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Detailed understanding of stellar physics is essential towards a robustdetermination of stellar properties (e.g. radius, mass, and age). Among thevital input physics used in the modelling of solar-type stars which remainpoorly constrained, is the initial helium abundance. To this end, whenconstructing stellar model grids, the initial helium abundance is estimatedeither (i) by using the semi-empirical helium-to-heavy element enrichmentratio, (${\Delta Y}/{\Delta Z}$), anchored to the standard Big BangNucleosynthesis value or (ii) by setting the initial helium abundance as a freevariable. Adopting 35 low-mass, solar-type stars with multi-year Keplerphotometry from the asteroseismic "LEGACY" sample, we explore the systematicuncertainties on the inferred stellar parameters (i.e., radius, mass, and age)arising from the treatment of the initial helium abundance in stellar modelgrids . The stellar masses and radii derived from grids with free initialhelium abundance are lower compared to those from grids based on a fixed${\Delta Y}/{\Delta Z}$ ratio. We find the systematic uncertainties on meandensity, radius, mass, and age arising from grids which employ a fixed value of${\Delta Y}/{\Delta Z}$ and those with free initial helium abundance to be$\sim$ 0.9%, $\sim$ 2%, $\sim$ 5% and $\sim$ 29%, respectively. We report thatthe systematic uncertainties on the inferred masses and radii arising from thetreatment of initial helium abundance in stellar grids lie within the expectedaccuracy limits of ESA's PLATO, although this is not the case for the age.

Asteroseismic modelling of solar-type stars: A deeper look at the treatment of initial helium abundance