Now showing items 1902-1921 of 18256

    • Chandra Multiwavelength Project: Normal Galaxies at Intermediate Redshift 

      Kim, D.‐W.; Barkhouse, W. A.; Romero‐Colmenero, E.; Green, P. J.; Kim, M.; Mossman, Amy E.; Schlegel, E.; Silverman, J. D.; Aldcroft, Thomas L.; Anderson, C.; Ivezic, Z.; Kashyap, V.; Tananbaum, Harvey D.; Wilkes, Belinda Jane (IOP Publishing, 2006)
      We have investigated 136 Chandra extragalactic sources, including 93 galaxies with narrow emission lines (NELGs) and 43 with only absorption lines (ALGs). Based on fX/fO, LX, X-ray spectral hardness, and optical emission-line ...
    • The Chandra Multiwavelength Project: Optical Follow‐up of Serendipitous Chandra Sources 

      Green, P. J.; Silverman, J. D.; Cameron, R. A.; Kim, D.‐W.; Wilkes, Belinda Jane; Barkhouse, W. A.; LaCluyze, A.; Morris, D.; Mossman, Amy E.; Ghosh, H.; Grimes, J. P.; Jannuzi, B. T.; Tananbaum, Harvey D.; Aldcroft, Thomas L.; Baldwin, J. A.; Chaffee, F. H.; Dey, A.; Dosaj, A.; Evans, Nancy Remage; Fan, X.; Foltz, C.; Gaetz, Terrance J.; Hooper, E. J.; Kashyap, Vinay L.; Mathur, S.; McGarry, M. B.; Romero‐Colmenero, E.; Smith, M. G.; Smith, P. S.; Smith, R. C.; Torres, Guillermo; Vikhlinin, Alexey A.; Wik, D. R. (IOP Publishing, 2004)
      We present follow-up optical g', r', and i' imaging and spectroscopy of serendipitous X-ray sources detected in six archival Chandra images included in the Chandra Multiwavelength Project (ChaMP). Of the 486 X-ray sources ...
    • A Chandra Observation of 3C 288—Reheating ohe Cool Core of a 3 Kev Cluster from a Nuclear Outburst at Z = 0.246 

      Lal, D. V.; Kraft, Ralph P.; Forman, William R.; Hardcastle, M. J.; Jones, C.; Nulsen, Paul; Evans, D. A.; Croston, J. H.; Lee, Julia C (IOP Publishing, 2010)
      We present results from a 42 ks Chandra/ACIS-S observation of the transitional FR I/FR II radio galaxy 3C 288 at z = 0.246. We detect ~3 keV gas extending to a radius of ~0.5 Mpc with a 0.5-2.0 keV luminosity of 6.6 × 1043 ...
    • Chandra Observation of Abell 2142: Survival of Dense Subcluster Cores in a Merger 

      Markevitch, M.; Ponman, T. J.; Nulsen, P. E. J.; Bautz, M. W.; Burke, D. J.; David, L. P.; Davis, D.; Donnelly, R. H.; Forman, W. R.; Jones, C.; Kaastra, J.; Kellogg, E.; Kim, D.-W.; Kolodziejczak, J.; Mazzotta, P.; Pagliaro, A.; Patel, S.; Van Speybroeck, L.; Vikhlinin, A.; Vrtilek, J.; Wise, M.; Zhao, P. (American Astronomical Society, 2000)
      We use Chandra data to map the gas temperature in the central region of the merging cluster A2142. The cluster is markedly nonisothermal; it appears that the central cooling flow has been disturbed but not destroyed by a ...
    • Chandra Observations of the 'Dark' Moon and Geocoronal Solar Wind Charge Transfer 

      Wargelin, B. J.; Markevitch, M.; Juda, M.; Kharchenko, V.; Edgar, R.; Dalgarno, A. (American Astronomical Society, 2004)
      We have analyzed data from two sets of calibration observations of the Moon made by the Chandra X-Ray Observatory. In addition to obtaining a spectrum of the bright side that shows several distinct fluorescence lines, we ...
    • Chandra Study of an Overdensity of X-Ray Sources around Two Distant (z ~ 0.5) Clusters 

      Cappi, M.; Mazzotta, P.; Elvis, Martin S.; Burke, D. J.; Comastri, A.; Fiore, F.; Forman, William R.; Fruscione, Antonella; Green, P.; Harris, D.; Hooper, E. J.; Jones, C.; Kaastra, J. S.; Kellogg, E.; Murray, S.; McNamara, Brian David; Nicastro, F.; Ponman, T. J.; Schlegel, E. M.; Siemiginowska, Aneta L.; Tananbaum, Harvey D.; Vikhlinin, Alexey A.; Virani, S.; Wilkes, Belinda Jane (IOP Publishing, 2001)
      We present results from a Chandra X-Ray Observatory study of the field X-ray source populations in four different observations: two high-redshift (z ~ 0.5) clusters of galaxies 3C 295 and RX J003033.2+261819; and two ...
    • A Chandra Survey of Broad Absorption Line Quasars 

      Green, Paul J.; Aldcroft, Thomas L.; Mathur, Smita; Wilkes, Belinda Jane; Elvis, Martin (IOP Publishing, 2001)
      We have carried out a survey with the Chandra X-Ray Observatory of a sample of 10 bright broad absorption line (BAL) quasars (QSOs). Eight of 10 sources are detected. The six brightest sources have only high-ionization ...
    • The Chandra Survey of Extragalactic Sources in the 3cr Catalog: X-Ray Emission From Nuclei, Jets, and Hotspots in the Chandra Archival Observations 

      Massaro, F.; Harris, D. E.; Liuzzo, E.; Orienti, M.; Paladino, R.; Paggi, A.; Tremblay, G. R.; Wilkes, Belinda Jane; Kuraszkiewicz, Joanna; Baum, S. A.; O’Dea, C. P. (IOP Publishing, 2015)
      As part of our program to build a complete radio and X-ray database of all Third Cambridge catalog extragalactic radio sources, we present an analysis of 93 sources for which Chandra archival data are available. Most of ...
    • Chandra X-ray Observations of 12 Millisecond Pulsars in the Globular Cluster M28 

      Bogdanov, Slavko; van den Berg, Maureen; Servillat, Mathieu; Heinke, Craig O.; Grindlay, Jonathan E.; Stairs, Ingrid H.; Ransom, Scott M.; Freire, Paulo C. C.; Bégin, Steve; Becker, Werner (American Astronomical Society, 2011)
      We present a Chandra X-ray Observatory investigation of the millisecond pulsars in the globular cluster M28 (NGC 6626). In what is one of the deepest X-ray observations of a globular cluster, we firmly detect seven and ...
    • Chandra X-Ray Observations of the Redshift 1.53 Radio-Loud Quasar 3c 270.1 

      Wilkes, Belinda Jane; Lal, Dharam V.; Worrall, Diana M.; Birkinshaw, Mark; Haas, Martin; Willner, Steven P.; Antonucci, Robert; Ashby, Matthew L N; Avara, Mark; Barthel, Peter; Chini, Rolf; Fazio, Giovanni Gene; Hardcastle, Martin; Lawrence, Charles; Leipski, Christian; Ogle, Patrick; Schulz, Bernhard (IOP Publishing, 2012)
      Chandra X-ray observations of the high redshift (z = 1.532) radio-loud quasar 3C 270.1 in 2008 February show the nucleus to have a power-law spectrum, Γ = 1.66 ± 0.08, typical of a radio-loud quasar, and a marginally ...
    • Chandra x-ray sources in the collapsed-core globular cluster M30 (NGC 7099) 

      Lugger, Phyllis M.; Cohn, Haldan N.; Heinke, Craig O.; Grindlay, Jonathan E.; Edmonds, Peter D. (American Astronomical Society, 2007)
      We report the detection of six discrete, low-luminosity (L-X < 10(33) ergs s(-1)) X- ray sources, located within 12" of the center of the collapsed-core globular cluster M30 (NGC 7099), and a total of 13 sources within ...
    • Chandra X‐Ray Observations of 19 Millisecond Pulsars in the Globular Cluster 47 Tucanae 

      Bogdanov, Slavko; Grindlay, Jonathan E.; Heinke, Craig O.; Camilo, Fernando; Freire, Paulo C. C.; Becker, Werner (American Astronomical Society, 2006)
      We present spectral and long-timescale variability analyses of Chandra X-Ray Observatory ACIS-S observations of the 19 millisecond pulsars (MSPs) with precisely known positions in the globular cluster 47 Tucanae. The X-ray ...
    • Chandra X‐Ray Observatory Observations of the Globular Cluster M28 and Its Millisecond Pulsar PSR B1821−24 

      Becker, Werner; Swartz, Douglas A.; Pavlov, George G.; Elsner, Ronald F.; Grindlay, Jonathan; Mignani, Roberto; Tennant, Allyn F.; Backer, Don; Pulone, Luigi; Testa, Vincenzo; Weisskopf, Martin C. (American Astronomical Society, 2003)
      We report here the results of the first Chandra X- Ray Observatory observations of the globular cluster M28 ( NGC 6626). We detect 46 X- ray sources, of which 12 lie within 1 core radius of the center. We show that the ...
    • Chandra X‐Ray Observatory Observations of the Globular Cluster M71 

      Elsner, Ronald F.; Heinke, Craig O.; Cohn, Haldan N.; Lugger, Phyllis M.; Maxwell, J. Edward; Stairs, Ingrid H.; Ransom, Scott M.; Hessels, Jason W. T.; Becker, Werner; Huang, Regina H. H.; Edmonds, Peter D.; Grindlay, Jonathan E.; Bogdanov, Slavko; Ghosh, Kajal; Weisskopf, Martin C. (American Astronomical Society, 2008)
    • The Chandra X‐Ray Observatory Resolves the X‐Ray Morphology and Spectra of a Jet in PKS 0637-752 

      Chartas, G.; Worrall, Diana M.; Birkinshaw, Mark; Cresitello‐Dittmar, M.; Cui, W.; Ghosh, K. K.; Harris, D. E.; Hooper, E. J.; Jauncey, D. L.; Kim, Dong-Woo; Lovell, J.; Mathur, S.; Schwartz, Daniel Alan; Tingay, S. J.; Virani, S. N.; Wilkes, Belinda Jane (IOP Publishing, 2000)
      The core-dominated radio-loud quasar PKS 0637-752 (z = 0.654) was the first celestial object observed with the Chandra X-Ray Observatory, offering the early surprise of the detection of a remarkable X-ray jet. Several ...
    • Chandra, MDM, Swift, and NuSTAR Observations Confirming the SFXT Nature of AX J1949.8+2534 

      Hare, Jeremy; Clavel, Maïca; Rahoui, Farid; Tomsick, John A.; Grindlay, Jonathan; Halpern, Jules (American Astronomical Society, 2019-06-07)
      AX J1949.8+2534 is a candidate supergiant fast X-ray transient (SFXT) observed in outburst by the International Gamma-ray Astrophysics Laboratory (IGR J19498+2534). We report on the results of six Neil Gehrels Swift-XRT, ...
    • ChandraACIS Survey of M33 (ChASeM33): X‐Ray Imaging Spectroscopy of M33SNR 21, the Brightest X‐Ray Supernova Remnant in M33 

      Gaetz, Terrance J.; Blair, William P.; Hughes, John P.; Winkler, P. Frank; Long, Knox S.; Pannuti, Thomas G.; Williams, Benjamin; Edgar, Richard J.; Ghavamian, Parviz; Plucinsky, Paul P.; Sasaki, Manami; Kirshner, Robert P.; Avillez, Miguel; Breitschwerdt, Dieter (American Astronomical Society, 2007)
      We present and interpret new X-ray data for M33SNR 21, the brightest X-ray supernova remnant (SNR) in M33. The SNR is in seen projection against ( and appears to be interacting with) the bright H II region NGC 592. Data ...
    • Chandrahigh-resolution Observations of Cid-42, A Candidate Recoiling Supermassive Black Hole 

      Civano, F.; Elvis, M.; Lanzuisi, G.; Aldcroft, T.; Trichas, M.; Bongiorno, A.; Brusa, M.; Blecha, L.; Comastri, A.; Loeb, A.; Salvato, M.; Fruscione, A.; Koekemoer, A.; Komossa, S.; Gilli, R.; Mainieri, V.; Piconcelli, E.; Vignali, C. (American Astronomical Society, 2012)
      We present Chandra High Resolution Camera observations of CID-42, a candidate recoiling supermassive black hole (SMBH) at z = 0.359 in the COSMOS survey. CID-42 shows two optical compact sources resolved in the HST/ACS ...
    • ChandraStudy of a Complete Sample of Millisecond Pulsars in 47 Tucanae and NGC 6397 

      Grindlay, J. E.; Camilo, F.; Heinke, C. O.; Edmonds, P. D.; Cohn, H.; Lugger, P. (American Astronomical Society, 2002)
    • A Change Has Come: Race, Politics, and the Path to the Obama Presidency 

      Bobo, Lawrence D.; Dawson, Michael C. (Cambridge University Press, 2009)
      Has Barack Obama's success transformed the racial divide? Did he somehow transcend or help bring to an end centuries of racial division in the United States? Did he deliberately run a strategically race-neutral, race-evading ...