11 papers
The Stellar Observations Network Group (SONG) -- A Legacy Archive of Stellar Time-Domain Spectroscopy
M. N. Lund, F. Grundahl, M. S. Fredslund +35
The Stellar Observations Network Group (SONG) network has operated for more than a decade, providing long-baseline, high-cadence spectroscopic observations of bright stars and the…
Wildly Oscillating Stars -- Unexplained dense ridge-like frequency agglomerations in A and F type pulsators
V. Antoci, J. Labadie-Bartz, M. Swiech +14
We investigate the origin of the dense, ridge-like frequency clusters observed in a subset of A and F type pulsating stars, which we refer to as `wildly oscillating' stars (WOS). T…
Calibration of the [C/N] and [Y/Mg] chemical clocks with asteroseismic ages from the TESS space mission
E. PakÅ¡tienÄ, G. TautvaiÅ¡ienÄ, V. Bagdonas +8
Context. Stellar ages are typically very difficult to estimate for field stars. New empirical methods, based on abundance ratios of chemical elements, are emerging and need to be c…
A Test of Substellar Evolutionary Models with High-Precision Ages from Asteroseismology and Gyrochronology for the Benchmark System HR 7672AB
Yaguang Li, Michael C. Liu, Trent J. Dupuy +35
We present high-precision measurements for HR~7672AB, composed of a Sun-like (G0V) star and an L~dwarf companion. Three nights of precise (70 cm/s) radial velocity (RV) asteroseism…
Oscillation frequencies and mode lifetimes in alpha Centauri A
Timothy R. Bedding, Hans Kjeldsen, R. Paul Butler +5
We analyse our recently-published velocity measurements of alpha Cen A (Butler et al. 2004). After adjusting the weights on a night-by-night basis in order to optimize the window f…
Glitch analysis and asteroseismic modelling of subgiant Herculis: confirming and interpreting the peak as the helium glitch
Advik Gupta, Kuldeep Verma, Hans Kjeldsen +7
The measurements of pressure-mode and mixed-mode oscillation frequencies in subgiant stars offer a unique opportunity to probe their internal structures -- from the surface to the…