Now showing items 1-14 of 14

    • Chandra observations of the radio galaxy 3C 445 and the hot spot x-ray emission mechanism 

      Perlman, Eric S.; Georganopoulos, Markos; May, Emily M.; Kazanas, Demosthenes (2010-01-01)
      We present new Chandra observations of the radio galaxy 3C 445, centered on its southern radio hot spot. Our observations detect X-ray emission displaced upstream and to the west of the radio–optical hot spot. Attempting ...
    • Chandra observations of the radio galaxy 3C 445 and the hot spot X-ray emission mechanism 

      Perlman, Eric S.; Georganopoulos, Markos; May, Emily M.; Kazanas, Demosthenes (2010-01)
      We present new Chandra observations of the radio galaxy 3C 445, centered on its southern radio hot spot. Our observations detect X-ray emission displaced upstream and to the west of the radio-optical hot spot. Attempting ...
    • Deep multiwaveband observations of the jets of 0208-512 and 1202-262 

      Perlman, Eric S.; Georganopoulos, Markos; Marshall, Herman L.; Schwartz, Daniel A.; Padgett, Charles A.; Gelbord, Jonathan M.; Lovell, James E. J.; Worrall, Diana M.; Birkinshaw, Mark; Murphey, David W. (2011-09-07)
      We present deep Hubble Space Telescope, Chandra, Very Large Array, and Australia Telescope Compact Array images of the jets of PKS 0208-512 and PKS 1202-262, which were found in a Chandra survey of a flux-limited sample ...
    • An HST proper-motion study of the large scale jet of 3C273 

      Meyer, Eileen T.; Sparks, William B.; Georganopoulos, Markos; Anderson, Jay; van der Marel, Roeland; Biretta, John; Sohn, Sangmo Tony; Chiaberge, Marco; Perlman, Eric; Norman, Colin (2016-02-20)
      The radio galaxy 3C 273 hosts one of the nearest and best-studied powerful quasar jets. Having been imaged repeatedly by the Hubble Space Telescope (HST) over the past twenty years, it was chosen for an HST program to ...
    • Hubble space telescope observations of the quasar PKS 0637-752: Equipartition electron-proton jet from the most complete spectral coverage to date 

      Mehta, Kushal T.; Georganopoulos, Markos; Perlman, Eric S.; Padgett, Charles A.; Chartas, George (2009-01-10)
      We present new Near-Infrared Camera and Multi-Object Spectrometer and attitude control system observations of the quasar jet PKS 0637-752, and we use them, together with existing multiwavelength observations, to produce ...
    • A method for localizing energy dissipation in blazars using Fermi variability 

      Dotson, Amanda; Georganopoulos, Markos; Kazanas, Demosthenes; Perlman, Eric S. (2012-10-10)
      The distance of a Fermi-detected blazar γ-ray emission site from a supermassive black hole is a matter of active debate. Here we present a method for testing if the GeV emission of powerful blazars is produced within the ...
    • A multi-wavelength spectral and polarimetric study of the jet of 3C 264 

      Perlman, Eric S.; Padgett, Charles A.; Georganopoulos, Markos; Worrall, Diana M.; Kastner, Joel H.; Franz, Geoffrey A.; Birkinshaw, Mark; Dulwich, Fred; O'Dea, Christopher P.; Baum, Stefi (2010-01)
      We present a comprehensive multi-band spectral and polarimetric study of the jet of 3C 264 (NGC 3862). Included in this study are three Hubble Space Telescope (HST) optical and ultraviolet polarimetry data sets, along with ...
    • A multi-wavelength study of the jet, lobes, and core of the quasar PKS 2101-490 

      Perlman, Eric S.; Godfrey, Leith E. H.; Lovell, James E. J.; Jauncey, David L.; Schwartz, Daniel A.; Marshall, Herman L.; Birkinshaw, Mark; Worrall, Diana M.; Georganopoulos, Markos; Murphey, David W. (2012-08-07)
      We present a detailed study of the x-ray, optical, and radio emission from the jet, lobes, and core of the quasar PKS 2101−490 as revealed by new Chandra, Hubble Space Telescope (HST), and ATCA images. We extract the radio ...
    • A multizone model for simulating the high-energy variability of TeV blazars 

      Graff, Philip B.; Georganopoulos, Markos; Perlman, Eric S.; Kazanas, Demosthenes (2008-12-10)
      We present a time-dependent multizone code for simulating the variability of synchrotron self-Compton (SSC) sources. The code adopts a multizone pipe geometry for the emission region, appropriate for simulating emission from ...
    • A Novel Method for Measuring the Extragalactic Background Light: Fermi Application to the Lobes of Fornax A 

      Georganopoulos, Markos; Sambruna, Rita M.; Kazanas, Demosthenes; Cillis, Analia N.; Cheung, Chi C.; Perlman, Eric S.; Blundell, Katherine M.; Davis, David S. (2008-10-10)
      We describe a new method for measuring the extragalactic background light (EBL) through the detection of γ-ray inverse Compton (IC) emission due to scattering of the EBL photons off relativistic electrons in the lobes of ...
    • Optical polarization and spectral variability in the M87 jet 

      Perlman, Eric S.; Cara, Mihai; Bourque, Matthew; Simons, Raymond C.; Adams, Steven C.; Harris, Daniel E.; Madrid, Juan P.; Clausen-Brown, Eric; Cheung, Chi C.; Georganopoulos, Markos (2011-11-29)
      During the last decade, M87's jet has been the site of an extraordinary variability event, with one knot (HST-1) increasing by over a factor 100 in brightness. Variability has also been seen on timescales of months in the ...
    • Polarimetry and the high-energy emission mechanisms in quasar jets: the case of PKS 1136-135 

      Cara, Mihai; Perlman, Eric S.; Uchiyama, Yasunobu; Cheung, Chi C.; Coppi, Paolo S.; Georganopoulos, Markos; Worrall, Diana M.; Birkinshaw, Mark; Sparks, William B.; Marshall, Herman L. (2013-08-20)
      Since the discovery of kiloparsec-scale X-ray emission from quasar jets, the physical processes responsible for their high-energy emission have been poorly defined. A number of mechanisms are under active debate, including ...
    • The puzzling case of the radio-loud QSO 3C 186: A gravitational wave recoiling black hole in a young radio source? 

      Chiaberge, Marco; Ely, Justin C.; Meyer, Eileen T.; Georganopoulos, Markos; Marinucci, Andrea; Bianchi, Stefano; Tremblay, Grant R; Hilbert, Bryan; Kotyla, J.P.; Perlman, Eric S (2017-03-30)
      Context. Radio-loud active galactic nuclei with powerful relativistic jets are thought to be associated with rapidly spinning black holes (BHs). BH spin-up may result from a number of processes, including accretion of ...
    • Ruling out IC/CMB X-rays in PKS 0637-752 and the implications for TEV emission from large-scale quasar jets 

      Perlman, Eric S.; Meyer, Eileen T.; Georganopoulos, Markos; Sparks, William B.; Godfrey, Leith E H; Lovell, James E J (2015-06-01)
      The Chandra X-ray observatory has discovered dozens of resolved, kiloparsec-scale jets associated with powerful quasars in which the X-ray fluxes are observed to be much higher than the expected level based on the radio-optical ...