A new way to infer variations of the seismic solar radius

TL;DR

This paper introduces a novel seismic holography method to measure temporal variations in the Sun's seismic radius, revealing a correlation with solar activity cycles and consistent with previous helioseismology findings.

Contribution

It demonstrates a new approach using seismic holography to infer solar radius variations, aligning with and extending prior helioseismic research.

Findings

Seismic phase varies with the solar cycle

Seismic radius changes by a few kilometers between solar maximum and minimum

Results are consistent with global helioseismology studies

Abstract

We show that the mean phase of waves propagating all the way from the far side of the Sun to the front side, as measured by seismic holography, varies with time. The change is highly anticorrelated with solar cycle activity and is consistent with other recent results on the variation of the seismic radius of the Sun. The phase change that we observe corresponds to a few kilometers difference in the seismic solar radius from solar maximum to solar minimum in agreement with inferrences from global helioseismology studies.