Abstract Details
| Name: Mrinmoy Sarkar Affiliation: Aryabhatta Research Institute of Observational Sciences Conference ID: ASI2025_151 Title : Asteroseismology of the mild Am delta Sct star HD 118660: TESS photometry and modelling Authors and Co-Authors : Mrinmoy Sarkar 1 , 2 Santosh Joshi 1, Marc-Antoine Dupret 3, Otto Trust 4, Peter De Cat 5, Eugene Semenko 6, Patricia Lampens 5, Aruna Goswami 7, David Mkrtichian 6, Drisya Karinkuzhi 8, Ilya Yakunin 9, Archana Gupta 2 Abstract Type : Poster Abstract Category : Stars, Interstellar Medium, and Astrochemistry in Milky Way Abstract : We present the results of an asteroseismic study of HD 118660 (TIC 171729860), a chemically peculiar (mild Am) star exhibiting delta scuti pulsations. It is based on the analysis of two sectors of time-series photometry from the space mission TESS ( Transiting Exoplanet Survey Satellite ) and seismic modelling. It yielded the detection of 15 and 16 frequencies for TESS sectors 23 and 50, respectively. The identified pulsation modes include four radial ( l = 0) and five dipolar ( l = 1) ones. The radial modes are overtones with order n ranging from 3 and 6. Such high values of n are theoretically not expected for stars with the effective temperature of HD 118660 ( Teff ≈ 7550 K) located near the red edge of the delta scuti instability strip. To estimate the asteroseismic parameters, we have generated a grid of stellar models assuming a solar metallicity ( Z = 0.014) and different values for the convective overshooting parameter (0.1 ≤ αov ≤ 0.3). We conclude that the analysis of the radial modes is insufficient to constrain αov and Z for delta scuti stars. The value for the equatorial velocity of HD 118660 derived from the seismic radius and the rotational frequency is consistent with values found in the literature. |