Synchrotron Spectra and Ages of Compact Steep Spectrum Radio Sources

نویسندگان

  • M. Murgia
  • M. Vigotti
چکیده

The high-frequency integrated spectra of Compact Steep Spectrum (CSS) sources show breaks with a moderate spectral steepening well fitted by continuous injection synchrotron spectra. In lobe-dominated CSS sources the radiative ages deduced by the synchrotron theory are in the range of up to 10 years, if equipartition magnetic fields are assumed. These radiative ages are well correlated with the source size indicating that the CSS sources are young. In order to maintain the frustration scenario, in which the sources’ lifetimes are ≈ 10 years, their equipartition magnetic field would be systematically decreased by a factor >∼ 20. To complete the sample used in this work, we conducted observations at 230 GHz with the IRAM 30-m telescope of those sources which did not have such high-frequency observations up to now.

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تاریخ انتشار 1999