Now showing items 1-9 of 9

    • Multiwavelength Observations of Short-Timescale Variability in NGC 4151. IV. Analysis of Multiwavelength Continuum Variability 

      Edelson, R. A.; Alexander, T.; Crenshaw, D. M.; Kaspi, S.; Malkan, M. A.; Peterson, B. M.; Warwick, R. S.; Clavel, J.; Filippenko, A. V.; Horne, K.; Korista, K. T.; Kriss, G. A.; Krolik, J. H.; Maoz, D.; Nandra, K.; O, P. T.; Penton, S. V.; Yaqoob, T.; Albrecht, P.; Alloin, D.; Ayres, T. R.; Balonek, T. J.; Barr, P.; Barth, A. J.; Bertram, R.; Bromage, G. E.; Carini, M.; Carone, T. E.; Cheng, F.-Z.; Chuvaev, K. K.; Dietrich, M.; Dultzin-Hacyan, D.; Gaskell, C. M.; Glass, I. S.; Goad, M. R.; Hemar, S.; Ho, L. C.; Huchra, J; Hutchings, J.; Johnson, W. N.; Kazanas, D.; Kollatschny, W.; Koratkar, A. P.; Kovo, O.; Laor, A.; MacAlpine, G. M.; Magdziarz, P.; Martin, P. G.; Matheson, T.; McCollum, B.; Miller, H. R.; Morris, S. L.; Oknyanskij, V. L.; Penfold, J.; Perez, E.; Perola, G. C.; Pike, G.; Pogge, R. W.; Ptak, R. L.; Qian, B.-C.; Recondo-Gonzalez, M. C.; Reichert, G. A.; Rodriguez-Espinoza, J. M.; Rodriguez-Pascual, P. M.; Rokaki, E. L.; Roland, J.; Sadun, A. C.; Salamanca, I.; Santos-Lleo, M.; Shields, J. C.; Shull, J. M.; Smith, D. A.; Smith, S. M.; Snijders, M. A. J.; Stirpe, G. M.; Stoner, R. E.; Sun, W.-H.; Ulrich, M.-H.; van Groningen, E.; Wagner, R. M.; Wagner, S.; Wanders, I.; Welsh, W. F.; Weymann, R. J.; Wilkes, Belinda Jane; Wu, H.; Wurster, J.; Xue, S.-J.; Zdziarski, A. A.; Zheng, W.; Zou, Z.-L. (IOP Publishing, 1996)
      This paper combines data from the three preceding papers in order to analyze the multi-wave-band variability and spectral energy distribution of the Seyfert I galaxy NGC 4151 during the 1993 December monitoring campaign. ...
    • Narrow-line AGN in the ISO-2MASS survey 

      Leipski, C.; Haas, M.; Meusinger, H.; Siebenmorgen, R.; Chini, R.; Drass, H.; Albrecht, M.; Wilkes, Belinda Jane; Huchra, J; Ott, S.; Cesarsky, C.; Cutri, R. (EDP Sciences, 2007)
      Context. A long-standing challenge of observational AGN research is to find type 2 quasars, the luminous analogues of Seyfert-2 galaxies. Aims. We search for luminous narrow-line type 2 AGN, characterise their properties, ...
    • Optical Continuum and Emission‐Line Variability of the Seyfert 1 Galaxy Markarian 509 

      Carone, T. E.; Peterson, B. M.; Bechtold, J.; Bertram, R.; Bischoff, K.; Dietrich, M.; Filppenko, A. V.; Ho, L. C.; Huchra, J; Kollatchny, W.; Korista, K. T.; Matheson, T.; Pogge, R. W.; Shields, J. C.; Smith, P. S.; Wagner, R. M.; Wilkes, Belinda Jane (IOP Publishing, 1996)
      We report on the results of a 5 year coordinated program of spectroscopic monitoring of the luminous Seyfert 1 galaxy Markarian 509. The Hβ and He II λ4686 emission lines are found to respond to continuum variations with ...
    • A Spectroscopic and Photometric Study of Short-Timescale Variability in NGC 5548 

      Dietrich, M.; Bender, C.; Bergmann, D.; Bills, T.; Bochkarev, N.; Burenkov, A.; Gaskell, C.; Gutzmer, D.; Grove, R.; Hiller, M.; Huchra, John; Klimek, E.; Lund, C.; Merkulova, N.; Pebley, S.; Poulsen, M.; Pronik, V.; Sergeev, S.; Sergeeva, E.; Shapovalova, A.; Vlasyuk, V.; Wilkes, Belinda (2001)
      Results of a ground-based optical monitoring campaign on NGC 5548 in June 1998 are presented. The broad-band fluxes (U, B, V), and the spectrophotometric optical continuum flux F wavelength (5100 Å) monotonically decreased ...
    • Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. II - an intensive study of NGC 5548 at optical wavelengths 

      Peterson, B. M.; Balonek, T. J.; Barker, E. S.; Bechtold, J.; Bertram, R.; Bochkarev, N. G.; Bolte, M. J.; Bond, D.; Boroson, T. A.; Carini, M. T.; Carone, T. E.; Christensen, J. A.; Clements, S. D.; Cochran, A. L.; Cohen, R. D.; Crampton, D.; Dietrich, M.; Elvis, Martin S.; Ferguson, A.; Filippenko, A. V.; Fricke, K. J.; Gaskell, C. M.; Halpern, J. P.; Huchra, J; Hutchings, J. B.; Kollatschny, W.; Koratkar, A. P.; Korista, K. T.; Krolik, J. H.; Lame, N. J.; Laor, A.; Leacock, R. J.; MacAlpine, G. M.; Malkan, M. A.; Maoz, D.; Miller, H. R.; Morris, S. L.; Netzer, H.; Oliveira, C. L. M.; Penfold, J.; Penston, M. V.; Perez, E.; Pogge, R. W.; Richmond, M. W.; Romanishin, W.; Rosenblatt, E. I.; Saddlemyer, L.; Sadun, A.; Sawyer, S. R.; Shields, J. C.; Shapovalova, A. I.; Smith, A. G.; Smith, H. A.; Smith, P. S.; Sun, W.-H.; Thiele, U.; Turner, T. J.; Veilleux, S.; Wagner, R. M.; Weymann, R. J.; Wilkes, Belinda Jane; Wills, B. J.; Wills, D.; Younger, P. F. (IOP Publishing, 1991)
      A large, international program of ground-based optical spectroscopy and photometry of the variable Seyfert 1 galaxy NGC 5548 undertaken in support of an IUE monitoring campaign is described. This contribution presents the ...
    • Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. III - Further observations of NGC 5548 at optical wavelengths 

      Peterson, B. M.; Alloin, D.; Axon, D.; Balonek, T. J.; Bertram, R.; Boroson, T. A.; Christensen, J. A.; Clements, S. D.; Dietrich, M.; Elvis, Martin S.; Filippenko, A. V.; Gaskell, C. M.; Haswell, C. A.; Huchra, J; Jackson, N.; Kollatschny, W.; Korista, K. T.; Lame, N. J.; Leacock, R. J.; Lin, S.-N.; Malkan, M. A.; Monk, A. S.; Penston, M. V.; Pogge, R. W.; Robinson, A.; Rosenblatt, E. I.; Shields, J. C.; Smith, A. G.; Stirpe, G. M.; Sun, W.-H.; Turner, T. J.; Wagner, R. M.; Wilkes, Belinda Jane; Wills, B. J. (IOP Publishing, 1992)
      The results of the second year of an intensive ground-based spectroscopic and photometric study of variability in the bright Seyfert 1 galaxy NGC 5548 are reported in order to study the relationship between continuum and ...
    • Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. IV - Intensity variations of the optical emission lines of NGC 5548 

      Dietrich, M.; Kollatschny, W.; Peterson, B. M.; Bechtold, J.; Bertram, R.; Bochkarev, N. G.; Boroson, T. A.; Carone, T. E.; Elvis, Martin S.; Filippenko, A. V.; Gaskell, C. M.; Huchra, J; Hutchings, J. B.; Koratkar, A. P.; Korista, K. T.; Lame, N. J.; Laor, A.; MacAlpine, G. M.; Malkan, M. A.; Mendes de Oliveira, C.; Netzer, H.; Penfold, J.; Penston, M. V.; Perez, E.; Pogge, R. W.; Richmond, M. W.; Rosenblatt, E. I.; Shapovalova, A. I.; Shields, J. C.; Smith, H. A.; Smith, P. S.; Sun, W.-H.; Thiele, U.; Veilleux, S.; Wagner, R. M.; Wilkes, Belinda Jane; Wills, B. J.; Wills, D. (IOP Publishing, 1993)
      Measurements of optical emission-line flux variations based on spectra of the Seyfert galaxy NGC 5548 obtained between December 1988 and October 1989 are reported. All of the measured optical emission lines, H-alpha, H-beta, ...
    • Steps toward determination of the size and structure of the broad-line region in active nuclei. 7: Variability of the optical spectrum of NGC 5548 over years 

      Peterson, B. M.; Berlind, Perry; Bertram, R.; Bochkarev, N. G.; Bond, D.; Brotherton, M. S.; Busler, J. R.; Chuvaev, K. K.; Cohen, R. D.; Dietrich, M.; Elvis, Martin S.; Filippenko, A. V.; Foltz, C. B.; Garnavich, P. M.; Ho, L. C.; Horine, E.; Horne, K.; Huchra, J; Kollatschny, W.; Korista, K. T.; Malkan, M. A.; Matheson, T.; Mignoli, M.; Morris, S. L.; Nazarova, L.; Penfold, J.; Peters, J.; Pogge, R. W.; Pronik, V. I.; Rush, B.; Sergeev, S. G.; Shapovalova, A. I.; Shields, J. C.; Stirpe, G. M.; Tokarz, S.; Wagner, Rudolf; Weymann, R. J.; White, R. J.; Wilkes, Belinda Jane; Wills, D.; Wills, B. J.; Winge, C.; Younger, P. F. (IOP Publishing, 1994)
      We report on the results of a continuation of a large monitoring program of optical spectroscopy of the Seyfert 1 galaxy NGC 5548. The new observations presented here were obtained between 1990 December and 1992 October, ...
    • Steps toward Determination of the Size and Structure of the Broad‐Line Region in Active Galactic Nuclei. XV. Long‐Term Optical Monitoring of NGC 5548 

      Peterson, B. M.; Barth, A. J.; Berlind, P.; Bertram, R.; Bischoff, K.; Bochkarev, N. G.; Burenkov, A. N.; Cheng, F.‐Z.; Dietrich, M.; Filippenko, A. V.; Giannuzzo, E.; Ho, L. C.; Huchra, J; Hunley, J.; Kaspi, S.; Kollatschny, W.; Leonard, D. C.; Malkov, Yu. F.; Matheson, T.; Mignoli, M.; Nelson, B.; Papaderos, P.; Peters, J.; Pogge, R. W.; Pronik, V. I.; Sergeev, S. G.; Sergeeva, E. A.; Shapovalova, A. I.; Stirpe, G. M.; Tokarz, S.; Wagner, R. M.; Wanders, I.; Wei, J.‐Y.; Wilkes, Belinda Jane; Wu, H.; Xue, S.‐J.; Zou, Z.‐L. (IOP Publishing, 1999)
      We present the results of 3 yr of ground-based observations of the Seyfert 1 galaxy NGC 5548, which, combined with previously reported data, yield optical continuum and broad-line Hβ light curves for a total of 8 yr. The ...