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Date and Time of the Query: 2019-05-23 T01:21:12 PDT
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For refcode 1988AJ.....95..307I:
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Copyright by American Astronomical Society. Reproduced by permission
1988AJ.....95..307I ENERGY DISTRIBUTIONS OF BLAZARS C. D. IMPEY Steward Observatory, University of Arizona, Tucson, Arizona 85721-0655 G. NEUGEBAUER Palomar Observatory, Division of Physics, Math, and Astronomy, California Institute of Technology, Pasadena, California 91125 Received 14 September 1987; revised 19 October 1987 ABSTRACT IRAS observations of 162 blazars are presented, with a detection rate of over 50%. The far-infrared data are combined with published data at other wavelengths to complete 93 energy distributions from 10^8^ to 10^18^ Hz. Far-infrared variability is found in ten out of 24 objects, with a typical amplitude of less than half the amplitude at optical wavelengths. Blazars are significantly more variable than quasars or Seyfert galaxies across the entire electromagnetic spectrum, with evidence for a single spectral component from millimeter to optical wavelengths. The range of variability in both spectral index and flux density increases with decreasing wavelength. A general excess of low-frequency emission may represent multiple radio components. The spectra of blazars steepen continuously between 10^9^ and 10^15^ Hz, and the x-ray flux density is often close to an extrapolation of the optical/ ultraviolet continuum. The wavelength at which the energy distribution turns down is ~1.5 mm, with a very narrow range of far-infrared spectral indices. Overall, there is a striking homogeneity in the spectral parameters of the most compact synchrotron component. Half of the blazars with total luminosities less than 10^12^ L_sun_ show evidence for thermal infrared components. Objects with emission lines have a stronger ultraviolet continuum bump than lineless objects. The global energy budget of blazars is dominated by infrared emission from 1 to 100 microns, and the bolometric luminosities range from 10^9^ to 10^14^ L_sun_.
Retrieve 159 NED objects in this reference.
Please click here for ADS abstract

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