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Now showing items 1-16 of 16

    • 10 kpc Scale Seyfert Galaxy Outflow: HST/COS Observations of IRAS F22456-5125 

      Borguet, Benoit C. J.; Edmonds, Douglas; Arav, Nahum; Dunn, Jay; Kriss, Gerard A. (IOP Publishing Ltd., 2012-06)
      We present analysis of the UV spectrum of the low-z AGN IRAS F22456-5125 obtained with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. The spectrum reveals six main kinematic components, spanning a ...
    • Far-infrared fine-structure line diagnostics of ultraluminous infrared galaxies 

      Farrah, D.; Lebouteiller, V.; Spoon, H. W. W.; Bernard-Salas, J.; Pearson, C.; Rigopoulou, D.; Smith, H. A.; Gonzalez-Alfonso, E.; Clements, D. L.; Efstathiou, A.; Cormier, D.; Afonso, J.; Petty, S. M.; Harris, K.; Hurley, P.; Borys, C.; Verma, A.; Cooray, A.; Salvatelli, V. (IOP Publishing Ltd., 2013-10)
      We present Herschel observations of 6 fine-structure lines in 25 ultraluminous infrared galaxies at z < 0.27. The lines, [O III]52 mu m, [N III] 57 mu m, [O I]63 mu m, [N II]122 mu m, [O I]145 mu m, and [C II]158 mu m, are ...
    • Ionization-driven Fragmentation of Gas Outflows Responsible for FeLoBALs in Quasars 

      Bautista, M. A.; Dunn, J. P. (IOP PUBLISHING LTD, 2010-07)
      We show that time variations in the UV ionizing continuum of quasars, on scales of similar to 1 yr, affect the dynamic structure of the plasmas responsible for low-ionization broad absorption lines. Variations of the ...
    • Mid- to far-infrared properties of star-forming galaxies and active galactic nuclei 

      Magdis, G. E.; Rigopoulou, D.; Helou, G.; Farrah, D.; Hurley, P.; Alonso-Herrero, A.; Bock, J.; Burgarella, D.; Chapman, S.; Charmandaris, V.; Cooray, A.; Dai, Y. S.; Dale, D.; Elbaz, D.; Feltre, A.; Hatziminaoglou, E.; Huang, J. S.; Morrison, G.; Oliver, S.; Page, M.; Scott, D.; Shi, Y. (EDP SCIENCES, 2013-10)
      We study the mid- to far-IR properties of a 24 mu m-selected flux-limited sample (S-24 > 5mJy) of 154 intermediate redshift (< z > similar to 0.15), infrared luminous galaxies, drawn from the 5 Milli-Jansky Unbiased Spitzer ...
    • Multiwavelength campaign on Mrk 509 I. Variability and spectral energy distribution 

      Kaastra, J. S.; Petrucci, P. O.; Cappi, M.; Arav, Nahum; Behar, E.; Bianchi, S.; Bloom, J.; Blustin, A. J.; Branduardi-Raymont, G.; Costantini, E.; Dadina, M.; Detmers, R. G.; Ebrero, J.; Jonker, P. G.; Klein, C.; Kriss, G. A.; Lubinski, P.; Malzac, J.; Mehdipour, M.; Paltani, S.; Pinto, C.; Ponti, G.; Ratti, E. M.; Smith, R. A. N.; Steenbrugge, K. C.; de Vries, C. P. (EDP Sciences, 2011-10)
      Context. Active galactic nuclei (AGN) show a wealth of interesting physical processes, some of which are poorly understood. In a broader context, they play an important role in processes that are far beyond their immediate ...
    • Multiwavelength campaign on Mrk 509 III. The 600 ks RGS spectrum: unravelling the inner region of an AGN 

      Detmers, R.G.; Kaastra, J. S.; Steenbrugge, K. C.; Ebrero, J.; Kriss, G. A.; Arav, Nahum; Behar, E.; Costantini, E.; Branduardi-Raymont, G.; Mehdipour, M.; Bianchi, S.; Cappi, M.; Petrucci, P.; Ponti, G.; Pinto, C.; Ratti, E. M.; Holczer, T. (EDP Sciences, 2011-10)
      We present the results of our 600 ks RGS observation as part of the multiwavelength campaign on Mrk 509. The very high quality of the spectrum allows us to investigate the ionized outflow with an unprecedented accuracy due ...
    • Multiwavelength campaign on Mrk 509 V. Chandra-LETGS observation of the ionized absorber 

      Ebrero, J.; Kriss, G. A.; Kaastra, J. S.; Detmers, R. G.; Steenbrugge, K. C.; Costantini, E.; Arav, Nahum; Bianchi, S.; Cappi, M.; Branduardi-Raymont, G.; Mehdipour, M.; Petrucci, P. O.; Pinto, C.; Ponti, G. (EDP Sciences, 2011-10)
      Context. We present here the results of a 180 ks Chandra-LETGS observation as part of a large multi-wavelength campaign on Mrk 509. Aims. We study the warm absorber in Mrk 509 and use the data from a simultaneous HST-COS ...
    • Multiwavelength campaign on Mrk 509 VI. HST/COS observations of the far-ultraviolet spectrum 

      Kriss, G. A.; Arav, Nahum; Kaastra, J. S.; Ebrero, J.; Pinto, C.; Borguet, B.; Edmonds, Douglas; Costantini, E.; Steenbrugge, K. C.; Detmers, R. G.; Behar, E.; Bianchi, S.; Blustin, A. J.; Branduardi-Raymont, G.; Cappi, M.; Mehdipour, M.; Petrucci, P.; Ponti, G. (EDP Sciences, 2011-10)
      We present medium-resolution (lambda/Delta lambda similar to 20 000) ultraviolet spectra covering the 1155-1760 angstrom spectral range of the Seyfert 1 galaxy Mrk 509 obtained using the Cosmic Origins Spectrograph (COS) ...
    • Multiwavelength campaign on Mrk 509 VII. Relative abundances of the warm absorber 

      Steenbrugge, K. C.; Kaastra, J. S.; Detmers, R. G.; Ebrero, J.; Ponti, G.; Costantini, E.; Kriss, G. A.; Mehdipour, M.; Pinto, C.; Branduardi-Raymont, G.; Behar, E.; Arav, Nahum; Cappi, M.; Bianchi, S.; Petrucci, P. O.; Ratti, E. M.; Holczer, T. (EDP Sciences, 2011-10)
      Context. The study of abundances in the nucleus of active galaxies allows us to investigate the evolution of the abundance by comparing local and higher redshift galaxies. However, the methods used so far have substantial ...
    • Multiwavelength campaign on Mrk 509 VIII. Location of the X-ray absorber 

      Kaastra, J. S.; Detmers R. G.; Mehdipour, M.; Arav, Nahum; Behar, E.; Bianchi, S.; Branduardi-Raymont, G.; Cappi, M.; Costantini, E.; Ebrero, J.; Kriss, G. A.; Paltani, S.; Petrucci, P. O.; Pinto, C.; Ponti, G.; Steenbrugge, K. C.; de Vries, C. P. (EDP Sciences, 2012-03)
      Aims. More than half of all active galactic nuclei show strong photoionised outflows. A major uncertainty in models for these outflows is the distance of the gas to the central black hole. We use the results of a massive ...
    • Radial velocity offsets due to mass outflows and extinction in active galactic nuclei 

      Crenshaw, D. M.; Schmitt, H. R.; Kraemer, S. B.; Mushotzky, R. F.; Dunn, J. P. (IOP Publishing Ltd., 2010-01)
      We present a study of the radial velocity offsets between narrow emission lines and host galaxy lines (stellar absorption and Hi 21 cm emission) in Seyfert galaxies with observed redshifts less than 0.043. We find that 35% ...
    • Space Telescope and Optical Reverberation Mapping Project. X. Understanding the Absorption-line Holiday in NGC 5548 

      Dehghanian, M.; Ferland, G. J.; Kriss, G. A.; Peterson, B. M.; Mathur, S.; Mehdipour, M.; Guzman, F.; Chatzikos, M.; van Hoof, P. A. M.; Williams, R. J. R.; Arav, Nahum; Barth, A. J.; Bentz, M. C.; Bisogni, S.; Brandt, W. N.; Crenshaw, D. M.; Dalla Bonta, E.; De Rosa, G.; Fausnaugh, M. M.; Gelbord, J. M.; Goad, M. R.; Gupta, A.; Horne, Keith; Kaastra, J.; Knigge, C.; Korista, K. T.; McHardy, I. M.; Pogge, R. W.; Starkey, D. A.; Vestergaard, M. (2019-06-01)
      The Space Telescope and Optical Reverberation Mapping Project (AGN STORM) on NGC 5548 in 2014 is one of the most intensive multiwavelength AGN monitoring campaigns ever. For most of the campaign, the emission-line variations ...
    • Ultraviolet and X-ray Variability of the Seyfert 1.5 Galaxy Markarian 817 

      Winter, L. M.; Danforth, C.; Vasudevan, R.; Brandt, W. N.; Scott, J.; Froning, C.; Keeney, B.; Shull, J. M.; Penton, S.; Mushotzky, R.; Schneider, D. P.; Arav, Nahum (IOP PUBLISHING LTD, 2011-02)
      We present an investigation of the ultraviolet and X-ray spectra of the Seyfert 1.5 galaxy Markarian 817. The ultraviolet analysis includes two recent observations taken with the Cosmic Origins Spectrograph (COS) in 2009 ...
    • Weak hard X-ray emission from two broad absorption line quasars observed with NuSTAR: Compton-thick absorption or intrinsic X-ray weakness? 

      Luo, B.; Brandt, W. N.; Alexander, D. M.; Harrison, F. A.; Stern, D.; Bauer, F. E.; Boggs, S. E.; Christensen, F. E.; Comastri, A.; Craig, W. W.; Fabian, A. C.; Farrah, D.; Fiore, F.; Fuerst, F.; Grefenstette, B. W.; Hailey, C. J.; Hickox, R.; Madsen, K. K.; Matt, G.; Ogle, P.; Risaliti, G.; Saez, C.; Teng, S. H.; Walton, D. J.; Zhang, W. W. (IOP Publishing Ltd., 2013-08)
      We present Nuclear Spectroscopic Telescope Array (NuSTAR) hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray ...
    • WISE detections of known QSOs at redshifts greater than six 

      Blain, A. W.; Assef, R.; Stern, D.; Tsai, C. W.; Eisenhardt, P.; Bridge, C.; Benford, D.; Jarrett, T.; Cutri, R.; Petty, S.; Wu, J. W.; Wright, E. L. (IOP Publishing Ltd., 2013-12)
      We present WISE All-Sky mid-infrared (IR) survey detections of 55% (17/31) of the known QSOs at z > 6 from a range of surveys: the SDSS, the CFHT-LS, FIRST, Spitzer, and UKIDSS. The WISE catalog thus provides a substantial ...
    • X-ray absorption analysis of MCG-6-30-15: Discerning three kinematic systems 

      Holczer, T.; Behar, E.; Arav, Nahum (IOP Publishing Ltd., 2010-01)
      By analyzing the X-ray spectrum of MCG -6-30-15 obtained with the High Energy Transmission Grating (HETGS) spectrometer on board the Chandra observatory, we identify three kinematically distinct absorption systems; two ...