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相关论文: A Chandra Search for X-Ray Jets in Redshift 6 Quas…

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In this letter we report the detection of an extremely strong X-ray emission line in the 940ks chandra ACIS-I spectrum of CXO CDFS J033225.3-274219. The source was identified as a Type1 AGN at redshift of z = 1.617, with 2.0 -- 10.0 keV…

天体物理学 · 物理学 2015-06-24 J. Wang , T. Yaqoob , G. Szokoly , R. Gilli , L. Kewley , V. Mainieri , M. Nonino , P. Rosati , P. Tozzi , W. Zheng , A. Zirm , C. Norman

The complex X-ray morphology of the 300 kpc long X-ray jet in PKS1127-145 (z=1.18 quasar) is clearly discerned in a ~100 ksec Chandra observation. The jet X-ray surface brightness gradually decreases by an order of magnitude going out from…

We present the X-ray properties of a sample of 17 radio sources observed with the Chandra X-ray Observatory as part of a project aimed at studying the X-ray emission from their radio jets. In this paper, we concentrate on the X-ray…

天体物理学 · 物理学 2009-11-07 J. K. Gambill , R. M. Sambruna , G. Chartas , C. C. Cheung , L. Maraschi , F. Tavecchio , C. M. Urry , J. E. Pesce

We investigate the variations of the magnetic field, Doppler factor, and relativistic particle density along the jet of a quasar at z=0.72. We chose 4C 19.44 for this study because of its length and straight morphology. The 18 arcsec length…

We report on two Chandra observations of the quasar PSO J0309+27, the most distant blazar observed so far (z=6.1), performed eight months apart, in March and November 2020. Previous Swift-XRT observation showed that this object is one of…

We report the discovery of five quasars with redshifts of 4.67 - 5.27 and z'-band magnitudes of 19.5-20.7 M_B ~ -27. All were originally selected as distant quasar candidates in optical/near-infrared photometry from the Sloan Digital Sky…

We present new X-ray observations of the nucleus, jet and extended emission of the nearby radio galaxy NGC 6251 using the Chandra/ACIS-S camera, together with a reanalysis of archival Chandra/ACIS-I and XMM-Newton/EPIC data. We find that…

天体物理学 · 物理学 2009-11-10 D. A. Evans , M. J. Hardcastle , J. H. Croston , D. M. Worrall , M. Birkinshaw

We present deep (265 ks) Chandra X-ray observations of PSO J352.4034$-$15.3373, a quasar at z=5.831 that, with a radio-to-optical flux ratio of R>1000, is one of the radio-loudest quasars in the early universe and is the only quasar with…

A brief Chandra observation of the ultraluminous quasar, SDSS J010013.02+280225.8 at redshift 6.326, showed it to be a relatively bright, soft X-ray source with a count rate of about 1 ct/ks. In this paper we present results for the quasar…

In recent years large efforts have been made to detect molecular gas towards high redshifted objects. Up to now the literature reports on only two cases of CO-detection in quasars at a redshift between 1 and 2 - Q0957+561, a gravitationally…

天体物理学 · 物理学 2017-01-18 M. Krips , R. Neri , A. Eckart , J. Martin-Pintado , P. Planesas , L. Colina

A puzzling feature of the {\it Chandra}--detected quasar jets is that their X-ray emission decreases faster along the jet than their radio emission, resulting to an outward increasing radio to X-ray ratio. In some sources this behavior is…

天体物理学 · 物理学 2016-08-30 Markos Georganopoulos , Demosthenes Kazanas

The black hole X-ray transient XTE J1550-564 has undergone a strong outburst in 1998 and two relativistic X-ray jets have been detected years later with the $\it Chandra$ X-ray observatory; the eastern jet was found previously to have…

高能天体物理现象 · 物理学 2012-09-13 J. F. Hao , S. N. Zhang

Quasars at early redshifts ($z > 6$) with companion galaxies offer unique insights into the growth and evolution of the first supermassive black holes. Here, we report on a 150 ks Chandra observation of PSO J308.0416$-$21.2339, a $z=6.23$…

We present Chandra observations of nine high-redshift quasars (z=2.7-5.9) discovered by the Sloan Digital Sky Survey with weak or undetectable high-ionization emission lines in their UV spectra (WLQs). Adding archival X-ray observations of…

We present {\it Chandra} X-ray Observatory observations of Giga-Hertz Peaked Spectrum (GPS) and Compact Steep Spectrum (CSS) radio sources. The {\it Chandra} sample contains 13 quasars and 3 galaxies with measured 2-10 keV X-ray luminosity…

天体物理学 · 物理学 2009-11-13 Aneta Siemiginowska , Stephanie LaMassa , Thomas L. Aldcroft , Jill Bechtold , Martin Elvis

We present a deep high-resolution Chandra X-ray Observatory image data of a powerful compact radio source PKS 0023-26 associated with a quasar at redshift 0.322. The earlier studies of the optical environment suggested that the source could…

星系天体物理 · 物理学 2025-08-01 A. Siemiginowska , R. Morganti , G. Fabbiano , E. O'Sullivan , T. Oosterloo , C. Tadhunter , D. Burke

We present some early results on AGN from the Chandra X-ray Observatory, highlighting high resolution spectroscopy using the High Energy Transmission Grating Spectrometer (HETGS). The quasar PKS 0637-752 was found to have a very bright…

天体物理学 · 物理学 2009-10-31 H. L. Marshall

Observations of positional offsets between the location of X-ray and radio features in many resolved, extragalactic jets indicates that the emitting regions are not co-spatial, an important piece of evidence in the debate over the origin of…

高能天体物理现象 · 物理学 2021-03-24 Karthik Reddy , Markos Georganopoulos , Eileen T. Meyer

Chandra observations of the Vela pulsar-wind nebula (PWN) have revealed a jet in the direction of the pulsar's proper motion, and a counter-jet in the opposite direction, embedded in diffuse nebular emission. The jet consists of a bright,…

天体物理学 · 物理学 2016-08-30 O. Kargaltsev , G. G. Pavlov , M. A. Teter , D. Sanwal

We report preliminary results from the first targets observed as part of a program to image the X-ray jets in a complete sample of radio selected jets. We have acquired Australian Telescope Compact Array and Very Large Array data with…