TY - JOUR
T1 - Mending the structural surface effect of 1D stellar structure models with non-solar metallicities based on interpolated 3D envelopes
AU - Jørgensen, Andreas Christ Sølvsten
AU - Weiss, Achim
AU - Angelou, George
AU - Aguirre, Víctor Silva
PY - 2019/4
Y1 - 2019/4
N2 - One-dimensional (1D) stellar evolution codes employ rudimentary treatments of turbulent convection. For stars with convective envelopes, this leads to systematic errors in the predicted oscillation frequencies needed for asteroseismology. One way of mending these structural inadequacies is through patching, whereby the outermost layers of 1D models are replaced by the mean stratifications from three-dimensional (3D) simulations. In order to viably implement this approach in asteroseismic analysis, interpolation throughout pre-computed 3D envelopes is required. We present a method that interpolates throughout pre-computed 3D envelopes as a function of effective temperature, surface gravity, and metallicity. We conduct a series of validation tests that demonstrate that the scheme reliably and accurately reproduces the structures of stellar envelopes and apply our method to the Sun as well as two stars observed by Kepler. We parametrize the frequency shift that results from patching and show that the functional forms are evolutionary dependent. In addition, we find that neglecting modal effects, such as non-adiabatic energetics, introduces systematic errors in asteroseimically obtained stellar parameters. Both these results suggest that a cautious approach is necessary when utilizing empirical surface corrections in lieu of patching models. Our results have important implications, particularly for characterizing exoplanet systems, where accuracy is of utmost concern.
AB - One-dimensional (1D) stellar evolution codes employ rudimentary treatments of turbulent convection. For stars with convective envelopes, this leads to systematic errors in the predicted oscillation frequencies needed for asteroseismology. One way of mending these structural inadequacies is through patching, whereby the outermost layers of 1D models are replaced by the mean stratifications from three-dimensional (3D) simulations. In order to viably implement this approach in asteroseismic analysis, interpolation throughout pre-computed 3D envelopes is required. We present a method that interpolates throughout pre-computed 3D envelopes as a function of effective temperature, surface gravity, and metallicity. We conduct a series of validation tests that demonstrate that the scheme reliably and accurately reproduces the structures of stellar envelopes and apply our method to the Sun as well as two stars observed by Kepler. We parametrize the frequency shift that results from patching and show that the functional forms are evolutionary dependent. In addition, we find that neglecting modal effects, such as non-adiabatic energetics, introduces systematic errors in asteroseimically obtained stellar parameters. Both these results suggest that a cautious approach is necessary when utilizing empirical surface corrections in lieu of patching models. Our results have important implications, particularly for characterizing exoplanet systems, where accuracy is of utmost concern.
KW - Asteroseismology
KW - Stars: atmospheres
KW - Stars: interiors
KW - Sun: helioseismology
UR - http://www.scopus.com/inward/record.url?scp=85067058370&partnerID=8YFLogxK
U2 - 10.1093/mnras/stz337
DO - 10.1093/mnras/stz337
M3 - Journal article
AN - SCOPUS:85067058370
SN - 0035-8711
VL - 484
SP - 5551
EP - 5567
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -