Total flux density radio observations as a tool for understanding AGN behaviour

Details Total flux density radio observations as a tool for understanding AGN behaviour Total flux density radio observations as a tool for understanding AGN behaviour

Oct 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007ap%26ss.311..347l&link_type=abstract

Astrophysics and Space Science, Volume 311, Issue 1-3, pp. 347-351

Astronomy and Astrophysics

Astrophysics

Galaxies: Active, Bl Lacertae Objects: General, Quasars: General, Radio Continuum: Galaxies

Scientific paper

A wealth of information on the properties of jets in Active Galactic Nuclei (AGNs) can be derived from total flux density observations at high radio frequencies. This includes, for example, the Doppler factor, the Lorentz factor, and the viewing angle of the jet. We have earlier calculated these parameters for a sample of ˜80 sources of different AGN types using almost 20 years of 22 and 37 GHz data from Metsähovi Radio Observatory. We have now gathered data for an additional ten years, and studied the long term characteristic variability time scales of a large sample of AGNs using the first order structure function, the discrete autocorrelation function and the Lomb-Scargle periodogram. Some of the results will be presented in this paper. We also stress the importance of long term observations of AGNs, the main reason for this being misinterpretations of source properties due to insufficient time coverage. Only a few observing epochs will too easily lead to incorrect conclusions about variability, continuum spectra, and the general detectability of the source, not to mention the exclusion of interesting objects from further studies. This is particularly important when considering, for example, the Planck satellite for which the quality of the main mission product, the accurate cosmic microwave background anisotropy maps, depends heavily on the elimination of foreground sources such as AGNs.

Affiliated with

Also associated with

No associations

Rating

Total flux density radio observations as a tool for understanding AGN behaviour does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Total flux density radio observations as a tool for understanding AGN behaviour, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Total flux density radio observations as a tool for understanding AGN behaviour will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-825149