7 papers
Towards understanding stellar variability at the sub m/s level: granulation-induced variability across the optical spectrum
Cis Lagae, Ginger Frame, Heather M. Cegla +5
Detecting the radial velocity signal of Earth-mass exoplanets requires the characterisation and removal of granulation-induced radial velocity variability from spectroscopic observ…
HRMOS: A High-Resolution Multi-Object Spectrograph for the VLT
Laura Magrini, Thomas Bensby, Sofia Randich +174
This White Paper presents the scientific rationale and instrument concept for HRMOS (High-Resolution Multi-Object Spectrograph), a next-generation instrument proposed for the ESO V…
Synthetic disk-integrated absorption lines isolating stellar granulation for high-precision RV studies
Ginger Frame, Heather Cegla, Cis Lagae +6
We present a novel method for constructing high-accuracy, time-varying disk-integrated stellar absorption line profiles that isolate the effects of granulation alone. This framewor…
Resolving star spots on WASP-85 A using high-resolution transit spectroscopy
Vedad Kunovac, Heather Cegla, Hritam Chakraborty +23
Stellar surface inhomogeneities such as spots and faculae introduce Doppler variations that challenge exoplanet detection via the radial velocity method. While their impact on disc…
Coupling 1D stellar evolution with 3D-hydrodynamical simulations on-the-fly III: stellar evolution at different metallicities
Yixiao Zhou, Jakob L. Rørsted, Achim Weiss +10
A major weakness in one-dimensional (1D) stellar structure and evolution modeling is the simplified treatment of convection, which leads to erroneous near-surface stratification an…
Towards understanding stellar variability at the sub m/s level: Isolating granulation signals in synthetic spectral lines
Ginger Frame, Heather M. Cegla, Veronika Witzke +5
Granulation in the photospheres of FGK-type stars induces variability in absorption lines, complicating exoplanet detection via radial velocities and characterisation via transmiss…