygun, Gulay; Hardcastle, M. J.; McCheyne, I.; Prandoni, I.; Read, S. C.; Rottgering, H. J. A.; Smith, D. J. B. (2019-11-01)
      Aims. We aim to study the far-infrared radio correlation (FIRC) at 150 MHz in the local Universe (at a median redshift z~0:05) and improve the use of the rest-frame 150-MHz luminosity, L150, as a star-formation rate (SFR) ...

    • 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 ...

    • LOFAR/H-ATLAS: The low-frequency radio luminosity - star-formation rate relation 

      Gurkan, Gulay; Hardcastle, Martin J.; Smith, Daniel; Best, Philip N.; Bourne, Nathan; Calistro-Rivera, Gabriela; Heald, George; Jarvis, Matt J.; Prandoni, Isabella; Rottgering, Huub J. A.; Sabater, Jose; Shimwell, Tim; Tasse, Cyril; Williams, Wendy L. (2018-04-11)
      Radio emission is a key indicator of star-formation activity in galaxies, but the radio luminosity-star formation relation has to date been studied almost exclusively at frequencies of 1.4 GHz or above. At lower radio ...

    • Logarithmic simulated annealing for computer-assisted x-ray diagnosis 

      Albrecht, A.; Steinhofel, K.; Taupitz, M.; Wong, C.K. (2001)
      We present a new stochastic learning algorithm and first results of computational experiments on fragments of liver CT images. The algorithm is designed to compute a depth-three threshold circuit, where the first layer is ...

    • Logged labour: : a new paradigm of work organisation? 

      Huws, Ursula (2016-05-30)
      This essay argues that, during the period following the financial crisis of 2007-8, several different trends, already visible in earlier periods, have converged to create a new pattern of work organisation, a pattern which ...

    • Logic in Action: Wittgenstein's Logical Pragmatism and the Impotence of Scepticism 

      Moyal-Sharrock, Daniele (2003)

    • The logic of 'being informed' revisited and revised 

      Allo, P. (2011)
      The logic of 'being informed' gives a formal analysis of a cognitive state that does not coincide with either belief, or knowledge. To Floridi, who first proposed the formal analysis, the latter is supported by the fact ...

    • The logic of being informed 

      Floridi, L. (2006)
      One of the open problems in the philosophy of information is whether there is an information logic (IL), different from epistemic (EL) and doxastic logic (DL), which formalises the relation a is informed--that p (Iap) ...

    • Logica e Pensiero Visivo 

      Floridi, L. (1999)

    • Logical fallacies as informational shortcuts 

      Floridi, L. (2009)
      The paper argues that the two best known formal logical fallacies, namely denying the antecedent (DA) and affirming the consequent (AC) are not just basic and simple errors, which prove human irrationality, but rather ...

    • Logical inconsistency in construct relationships : Conflict or complexity? 

      Winter, David (1983)
      The study examines repertory grid measures of conflict. Evidence is provided that neurotic disorder is associated with high levels of logical consistency in construct relationships, particularly in those concerning ‘symptom ...