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Title: Absorption-line spectrum of GC 1556 + 335 - ejected or intervening material

Abstract

Two rich C IV absorption complexes in the radio-loud QSO GC 1556 + 335 are described. Column densities for seven of the redshift systems in these complexes are measured, and limits on the distances between the QSO and absorbing clouds are derived using ionization parameters estimated from matching photoionization models to the observations and a density estimated from an upper limit to the C II(asterisk) column density in the z = 1.65367 redshift system. These limits show that GC 1556 + 335 is not a typical member of the BALQSO class. Two alternative models are discussed in which the absorption complexes are caused by material either entrained into a radio jet from the QSO or contained in two clusters of galaxies along the line of sight. It is suggested that the emission associated with the complexes may be detectable, and that a study of the velocity field and geometry of such emission might be decisive in determining the mechanism responsible for the absorption. 40 references.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Steward Observatory, Tucson, AZ; Multiple Mirror Telescope Observatory, Tucson, AZ; Space Telescope Science Institute, Baltimore, MD; Mount Wilson and Las Campanas Observatories, Pasadena, CA
OSTI Identifier:
6640901
Alternate Identifier(s):
OSTI ID: 6640901
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophys. J.; (United States); Journal Volume: 310
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; QUASARS; ABSORPTION SPECTRA; COSMIC RADIO SOURCES; GALAXY CLUSTERS; KINETIC ENERGY; MATHEMATICAL MODELS; PLASMA JETS; RED SHIFT; ENERGY; SPECTRA 640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar, Radio & X-Ray Sources

Citation Formats

Morris, S.L., Weymann, R.J., Foltz, C.B., Turnshek, D.A., and Shectman, S. Absorption-line spectrum of GC 1556 + 335 - ejected or intervening material. United States: N. p., 1986. Web. doi:10.1086/164663.
Morris, S.L., Weymann, R.J., Foltz, C.B., Turnshek, D.A., & Shectman, S. Absorption-line spectrum of GC 1556 + 335 - ejected or intervening material. United States. doi:10.1086/164663.
Morris, S.L., Weymann, R.J., Foltz, C.B., Turnshek, D.A., and Shectman, S. Sat . "Absorption-line spectrum of GC 1556 + 335 - ejected or intervening material". United States. doi:10.1086/164663.
@article{osti_6640901,
title = {Absorption-line spectrum of GC 1556 + 335 - ejected or intervening material},
author = {Morris, S.L. and Weymann, R.J. and Foltz, C.B. and Turnshek, D.A. and Shectman, S.},
abstractNote = {Two rich C IV absorption complexes in the radio-loud QSO GC 1556 + 335 are described. Column densities for seven of the redshift systems in these complexes are measured, and limits on the distances between the QSO and absorbing clouds are derived using ionization parameters estimated from matching photoionization models to the observations and a density estimated from an upper limit to the C II(asterisk) column density in the z = 1.65367 redshift system. These limits show that GC 1556 + 335 is not a typical member of the BALQSO class. Two alternative models are discussed in which the absorption complexes are caused by material either entrained into a radio jet from the QSO or contained in two clusters of galaxies along the line of sight. It is suggested that the emission associated with the complexes may be detectable, and that a study of the velocity field and geometry of such emission might be decisive in determining the mechanism responsible for the absorption. 40 references.},
doi = {10.1086/164663},
journal = {Astrophys. J.; (United States)},
number = ,
volume = 310,
place = {United States},
year = {Sat Nov 01 00:00:00 EST 1986},
month = {Sat Nov 01 00:00:00 EST 1986}
}
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  • We present the column densities of heavy elements and dust depletion studies in two strong Mg II absorption systems at z {approx} 1.4 displaying the 2175 A dust extinction feature. Column densities are measured from low-ionization absorption lines using an Apparent Optical Depth Method on the Keck/ESI spectra. We find that the dust depletion patterns resemble that of cold diffuse clouds in the Milky Way (MW). The values, [Fe/Zn] {approx}-1.5 and [Si/Zn]<-0.67, are among the highest dust depletion measured for quasar absorption line systems. In another 2175 A absorber at z = 1.64 toward the quasar SDSS J160457.50+220300.5, Noterdaeme etmore » al. reported a similar dust depletion measurement ([Fe/Zn] = -1.47 and [Si/Zn] = -1.07) and detected C I and CO absorption lines on its VLT/UVES spectrum. We conclude that heavy dust depletion (i.e., a characteristic of cold dense clouds in MW) is required to produce a pronounced 2175 A extinction bump.« less
  • We report the detection of a strong H I 21 cm absorption system at z = 0.5344, as well as a candidate system at z = 0.3389, in the sight line toward the z = 2.64 quasar MG J0414+0534. This, in addition to the absorption at the host redshift and the other two intervening absorbers, takes the total to four (possibly five). The previous maximum number of 21 cm absorbers detected along a single sight line is two and so we suspect that this number of gas-rich absorbers is in some way related to the very red color of themore » background source. Despite this, no molecular gas (through OH absorption) has yet been detected at any of the 21 cm redshifts, although, from the population of 21 cm absorbers as a whole, there is evidence for a weak correlation between the atomic line strength and the optical-near-infrared color. In either case, the fact that so many gas-rich galaxies (likely to be damped Ly{alpha} absorption systems) have been found along a single sight line toward a highly obscured source may have far-reaching implications for the population of faint galaxies not detected in optical surveys, a possibility which could be addressed through future wide-field absorption line surveys with the Square Kilometer Array.« less
  • We present the first results from a detailed analysis of photometric and spectrophotometric data on the narrow-line Seyfert 1 (NLS1) galaxy Mrk 335, collected over a 120 day span in the fall of 2010. From these data we measure the lag in the He II {lambda}4686 broad emission line relative to the optical continuum to be 2.7 {+-} 0.6 days and the lag in the H{beta}{lambda}4861 broad emission line to be 13.9 {+-} 0.9 days. Combined with the line width, the He II lag yields a black hole mass M{sub BH} = (2.6 {+-} 0.8) Multiplication-Sign 10{sup 7} M{sub Sunmore » }. This measurement is consistent with measurements made using the H{beta}{lambda}4861 line, suggesting that the He II emission originates in the same structure as H{beta}, but at a much smaller radius. This constitutes the first robust lag measurement for a high-ionization line in an NLS1 galaxy and supports a scenario in which the He II emission originates from gas in virial motion rather than outflow.« less
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