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arXiv · 2508.18589

Characterizing bright $\delta$ Scuti pulsators using TESS lightcurves

Prasad Mani·Timothy R. Bedding·Mara Bernizzoni·Simon J. Murphy·Daniel Hey
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Abstract

We present a study of bright, young $\delta$ Scuti stars near the zero-age main sequence using TESS light curves and Gaia DR3 data. From a sample of 2041 stars with G<7 and $G_{BP}-G_{RP}$ colour in the range 0-0.6, we identified 444 $\delta$ Scuti pulsators. We measured a pulsator fraction of ~70% in the middle of the instability strip, tapering off towards the edges. A period - luminosity diagram reveals a concentration along the fundamental mode and overtone ridges. We addressed sample completeness and identified low-frequency pulsators possibly exhibiting mixed modes. Cross-matching with nearby young associations showed that 63 $\delta$ Scuti stars from our sample are association members.

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Prasad Mani, Timothy R. Bedding, Mara Bernizzoni, Simon J. Murphy, Daniel Hey. 2025-08-26. Characterizing bright $\delta$ Scuti pulsators using TESS lightcurves. https://doi.org/10.1093/mnras%2Fstaf1400

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