Solar cycle variation of νmax in helioseismic data and its implications for asteroseismology

Research output: Contribution to journalArticle

Colleges, School and Institutes

Abstract

The frequency, νmax, at which the envelope of pulsation power peaks for solar-like oscillators is an important quantity in asteroseismology. We measure νmax for the Sun using 25 yr of Sun-as-a-star Doppler velocity observations with the Birmingham Solar-Oscillations Network (BiSON), by fitting a simple model to binned power spectra of the data. We also apply the fit to Sun-as-a-star Doppler velocity data from Global Oscillation Network Group and Global Oscillations at Low Frequency, and photometry data from VIRGO/SPM on the ESA/NASA SOHO spacecraft. We discover a weak but nevertheless significant positive correlation of the solar νmax with solar activity. The uncovered shift between low and high activity, of  ≃25μHz, translates to an uncertainty of 0.8 per cent in radius and 2.4 per cent in mass, based on direct use of asteroseismic scaling relations calibrated to the Sun. The mean νmax in the different data sets is also clearly offset in frequency. Our results flag the need for caution when using νmax in asteroseismology.

Bibliographic note

6 pages, 4 figures, published in MNRAS Letters, 2020, vol 493, pages L49 - 53 Corrected error in metadata list of authors

Details

Original languageEnglish
Pages (from-to)L49-L53
Number of pages5
JournalMonthly Notices of the Royal Astronomical Society
Volume493
Issue number1
Early online date8 Jan 2020
Publication statusPublished - Mar 2020

Keywords

  • astro-ph.SR, asteroseismology, Sun: helioseismology, Sun: activity