M

Stickel, Eberhard; Groffmann, Hans-Dieter; Rau, Karl-Heinz

doi:10.1007/978-3-663-12126-8_13

Cited by 22 publications

(47 citation statements)

References 6 publications

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“…For the sake of discussion, we classify the terminal knot, K2.5, as the radio ''hot spot'' in the context of similar X-ray detected features in other powerful jets (see below and x 3.3). Stickel (1993) noted also an 8.5 GHz VLA detection of this terminal feature by Patnaik et al (1992) from a 100 s observation, although no image is presented. These four data sets form the basis of our radio analysis of the jet.…”

Section: Very Large Arraymentioning

confidence: 87%

“…It was identified as one of the highest redshift X-ray quasars at the time of its discovery (z ¼ 3:87; Becker et al 1992) from spectroscopic follow-up of statistically significant sources from the Einstein Observatory. Further optical spectroscopy by Stickel (1993) refined the redshift to z ¼ 3:89, affirmed by Hook et al (1995); the latter value is adopted here. After the Einstein detection, it was established as a bona fide X-ray source by ROSAT (Röntgensatellit;Fink & Briel 1993), ASCA (Advanced Satellite for Cosmology and Astrophysics; Kubo et al 1997), and BeppoSAX (Donato et al 2005).…”

Section: Introductionmentioning

confidence: 84%

“…Due to the large distance of the quasar, and hence related observational difficulties, these accretion parameters cannot be evaluated precisely thus should be treated with some caution. Nevertheless, we note Stickel (1993) and Stickel & Kühr (1993) found a broad emission C iv line in the spectrum of the 1745+624 quasar at the observed wavelength k obs C iv ¼ 7553 8, and an observed FWHM obs C iv ¼ 64:9 8. This gives the intrinsic velocity dispersion…”

Section: The Jet Energeticsmentioning

confidence: 91%

“…Radio emission would be radiated by these electrons at very low frequencies (tens of MHz in this case) and subarcsecond-resolution radio imaging capabilities at these energies are not widely available. Curiously, Stickel (1993) noticed that the integrated radio spectrum of 1745+624 contains a steep-spectrum excess at low frequencies; this quasar would be cataloged as a steepspectrum radio quasar in low-frequency surveys and /or if it were local (the 1 þ z shift in observed frequencies). In our own compilation of radio data from the literature (Fig.…”

Section: Relativistic Beamed X-ray Emission?mentioning

confidence: 97%

“…This can be taken as a lower limit in this case because the relation was calibrated for the broad component of the CIV line, which was not measured independently from the narrow one (Stickel 1993;Stickel & Kühr 1993); including the latter underestimates the measured broad-line width (Vestergaard 2002), which could be >3000 km s À1 . The corresponding Eddington luminosity is L Edd k 10 47 ergs s À1 , and the Eddington ratio is Ã $ L bol /L Edd $ 1 10.…”

Section: The Jet Energeticsmentioning

confidence: 97%

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Confronting X‐Ray Emission Models with the Highest Redshift Kiloparsec‐Scale Jets: Thez = 3.89 Jet in Quasar 1745+624

Cheung

Stawarz

Siemiginowska

2006

ApJ

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A newly identified kiloparsec-scale X-ray jet in the high-redshift z ¼ 3:89 quasar 1745+624 is studied with multifrequency radio, HST, and Chandra X-ray imaging data. This is only the third large-scale X-ray jet beyond z > 3 known and is further distinguished as being the most luminous relativistic jet observed at any redshift, exceeding 10 45 ergs s À1 in both the radio and X-ray bands. Apart from the jet's extreme redshift and luminosity, its basic properties, such as X-ray/radio morphology, radio polarization, and the convex broadband spectral energy distributions of three distinct knots are also similar to lower z examples. Relativistically beamed inverse Compton and ''nonstandard'' synchrotron models have been considered to account for such excess X-ray emission in other jets; both models are applicable here, but with differing requirements for the underlying jet physical properties, such as velocity, energetics, and electron acceleration processes. One potentially very important distinguishing characteristic between the two models is their strongly diverging predictions for the X-ray/radio emission with increasing redshift. This is considered, although with the limited sample of three z > 3 jets it is apparent that future studies targeted at very highredshift jets are required for further elucidation. Finally, from the broadband jet emission we estimate the jet kinetic power to be no less than 10 46 ergs s À1 , which is about 10% of the Eddington luminosity corresponding to this galaxy's central supermassive black hole mass M BH k10 9 M estimated here via the virial relation. The optical luminosity of the quasar core is about 10 times over Eddington, hence the inferred jet power seems to be much less than that available from mass accretion. The apparent super-Eddington accretion rate may, however, suggest contribution of an unresolved jet in the observed optical nucleus.

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Section: Very Large Arraymentioning

confidence: 87%

Section: Introductionmentioning

confidence: 84%

Section: The Jet Energeticsmentioning

confidence: 91%

Section: Relativistic Beamed X-ray Emission?mentioning

confidence: 97%

Section: The Jet Energeticsmentioning

confidence: 97%

See 3 more Smart Citations

Confronting X‐Ray Emission Models with the Highest Redshift Kiloparsec‐Scale Jets: Thez = 3.89 Jet in Quasar 1745+624

Cheung

Stawarz

Siemiginowska

2006

ApJ

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Cosmic Infrared Background: ISOPHOT FIR Source Counts at 90, 150 and 180 μm

Juvela

Mattila

Lemke

2000

ISO Surveys of a Dusty Universe

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Far-infrared maps obtained with ISOPHOT have been searched for point-like sources. The majority of the 55 sources is believed to be extragalactic and in most cases no previously known sources can be associated with them. Based on the far-infrared spectral energy distributions it is likely that dust-enshrouded, distant galaxies form a significant fraction of the sources.We estimate the number densities of extragalactic sources at 90µm, 150µm and 180µm wavelengths and at flux density levels down to ∼100 mJy. The counts are compared with models of galaxy evolution. The counts exceed the predictions of current models, even those with strong evolution, and no-evolution models are rejected at a high confidence level.Comparison with recent results from COBE mission indicates that at 90µm the detected sources correspond to > ∼ 20% of the extragalactic background light. At longer wavelengths the corresponding fraction is 10%.

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Normal Galaxies in the Infrared

Hélou

Astronomie Spatiale Infrarouge, Aujourd’hui Et Demain Infrared Space Astronomy, Today and Tomorrow

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M

Cited by 22 publications

References 6 publications

Confronting X‐Ray Emission Models with the Highest Redshift Kiloparsec‐Scale Jets: Thez = 3.89 Jet in Quasar 1745+624

Confronting X‐Ray Emission Models with the Highest Redshift Kiloparsec‐Scale Jets: Thez = 3.89 Jet in Quasar 1745+624

Cosmic Infrared Background: ISOPHOT FIR Source Counts at 90, 150 and 180 μm

Normal Galaxies in the Infrared

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