| Title |
"Temporary GPS/HFP" radio sources / |
| Authors |
Kovalev, Y.Y |
| Full Text |
|
| Is Part of |
Baltic astronomy. 2005, Vol. 14, no. 3, p. 413-416.. ISSN 1392-0049 |
| Keywords [eng] |
Galaxies ; Radio continuum |
| Abstract [eng] |
For investigation of the nature of GPS/HFP ('gigahertz peaked-spectrum / high-frequency peakers', possible young developing radio sources) it is important to construct robust, representative flux-density-limited samples. To look for spectra of the GPS/HFP type, we have used our RATAN-600 instantaneous broad-band 1-22 GHz spectra measurements of about 2000 compact extragalactic radio sources done in 1997-2003. We have found that some objects from published GPS/HFP samples change their spectra in time becoming non-GPS/HFP sources. We call such objects "temporary GPS/HFP" and suggest to use them cautiously. GPS/HFP-like type of spectrum can often be produced by an AGN during early stages of strong radio flares. and usually such a spectrum evolves to a flat one. A GPS-type spectrum could also be observed during a quiescent state of a relativistic jet when emission of an extended, slowly variable component of the source dominates. Some new GPS candidates are also found. |
| Type |
Journal article |
| Language |
English |
| Publication date |
2005 |
