The GALAH survey : effective temperature calibration from the InfraRed Flux Method in the Gaia system

• In order to accurately determine stellar properties, knowledge of the effective temperature of stars is vital. We implement Gaia and 2MASS photometry in the InfraRed Flux Method and apply it to over 360000 stars across different evolutionary stages in the GALAH DR3 survey. We derive colour-effective temperature relations that take into account the effect of metallicity and surface gravity over the range 4000K ⪅ T-eff ⪅ 8000 K, from very metal-poor stars to supersolar metallicities. The internal uncertainty of these calibrations is of order 40-80 K depending on the colour combination used. Comparison against solar-twins, Gaia benchmark stars, and the latest interferometric measurements validates the precision and accuracy of these calibrations from F to early M spectral types. We assess the impact of various sources of uncertainties, including the assumed extinction law, and provide guidelines to use our relations. Robust solar colours are also derived.

Ämnesord

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Nyckelord

techniques: photometric

stars: abundances

stars: atmospheres

stars: fundamental parameters

stars: Hertzsprung-Russell and colour-magnitude diagrams

infrared: stars

Publikations- och innehållstyp

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