Now showing items 1-20 of 127

    • 3c 220.3: A Radio Galaxy Lensing a Submillimeter Galaxy 

      Haas, Martin; Leipski, Christian; Barthel, Peter; Wilkes, Belinda Jane; Vegetti, Simona; Bussmann, R. Shane; Willner, Steven P.; Westhues, Christian; Ashby, Matthew L N; Chini, Rolf; Clements, David L.; Fassnacht, Christopher D.; Horesh, Assaf; Klaas, Ulrich; Koopmans, Léon V. E.; Kuraszkiewicz, Joanna; Lagattuta, David J.; Meisenheimer, Klaus; Stern, Daniel; Wylezalek, Dominika (IOP Publishing, 2014)
      Herschel Space Observatory photometry and extensive multiwavelength follow-up have revealed that the powerful radio galaxy (PRG) 3C 220.3 at z = 0.685 acts as a gravitational lens for a background submillimeter galaxy (SMG) ...
    • Absorption in X-ray spectra of high-redshift quasars 

      Elvis, Martin S.; Fiore, Fabrizio; Wilkes, Belinda Jane; McDowell, Jonathan Christopher; Bechtold, Jill (IOP Publishing, 1994)
      We present evidence that X-ray absorption is common in high-redshift quasars. We have studied six high-redshift (z approximately 3) quasars with the ROSAT Position Sensitive Proportional Counter (PSPC) of which four are ...
    • Accurate galactic N(H) values towards quasars and AGN 

      Elvis, Martin; Wilkes, Belinda Jane; Lockman, Felix J. (IOP Publishing, 1989)
      Integrated Galactic 21-cm column densities toward about 174 quasars and AGN are presented. The data are corrected for stray radiation, using the technique of Lockman et al. (1986). Because of the 21-arcmin beam size of the ...
    • Active Galactic Nucleus and Starburst Classification from Spitzer Mid‐Infrared Spectra for High‐Redshift SWIRE Sources 

      Weedman, D.; Polletta, M.; Lonsdale, C. J.; Wilkes, Belinda Jane; Siana, B.; Houck, John; Surace, J.; Shupe, D.; Farrah, D.; Smith, H. E. (IOP Publishing, 2006)
      Spectra have been obtained with the Infrared Spectrograph (IRS) on the Spitzer Space Telescope for 20 sources in the Lockman Hole field of the SWIRE survey. The sample is divided between sources with indicators of an ...
    • ASCA observations of two steep soft X-ray quasars 

      Fiore, F.; Matt, G.; Cappi, M.; Elvis, Martin S.; Leighly, K. M.; Nicastro, F.; Piro, L.; Siemiginowska, Aneta L.; Wilkes, Belinda Jane (Oxford University Press (OUP), 1998)
      Steep soft X-ray (0.1-2 keV) quasars share several unusual properties: narrow Balmer lines, strong FeII emission, large and fast X-ray variability, rather steep 2-10 keV spectrum. These intriguing objects have been suggested ...
    • Atlas of quasar energy distributions 

      Elvis, Martin S.; Wilkes, Belinda Jane; McDowell, Jonathan Christopher; Green, Richard F.; Bechtold, Jill; Willner, Steven P.; Oey, M. S.; Polomski, Elisha; Cutri, Roc (IOP Publishing, 1994)
      We present an atlas of the spectral energy distributions (SEDs) of normal, nonblazar, quasars over the whole available range (radio to 10 keV X-rays) of the electromagnetic spectrum. The primary (UVSX) sample includes 47 ...
    • BeppoSAX Observations of the Maser Seyfert 2 Galaxy ESO 103‐G35 

      Wilkes, Belinda Jane; Mathur, Smita; Fiore, Fabrizio; Antonelli, Angelo; Nicastro, Fabrizio (IOP Publishing, 2001)
    • The BeppoSAX View of the X‐Ray Active Nucleus of NGC 4258 

      Fiore, F.; Pellegrini, S.; Matt, G.; Antonelli, L. A.; Comastri, A.; della Ceca, R.; Giallongo, E.; Mathur, S.; Molendi, S.; Siemiginowska, Aneta L.; Trinchieri, G.; Wilkes, Belinda Jane (IOP Publishing, 2001)
      BeppoSAX observed the Seyfert 1.9 galaxy NGC 4258 in 1998 December, when its 2-10 keV luminosity was about 1041 ergs s-1. Large amplitude (100%) variability is observed in the 3-10 keV band on timescales of a few tens of ...
    • The Cambridge-Cambridge ROSAT Serendipity Survey - III. VLA observations and the evolution of radio-quiet and radio-loud objects 

      Ciliegi, P.; Elvis, Martin S.; Wilkes, Belinda Jane; Boyle, B. J.; McMahon, R. G.; Maccacaro, T. (Oxford University Press (OUP), 1995)
      We present the results of the VLA radio observations at 1.475 GHz (20 cm) of the active galactic nuclei (AGN) in the Cambridge-Cambridge ROSAT Serendipity Survey (CRSS), a sample of 123 faint X-ray sources with ...
    • The Cambridge-Cambridge ROSAT Serendipity Survey -- IV. The X-ray properties 

      Ciliegi, P.; Elvis, Martin S.; Wilkes, Belinda Jane; Boyle, B. J.; McMahon, R. G. (Oxford University Press (OUP), 1997)
      We present a detailed X-ray spectral analysis in the 0.1–2.4 keV ROSAT band of a complete sample of X-ray-selected AGN using the 80 AGNs in the Cambridge-Cambridge ROSAT Serendipity Survey (68 QSOs and 12 narrow-emission-line ...
    • The Cambridge-Cambridge ROSAT Serendipity Survey -- V. Catalogue and optical identifications 

      Boyle, B. J.; Wilkes, Belinda Jane; Elvis, Martin S. (Oxford University Press (OUP), 1997)
      We report the results of a medium-depth X-ray survey of 20 ROSAT Position Sensitive Proportional Counter (PSPC) fields. 123 X-ray sources were detected down to a flux limit of S(0.5–2 keV) > 2 × 10−14 erg s−1 cm−2 lying ...
    • The Cambridge–Cambridge ROSAT Serendipity Survey – II. Classification of X-ray-luminous Galaxies 

      Boyle, B.J.; McMahon, R.G.; Wilkes, Belinda Jane; Elvis, Martin S. (Royal Astronomical Society, 1995)
      We present the results of an intermediate-resolution (1.5\AA) spectroscopic study of 17 X-ray luminous narrow emission-line galaxies previously identified in the Cambridge-Cambridge {\it ROSAT} Serendipity Survey and the ...
    • ChaMP Serendipitous Galaxy Cluster Survey 

      Barkhouse, W. A.; Green, P. J.; Vikhlinin, Alexey A.; Kim, D.‐W.; Perley, D.; Cameron, R.; Silverman, J.; Mossman, A.; Burenin, R.; Jannuzi, B. T.; Kim, M.; Smith, M. G.; Smith, R. C.; Tananbaum, Harvey D.; Wilkes, Belinda Jane (IOP Publishing, 2006)
      We present a survey of serendipitous extended X-ray sources and optical cluster candidates from the Chandra Multiwavelength Project (ChaMP). Our main goal is to make an unbiased comparison of X-ray and optical cluster ...
    • Chandra and Spitzer Unveil Heavily Obscured Quasars in the Chandra /SWIRE Survey 

      Polletta, Maria del Carmen; Wilkes, Belinda Jane; Siana, Brian; Lonsdale, Carol J.; Kilgard, Roy; Smith, Harding E.; Kim, Dong‐Woo; Owen, Frazer; Efstathiou, Andreas; Jarrett, Tom; Stacey, Gordon; Franceschini, Alberto; Rowan‐Robinson, Michael; Babbedge, Tom S. R.; Berta, Stefano; Fang, Fan; Farrah, Duncan; Gonzalez‐Solares, Eduardo; Morrison, Glenn; Surace, Jason A.; Shupe, Dave L. (IOP Publishing, 2006)
      Using the large multiwavelength data set in the Chandra/SWIRE Survey (0.6 deg2 in the Lockman Hole), we show evidence for the existence of highly obscured (Compton-thick) AGNs, estimate a lower limit to their surface ...
    • Chandra Detection of Highest Redshift (z ~ 6) Quasars in X-Rays 

      Mathur, Smita; Wilkes, Belinda Jane; Ghosh, Himel (IOP Publishing, 2002)
      We report on Chandra observations of the three quasars SDSSp J083643+005453, SDSSp J103027+052455, and SDSSp J130608+035626 at redshifts 5.82, 6.28, and 5.99, respectively. All three sources are clearly detected in the ...
    • Chandra Discovery of a 100 kiloparsec X-Ray Jet in PKS 0637–752 

      Schwartz, D. A.; Marshall, H. L.; Lovell, J. E. J.; Piner, B. G.; Tingay, S. J.; Birkinshaw, M.; Chartas, G.; Elvis, Martin S.; Feigelson, E. D.; Ghosh, K. K.; Harris, D. E.; Hirabayashi, H.; Hooper, E. J.; Jauncey, D. L.; Lanzetta, K. M.; Mathur, S.; Preston, R. A.; Tucker, W. H.; Virani, S.; Wilkes, Belinda Jane; Worrall, Diana M. (IOP Publishing, 2000)
      The quasar PKS 0637-752, the first celestial X-ray target of the Chandra X-Ray Observatory, has revealed asymmetric X-ray structure extending from 3'' to 12'' west of the quasar, coincident with the inner portion of the ...
    • The Chandra Multi-wavelength Project: Optical Spectroscopy and the Broadband Spectral Energy Distributions of X-Ray-selected AGNs. 

      Trichas, Markos; Green, Paul J.; Silverman, John D.; Aldcroft, Tom; Barkhouse, Wayne; Cameron, Robert A.; Constantin, Anca; Ellison, Sara L.; Foltz, Craig; Haggard, Daryl; Jannuzi, Buell T.; Kim, Dong-Woo; Marshall, Herman L.; Mossman, Amy E.; Pérez, Laura M.; Romero-Colmenero, Encarni; Ruiz, Angel; Smith, Malcolm G.; Smith, Paul S.; Torres, Guillermo; Wik, Daniel R.; Wilkes, Belinda Jane; Wolfgang, Angie (IOP Publishing, 2012)
      From optical spectroscopy of X-ray sources observed as part of ChaMP, we present redshifts and classifications for a total of 1569 Chandra sources from our targeted spectroscopic follow up using the FLWO, SAAO, WIYN, CTIO, ...
    • Chandra Multiwavelength Project X‐Ray Point Source Catalog 

      Kim, Minsun; Kim, Dong‐Woo; Wilkes, Belinda Jane; Green, Paul J.; Kim, Eunhyeuk; Anderson, Craig Stephen; Barkhouse, Wayne A.; Evans, Nancy Remage; Ivezi?, ?eljko; Karovska Neily, Margarita; Kashyap, Vinay L.; Lee, Myung Gyoon; Maksym, W. Peter; Mossman, Amy E.; Silverman, John D.; Tananbaum, Harvey D. (IOP Publishing, 2007)
      We present the Chandra Multiwavelength Project (ChaMP) X-ray point source catalog with ~6800 X-ray sources detected in 149 Chandra observations covering ~10 deg2. The full ChaMP catalog sample is 7 times larger than the ...
    • Chandra Multiwavelength Project X‐Ray Point Source Number Counts and the Cosmic X‐Ray Background 

      Kim, Minsun; Wilkes, Belinda Jane; Kim, Dong‐Woo; Green, Paul J.; Barkhouse, Wayne A.; Lee, Myung Gyoon; Silverman, John D.; Tananbaum, Harvey D. (IOP Publishing, 2007)
      We present the Chandra Multiwavelength Project (ChaMP) X-ray point source number counts and cosmic X-ray background (CXRB) flux densities in multiple energy bands. From the ChaMP X-ray point source catalog, ~5500 sources ...
    • Chandra Multiwavelength Project. I. First X‐Ray Source Catalog 

      Kim, D.‐W.; Cameron, R. A.; Drake, Jeremy J.; Evans, Nancy Remage; Freeman, P.; Gaetz, Terrance J.; Ghosh, H.; Green, P. J.; Harnden, F. R. Jr.; Karovska Neily, Margarita; Kashyap, Vinay L.; Maksym, W. Peter; Ratzlaff, Peter W; Schlegel, E. M.; Silverman, J. D.; Tananbaum, Harvey D.; Vikhlinin, Alexey A.; Wilkes, Belinda Jane; Grimes, J. P. (IOP Publishing, 2004)
      The Chandra Multiwavelength Project (ChaMP) is a wide-area (~14 deg2) survey of serendipitous Chandra X-ray sources, aiming to establish fair statistical samples covering a wide range of characteristics (such as absorbed ...