Full Stokes polarimetric observations with a single-dish radio-telescope

Details Full Stokes polarimetric observations with a single-dish radio-telescope Full Stokes polarimetric observations with a single-dish radio-telescope

2009-01-29

arxiv.org/abs/0901.4720v1

Astronomy and Astrophysics

Astrophysics

Instrumentation and Methods for Astrophysics

10 pages, to be published in A&A

Scientific paper

The study of the linear and circular polarization in AGN allows one to gain detailed information about the properties of the magnetic fields in these objects. However, especially the observation of circular polarization (CP) with single-dish radio-telescopes is usually difficult because of the weak signals to be expected. Normally CP is derived as the (small) difference of two large numbers (LHC and RHC); hence an accurate calibration is absolutely necessary. Our aim is to improve the calibration accuracy to include the Stokes parameter V in the common single-dish polarimetric measurements, allowing a full Stokes study of the source under examination. A detailed study, up to the 2nd order, of the Mueller matrix elements in terms of cross-talk components allows us to reach the accuracy necessary to study circular polarization. The new calibration method has been applied to data taken at the 100-m Effelsberg radio-telescope during regular test observations of extragalactic sources at 2.8, 3.6, 6 and 11 cm. The D-terms in phase and amplitude appear very stable with time and the few known values of circular polarization have been confirmed. It is shown that, whenever a classical receiver and a multiplying polarimeter are available, the proposed calibration scheme allows one to include Stokes V in standard single-dish polarimetric observations as difference of two native circular outputs.

Affiliated with

Also associated with

No associations

Rating

Full Stokes polarimetric observations with a single-dish radio-telescope 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 Full Stokes polarimetric observations with a single-dish radio-telescope, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Full Stokes polarimetric observations with a single-dish radio-telescope will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-13874