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arXiv · 2609.00294

Statistical analysis of asteroseismic indices and stellar parameters of TESS-observed $\delta$ Scuti stars

C. Lv·A. Esamdin·A. Hasanzadeh·M. Ghazinejad·J. Pascual-Granado·G. M. Mirouh·R. Karimov
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Abstract

We analyze the statistical properties and asteroseismic indices of delta Scuti stars observed during TESS Cycle 4. Using 2 minute cadence photometry and Fourier analysis, we identified 765 delta Scuti stars in Sectors 40-55, including 179 objects with low-resolution stellar parameters from LAMOST. We examined the distributions of their pulsation and stellar parameters using values from the TESS Input Catalog and LAMOST. Most targets lie within the classical instability strip, follow the period-luminosity relation, and show periods, amplitudes, temperatures, surface gravities, and luminosities consistent with delta Scuti stars. For the LAMOST subsample, we estimated the large frequency separation ($\Delta\nu$), $\nu_{\rm max}$, and $\nu({\rm Amax})$ using an empirical relation and a two-dimensional autocorrelation method. We also derived relations among these asteroseismic indices. This catalog provides a useful sample for future studies of the internal structure and evolution of delta Scuti stars.

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C. Lv, A. Esamdin, A. Hasanzadeh, M. Ghazinejad, J. Pascual-Granado, G. M. Mirouh, R. Karimov. 2026-08-31. Statistical analysis of asteroseismic indices and stellar parameters of TESS-observed $\delta$ Scuti stars. https://doi.org/10.1051/0004-6361%2F202346985

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