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In intermediate- to high-mass main sequence stars, fast rotation distorts the stellar surface and scrambles the oscillation spectra. Through the use of 2D models, 2D oscillation calculations and machine learning algorithms, we were able to develop fast and automated techniques to highlight patterns in the spectra. From those we derive stellar mean densities and internal differential rotation, paving the way for mode identification and inversion techniques for these stars. I also introduce a novel pipeline for the spectroscopy of flattened stars, that use these new asteroseismic diagnostics, allowing us to estimate the fundamental parameters and inclination of rotating stars. The future extensions of both techniques are discussed, to predict how we can couple them to reach a complete description of rotating pulsators on the upper main sequence., {"references":["Reese, D. R. 2021, A&A, 645, A46"]}

Using asteroseismic data from the Kepler satellite, we explore the systematic uncertainties arising from changes in the input physics used when constructing evolution models of solar-type stars. We assess the impact of including atomic diffusion and of varying the metallicity mixture on the determination of global stellar parameters (i.e., radius, mass, and age). We find significant systematic uncertainties on global stellar parameters when diffusion is included in stellar grids. Furthermore, we find the systematic uncertainties on the global stellar parameters to be comparable to the statistical uncertainties when a different metallicity mixture is employed in stellar grids., 3 pages, 3 figures, proceeding of PHOST (Physics of Oscillating Stars) - a conference in honour of Prof. H. Shibahashi, 2-7 Sept. 2018, Banyuls-sur-mer (France)

Apart from recent progress in Gamma Dor stars, identifying modes in rapidly rotating stars is a formidable challenge due to the lack of simple, easily identifiable frequency patterns. As a result, it is necessary to look to observational methods for identifying modes. Two popular techniques are spectroscopic mode identification based on line profile variations (LPVs) and photometric mode identification based on amplitude ratios and phase differences between multiple photometric bands. In this respect, the BRITE constellation is particularly interesting as it provides space-based multi-colour photometry. The present contribution describes the latest developments in obtaining theoretical predictions for amplitude ratios and phase differences for pulsation modes in rapidly rotating stars. These developments are based on full 2D non-adiabatic pulsation calculations, using models from the ESTER code, the only code to treat in a self-consistent way the thermal equilibrium of rapidly rotating stars. These predictions are then specifically applied to the BRITE photometric bands to explore the prospects of identifying modes based on BRITE observations., Comment: 8 pages, 3 figures, proceedings of the 3rd BRITE Science Workshop

Using asteroseismic data from the Kepler satellite, we explore the systematic uncertainties arising from changes in the input physics used when constructing evolution models of solar-type stars. We assess the impact of including atomic diffusion and of varying the metallicity mixture on the determination of global stellar parameters (i.e., radius, mass, and age). We find significant systematic uncertainties on global stellar parameters when diffusion is included in stellar grids. Furthermore, we find the systematic uncertainties on the global stellar parameters to be comparable to the statistical uncertainties when a different metallicity mixture is employed in stellar grids.

Using asteroseismic data from the Kepler satellite, we explore the systematic uncertainties arising from changes in the input physics used when constructing evolution models of solar-type stars. We assess the impact of including atomic diffusion and of varying the metallicity mixture on the determination of global stellar parameters (i.e., radius, mass, and age). We find significant systematic uncertainties on global stellar parameters when diffusion is included in stellar grids. Furthermore, we find the systematic uncertainties on the global stellar parameters to be comparable to the statistical uncertainties when a different metallicity mixture is employed in stellar grids., {"references":["Asplund, M., Grevesse, N., Sauval, A. J., & Scott, P. 2009, Annual Review of Astron and Astrophys, 47, 481","Ball, W. H. & Gizon, L. 2014, A & A, 568, A123","Borucki, W. J., Koch, D., Basri, G., Batalha, N., Brown, T., et al. 2010, Science, 327, 977","Campante, T. L., Schofield, M., Kuszlewicz, J. S., Bouma, L., Chaplin, W. J., et al. 2016, ApJ, 830, 138","Cyburt, R. H., Fields, B. D., & Olive, K. A. 2003, Physics Let- ters B, 567, 227","Dotter, A., Conroy, C., Cargile, P., & Asplund, M. 2017, ApJ, 840, 99","Grevesse, N. & Sauval, A. J. 1998, Space Science Reviews, 85, 161","Lund, M. N. & Reese, D. R. 2018, ASSSP, 49, 149","Lund, M. N., Silva Aguirre, V., Davies, G. R., Chaplin, W. J., Christensen-Dalsgaard, J., et al. 2017, ApJ, 835, 172","Nsamba, B., Campante, T. L., Monteiro, M. J. P. F. G., Cunha, M. S., Rendle, B. M., et al. 2018, MNRAS, 477, 5052","Paxton, B., Marchant, P., Schwab, J., Bauer, E. B., Bildsten, L., et al. 2015, ApJS, 220, 15","Rauer, H., Catala, C., Aerts, C., Appourchaux, T., Benz, W., et al. 2014, Experimental Astronomy, 38, 249","Silva Aguirre, V., Davies, G. R., Basu, S., Christensen- Dalsgaard, J., Creevey, O., et al. 2015, MNRAS, 452, 2127","Silva Aguirre, V., Lund, M. N., Antia, H. M., Ball, W. H., Basu, S., et al. 2017, ApJ, 835, 173","Townsend, R. H. D. & Teitler, S. A. 2013, MNRAS, 435, 3406","Valle, G., Dell'Omodarme, M., Prada Moroni, P. G., & Degl'Innocenti, S. 2014, A & A, 561, A125","Valle, G., Dell'Omodarme, M., Prada Moroni, P. G., & Degl'Innocenti, S. 2015, A & A, 575, A12"]}