Choice of pre-main-sequence evolutionary tracks

Determine which pre-main-sequence stellar evolutionary tracks provide the most reliable estimates of stellar masses and ages for the Orion A young stellar population, with particular attention to the differing results obtained from the PISA and Baraffe et al. (2015) models.

Background

The analysis derives stellar masses and ages by placing the Orion A sources on the Hertzsprung–Russell diagram and interpolating evolutionary models. The authors adopt the PISA isochrones because they were specifically computed for the Orion population, while noting that other model grids, such as Baraffe et al. (2015), yield broadly similar population properties but differ in coverage and detailed estimates. The choice of evolutionary tracks therefore remains an unresolved modeling issue that affects inferred stellar and accretion parameters.

References

We note that the choice of evolutionary tracks remains an open debate in the field \citep[e.g.,][]{Zallio_2026,Towner_2026}, though a detailed assessment is beyond the scope of this work.

— X-shooter survey Across Regions and Ages to probe Disk Evolution (ARADE): Accretion properties in Orion A and their relation with disk masses  (2609.00938 - Piscarreta et al., 1 Sep 2026) in Section 3.1, Stellar properties and accretion parameters from UV excess