Gravity-mode period spacings of the hybrid γ Doradus/δ Scuti star HD 49434

The gravity (g-) mode pulsations of γ Doradus stars are ideal probes of the convective core boundary, and their non-equidistant spacings, a robust measure of near-core rotation and chemical mixing. For hybrid stars which also pulsate in pressure modes, this can be extended to the outer envelope, enabling differential studies and unparalleled constraints on stellar structure. Our work aimed to identify the pulsation frequencies of a candidate hybrid γ Doradus\δ Scuti star and use these to inform its g-mode period spacings. We used iterative prewhitening to extract the pulsation frequencies and then group these according to spectroscopic geometric description, forming the basis of the search for period spacings in the datasets. Our results suggest HD 49434 exhibits 12 successive quadrupole (l=2) sectoral (l=m) g modes and 6 successive dipole (l=1) sectoral g modes in the form of two distinct patterns of decreasing period spacing. Additionally, the large local dips in the quadrupole series suggest mode trapping in layers of chemical inhomogeneity. The detection of independent modes in the γ Doradus and δ Scuti regimes is confirmation that HD 49434 pulsates in both pressure modes and g modes. The patterns presented in this analysis provide a strong foundation for the future asteroseismic analysis of HD 49434, enabling a better understanding of stars in the hybrid regime.