Asteroseismology of a Double-mode High-amplitude δ Scuti Star TIC 448892817 Lv, Chenglong Pascual Granado, Javier García Hernández, Antonio Asteroseismology Delta Scuti variable stars Stellar oscillations We thank the anonymous referee for the suggestive comments, which improved the manuscript. We would like to thank the TESS science team for providing such excellent data. J.P.G. acknowledges funding support from Spanish public funds for research from project PID2019-107061GB-C63 from the “Programas Estatales de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I+D +i y de I+D+i Orientada a los Retos de la Sociedad”, and from the State Agency for Research through the “Center of Excellence Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709), all from the Spanish Ministry of Science, Innovation and Universities (MCIU). A.G.H. acknowledges support from “FEDER/Junta de Andalucía- Consejería de Economía y Conocimiento” under project E-FQM-041-UGR18 by Universidad de Granada. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) is a National Major Scientific Project built by the Chinese Academy of Sciences. Funding for the project has been provided by the National Development and Reform Commission. LAMOST is operated and managed by the National Astronomical Observatories, Chinese Academy of Sciences. We propose that TIC 448892817 is a double-mode high-amplitude δ Scuti star. The radial modes detected in this star provide a unique opportunity to exploit asteroseismic techniques up to their limits. 30 significant frequencies are detected by frequency analysis, while two of them are independent frequencies, i.e., F0 = 13.43538(2) day−1 and F1 = 17.27007(4) day−1. The ratio of f1/f2 is measured to be 0.777957(2), suggesting that this target is a double-mode δ Scuti star. Nearly all the light variation is due to these two modes and their combination frequencies, but several other frequencies of very low amplitude are also present. The stellar evolutionary models were constructed with different mass M and metallicity Z using Modules for Experiments in Stellar Astrophysics (MESA). The frequency ratio f1/f2 obtained by the model is smaller than those obtained by observation. This might be caused by the rotation of the star pointing that rotational effects are more important than previously thought in HADS stars. This is something that deserves to be investigated in future works with models including rotational effects for moderate to intermediate rotators such as FILOU. On the other hand, the parameters obtained from MESA agree well with previous results as well as by observational spectra. The best-fitting model shows that TIC 448892817 is close to entering the first turnoff of the main sequence. In order to accurately determine the effective temperature and metallicities, thus further narrowing the parameter space of this star, we suggest high-resolution spectra is highly desired in the future. 2022-11-29T08:58:18Z 2022-11-29T08:58:18Z 2022-10-26 info:eu-repo/semantics/article Chenglong Lv et al. Asteroseismology of a Double-mode High-amplitude δ Scuti Star TIC 448892817. 2022 AJ 164 218 [DOI 10.3847/1538-3881/ac9473] https://hdl.handle.net/10481/78166 10.3847/1538-3881/ac9473 eng http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Atribución 4.0 Internacional American Astronomical Society