English

Forward Modeling of the $δ$ Sct Star V1790 Ori: $Δν$, $Ω$, Resolution and Non-adiabatic Effects

Solar and Stellar Astrophysics 2026-07-21 v1

Abstract

We investigate the role of large separation, rotational correction order, structural resolution, and non-adiabatic effects in modelling the rotating δ\delta Scuti star V1790 Ori. From TESS data, we extract 69 frequencies and determine Δν82\Delta\nu \simeq 82 μ\muHz. Rotating MESA models are computed at low and high resolution; their pulsation frequencies are calculated with GYRE (adiabatic/non-adiabatic, first-order rotation) and FILOU (adiabatic, second-order rotation). Using Δν\Delta\nu as a structural constraint is necessary to reduce model degeneracy. For the selected minimum-misfit reference model, considering only the 40 modes with consistent (n,,m)(n,\ell,m) labels, the RMS40_{40} theoretical frequency differences are 0.442 μ\muHz (resolution), 0.062 μ\muHz (non-adiabatic), and 2.962 μ\muHz (GYRE vs FILOU); including all 48 frequencies gives RMS48_{48} values of 1.033, 2.326, and 3.931 μ\muHz. Relative to observations, higher resolution reduces residuals from 4.457 to 4.387 μ\muHz (RMS40_{40}) and from 4.715 to 4.682 μ\muHz (RMS48_{48}); non-adiabatic effects change them marginally to 4.381 and 4.673 μ\muHz. FILOU gives the largest residuals: 5.331 μ\muHz (RMS40_{40}) and 5.270 μ\muHz (RMS48_{48}). Second-order rotation produces the largest frequency shifts, but improving agreement with observations requires denser grids and self-consistent FILOU optimisation. The 260.672 μ\muHz peak -- previously identified as the fundamental radial mode -- shows uncertain identification. The results should be interpreted as diagnostics of modelling systematics and mode-identification robustness.

Keywords

Cite

@article{arxiv.2607.18889,
  title  = {Forward Modeling of the $δ$ Sct Star V1790 Ori: $Δν$, $Ω$, Resolution and Non-adiabatic Effects},
  author = {Xiaoya Sun and Antonio García Hernández and Zhaoyu Zuo and Juan Carlos Suárez and Yifan Wang and Ruixuan Tang and Giovanni M. Mirouh and Taozhi Yang},
  journal= {arXiv preprint arXiv:2607.18889},
  year   = {2026}
}

Comments

17 pages, 9 figures, accepted for publication in A&A