CLEAN (algorithm)
Encyclopedia
The CLEAN algorithm is a computational algorithm to perform a deconvolution
on images created in radio astronomy
. It was published by Jan Högbom in 1974 and several variations have been proposed since then .
The algorithm assumes that the image consists of a number of point sources. It will iteratively find the highest value in the image and subtract a small gain of this point source convolved with the point spread function
("dirty beam") of the observation, until the highest value is smaller than some threshold.
Deconvolution
In mathematics, deconvolution is an algorithm-based process used to reverse the effects of convolution on recorded data. The concept of deconvolution is widely used in the techniques of signal processing and image processing...
on images created in radio astronomy
Radio astronomy
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The initial detection of radio waves from an astronomical object was made in the 1930s, when Karl Jansky observed radiation coming from the Milky Way. Subsequent observations have identified a number of...
. It was published by Jan Högbom in 1974 and several variations have been proposed since then .
The algorithm assumes that the image consists of a number of point sources. It will iteratively find the highest value in the image and subtract a small gain of this point source convolved with the point spread function
Point spread function
The point spread function describes the response of an imaging system to a point source or point object. A more general term for the PSF is a system's impulse response, the PSF being the impulse response of a focused optical system. The PSF in many contexts can be thought of as the extended blob...
("dirty beam") of the observation, until the highest value is smaller than some threshold.