Frequency patterns as the key to unlock the secrets of pulsations in $$\delta$$ Scuti stars
• +3
• Antonio García Hernández,
• Susana Martín-Ruiz,
• Awaiting Activation,
• Juan Carlos Suárez,
• Daniel Reese,
• Awaiting Activation
Antonio García Hernández
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Susana Martín-Ruiz
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Awaiting Activation
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Juan Carlos Suárez
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Daniel Reese
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Awaiting Activation
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## Abstract

Delta Scuti ($$\delta$$ Sct) stars are intermediate-mass pulsators whose intrinsic oscillations have been studied for decades. However, modelling their pulsations remains a real theoretical challenge, thereby even hampering the precise determination of global stellar parameters. Here we present a direct and precise measurement of the mean density of $$\delta$$ Sct stars. This measurement is obtained from an observational relation that scales stellar mean density with an oscillation frequency pattern analogous to the solar-like large separation but in the low order regime. We also show that this relation is independent of the rotation rate of the star, thus allowing us to accurately determine the mass and the radius, constrain the evolutionary stage, and estimate the rotational velocity. This places tight constraints on stellar evolution theory and on the physical properties of planets orbiting A-type stars.