Rotating Stars and the Formation of Bipolar Planetary Nebulae. II. Tidal Spin-up
We present new binary stellar evolution models that include the effects of tidal forces, rotation, and magnetic torques with the goal of testing planetary...
Rotation of Hot Horizontal-Branch Stars in the Globular Clusters NGC 1904, NGC 2808, NGC 6093, and NGC 7078
We present high-resolution Very Large Telescope/Ultraviolet Visual Echelle Spectrograph observations of 56 stars in the extended horizontal-branch (EHB) of the...
Rotation of Solar Analogs Crossmatching Kepler and Gaia DR2
A major obstacle to interpreting the rotation period distribution for main-sequence stars from Kepler mission data has been the lack of a precise evolutionary...
RR Lyrae Mid-infrared Period-Luminosity-Metallicity and Period-Wesenheit-Metallicity Relations Based on Gaia DR3 Parallaxes
We present new empirical infrared period-luminosity-metallicity (PLZ) and period-Wesenheit-metallicity (PWZ) relations for RR Lyae based on the latest Gaia...
SALT3-NIR: Taking the Open-source Type Ia Supernova Model to Longer Wavelengths for Next-generation Cosmological Measurements
A large fraction of Type Ia supernova (SN Ia) observations over the next decade will be in the near-infrared (NIR), at wavelengths beyond the reach of the...
Scattering Polarization and Hanle Effect in Stellar Atmospheres with Horizontal Inhomogeneities
Scattering of light from an anisotropic source produces linear polarization in spectral lines and in the continuum. In the outer layers of a stellar atmosphere...
Scattering Polarization in the Ca II Infrared Triplet with Velocity Gradients
Magnetic field topology, thermal structure, and plasma motions are the three main factors affecting the polarization signals used to understand our star. In...
Scattering Polarization in the Fe I 630 nm Emission Lines at the Extreme Limb of the Sun
Spectro-polarimetric observations with the Solar Optical Telescope onboard Hinode reveal the emission spectrum of the Fe I 630 nm lines at the solar limb. The...