Time-Distance Solar Far-Side Imaging Using Three-Skip Acoustic Signals

TL;DR

This paper introduces a new three-skip acoustic signal method for solar far-side imaging, enhancing image quality by combining it with existing techniques to improve signal clarity and reduce noise.

Contribution

It presents a novel three-skip helioseismic imaging technique and a new image combination method to improve solar far-side active region detection.

Findings

Three-skip signals can effectively image solar far-side regions.

Combining three-skip images with existing methods enhances image quality.

The new method reduces noise and spurious features in the images.

Abstract

The purpose of this work is to image solar far-side active regions using acoustic signals with three skips and improve the quality of existing images. The mapping of far-side active regions was first made possible using the helioseismic holography technique by use of four-skip acoustic signals. The quality of far-side images was later improved with the combination of four- and five-skip signals using the time-distance helioseismology technique. In this work, we explore the possibility of making three-skip far-side images of active regions, and improving the image quality by combining the three-skip images with the images obtained from existing techniques. A new method of combining images is proposed that increases the signal-to-noise ratio and reduces the appearance of spurious features.