PLATO Hare-and-Hounds exercise: Asteroseismic model fitting of\n main-sequence solar-like pulsators

Abstract

Asteroseismology is a powerful tool to infer fundamental stellar properties.\nThe use of these asteroseismic-inferred properties in a growing number of\nastrophysical contexts makes it vital to understand their accuracy.\nConsequently, we performed a hare-and-hounds exercise where the hares simulated\ndata for 6 artificial main-sequence stars and the hounds inferred their\nproperties based on different inference procedures. To mimic a pipeline such as\nthat planned for the PLATO mission, all hounds used the same model grid. Some\nstars were simulated using the physics adopted in the grid, others a different\none. The maximum relative differences found (in absolute value) between the\ninferred and true values of the mass, radius, and age were 4.32 per cent, 1.33\nper cent, and 11.25 per cent, respectively. The largest systematic differences\nin radius and age were found for a star simulated assuming gravitational\nsettling, not accounted for in the model grid, with biases of -0.88 per cent\n(radius) and 8.66 per cent (age). For the mass, the most significant bias\n(-3.16 per cent) was found for a star with a helium enrichment ratio outside\nthe grid range. Moreover, a ~7 per cent dispersion in age was found when\nadopting different prescriptions for the surface corrections or shifting the\nclassical observations by $\\pm 1\\sigma$. The choice of the relative weight\ngiven to the classical and seismic constraints also impacted significantly the\naccuracy and precision of the results. Interestingly, only a few frequencies\nwere required to achieve accurate results on the mass and radius. For the age\nthe same was true when at least one $l=2$ mode was considered.\n