Astronomy and Astrophysics – Astrophysics – Instrumentation and Methods for Astrophysics
Scientific paper
2009-12-08
Astronomy and Astrophysics
Astrophysics
Instrumentation and Methods for Astrophysics
9 pages, 4 figures, 2 tables
Scientific paper
Visibility-visibility correlation has been proposed as a technique for the estimation of power spectrum, and used extensively for small field of view observations, where the effect of $w-term$ is usually ignored. We consider power spectrum estimation from the large field of view observations, where the $w-term$ can have a significant effect. Our investigation shows that a nonzero $w$ manifests itself as a modification of the primary aperture function of the instrument. Using a gaussian primary beam, we show that the modified aperture is an oscillating function with a gaussian envelope. We show that the two visibility correlation reproduces the power spectrum beyond a certain baseline given by the width, $U_{w}$ of the modified aperture. Further, for a given interferometer, the maximum $U_{w}$ remains independent of the frequencies of observation. This suggests that, the incorporation of large field of view in radio interferometric observation has a greater effect for larger observing wavelengths.
Dutta Prasun
Khastgir Pratik S.
Sarkar Tapomoy Guha
No associations
LandOfFree
The Effect of $w-term$ on Visibility Correlation and Power Spectrum Estimation 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 The Effect of $w-term$ on Visibility Correlation and Power Spectrum Estimation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Effect of $w-term$ on Visibility Correlation and Power Spectrum Estimation will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-386452