Sven Buder

Double Trouble: How Unresolved Spectroscopic Binary Stars Skew GALAH DR4 Stellar Parameters

Abstract Unresolved binary stars introduce systematic biases in stellar parameter estimates when analysed assuming a single star. Using ~917,000 spectra from the Galactic Archaeology with HERMES (GALAH) Data Release 4 (DR4), we develop a binary spectral model that fits each obser...