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arXiv · 2401.01091

Period-Luminosity Relationship for $\delta$ Scuti Stars Revisited

Atila Poro·S. Javad Jafarzadeh·Roghaye Harzandjadidi·Mohammad Madani·Elnaz Bozorgzadeh·Esfandiar Jahangiri·Ahmad Sarostad·Ailar Alizadehsabegh·Maryam Hadizadeh·Mohammad EsmaeiliVakilabadi
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Abstract

The Gaia DR3 parallax approach was used to estimate the absolute parameters of 2375 Delta Scuti stars from the ASAS catalog. The selected stars have a variety of observational characteristics, with a higher than 80% probability of being Delta Scuti stars. We have displayed all the stars in the Hertzsprung-Russell (H-R) diagram along with the Delta Scuti instability strip, the Zero Age Main Sequence (ZAMS), and the Terminal-Age Main Sequence (TAMS). Then, we determined which fundamental and overtone modes each star belongs to using pulsation constant (Q) calculations. In addition, we evaluated the parameters in the Q calculation equation using three machine learning methods, which showed that surface gravity and temperature have the greatest effect on its calculation. The Period-Luminosity (P-L) relationship of the Delta Scuti stars was also revisited. Eventually, using least squares linear regression, we made four linear fits for fundamental and overtone modes and updated their relationships.

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Atila Poro, S. Javad Jafarzadeh, Roghaye Harzandjadidi, Mohammad Madani, Elnaz Bozorgzadeh, Esfandiar Jahangiri, Ahmad Sarostad, Ailar Alizadehsabegh, Maryam Hadizadeh, Mohammad EsmaeiliVakilabadi. 2024-01-02. Period-Luminosity Relationship for $\delta$ Scuti Stars Revisited. https://arxiv.org/abs/2401.01091

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