Frequency and mode identification of {\gamma} Doradus from photometric and spectroscopic observations

TL;DR

This study combines photometric and spectroscopic data to identify pulsation frequencies and modes in the prototype {b3} Doradus star, confirming stability over two decades and establishing it as a key calibrator for future space-based observations.

Contribution

It provides a detailed frequency and mode analysis of the prototype {b3} Doradus star using combined observational methods, confirming long-term stability and aiding asteroseismic modeling.

Findings

Four consistent pulsation frequencies identified.

Three frequencies classified as (l, m) = (1, 1).

Two frequencies stable over twenty years.

Abstract

The prototype star for the {\gamma} Doradus class of pulsating variables was studied em- ploying photometric and spectroscopic observations to determine the frequencies and modes of pulsation. The four frequencies found were self-consistent between the obser- vation types and almost identical to those found in previous studies (1.3641 d-1 ,1.8783 d-1 , 1.4742 d-1 and 1.3209 d-1). Three of the frequencies are classified as l, m = (1, 1) pulsations and the other is ambiguous between l = 2 modes. Two frequencies are shown to be stable over twenty years since their first identification. The agreement in ground-based work makes this star an excellent calibrator for the upcoming TESS observations and a standard for continued asteroseismic modelling.