Binarity as the Origin of Long Secondary Periods in Red Giant Stars [PDF]
Astrophysical Journal Letters, 2021 Long secondary periods (LSPs), observed in a third of pulsating red giant stars, are the only unexplained type of large-amplitude stellar variability known at this time.
I. Soszy'nski +15 more
semanticscholar +1 more source
Seismic signature of electron degeneracy in the core of red giants: hints for mass transfer between close red-giant companions [PDF]
Astronomy & Astrophysics, 2021 The detection of mixed modes in red giants with space missions CoRoT and Kepler has revealed their deep internal structure. These modes allow us to characterize the pattern of pressure modes (through the measurement of their asymptotic frequency ...
S. Deheuvels +3 more
semanticscholar +1 more source
Distances to PHANGS Galaxies: New Tip of the Red Giant Branch Measurements and Adopted Distances [PDF]
Monthly notices of the Royal Astronomical Society, 2020 PHANGS-HST is an ultraviolet-optical imaging survey of 38 spiral galaxies within ∼20 Mpc. Combined with the PHANGS-ALMA, PHANGS-MUSE surveys and other multiwavelength data, the dataset will provide an unprecedented look into the connections between ...
G. Anand +35 more
semanticscholar +1 more source
A Red Giants’ Toy Story. II. Understanding the Red-giant Branch Bump
The Astrophysical Journal, 2023 The Red-Giant Branch Bump (RGBB) is one of the most noteworthy features in the red-giant luminosity function of stellar clusters. It is caused by the passage of the hydrogen-burning shell through the composition discontinuity left at the point of the ...
Marcelo M. Miller Bertolami
doaj +1 more source
The Parallax of ω Centauri Measured from Gaia EDR3 and a Direct, Geometric Calibration of the Tip of the Red Giant Branch and the Hubble Constant [PDF]
, 2020 We use data from the ESA Gaia mission Early Data Release 3 (EDR3) to measure the trigonometric parallax of ω Cen, the first high-precision parallax measurement for the most massive globular cluster in the Milky Way. We use a combination of positional and
J. Soltis, S. Casertano, A. Riess
semanticscholar +1 more source
The Carnegie-Chicago Hubble Program. VIII. An Independent Determination of the Hubble Constant Based on the Tip of the Red Giant Branch [PDF]
Astrophysical Journal, 2019 We present a new and independent determination of the local value of the Hubble constant based on a calibration of the tip of the red giant branch (TRGB) applied to Type Ia supernovae (SNe Ia). We find a value of H0 = 69.8 ± 0.8 (±1.1% stat) ± 1.7 (±2.4%
W. Freedman +12 more
semanticscholar +1 more source
Population Synthesis of Helium White Dwarf–Red Giant Star Mergers and the Formation of Lithium-rich Giants and Carbon Stars [PDF]
Astrophysical Journal, 2020 The formation histories of lithium-rich and carbon-rich red giants are not yet understood. It has been proposed that the merger of a helium-core white dwarf with a red giant branch (RGB) star might provide a solution. We have computed an extended grid of
Xianfei Zhang +3 more
semanticscholar +1 more source
Rotationally Driven Ultraviolet Emission of Red Giant Stars [PDF]
Astronomical Journal, 2020 Main-sequence stars exhibit a clear rotation-activity relationship, in which rapidly rotating stars drive strong chromospheric/coronal ultraviolet and X-ray emission.
Don M. Dixon, J. Tayar, K. Stassun
semanticscholar +1 more source
Dynamical Substructures of Galactic Globular Clusters II. NGC 6934 [PDF]
Journal of Astronomy and Space Sciences, 2004 The variations of the dynamical substructures of NGC 6934 have been investigated by means of performing point spread function stellar photometry and the surface photometry on BV CCD images of NGC 6934.
Jongwhan Rhee +3 more
doaj +1 more source
Inferring Coupling Strengths of Mixed-mode Oscillations in Red Giant Stars Using Deep Learning
The Astrophysical Journal, 2023 Asteroseismology is a powerful tool that may be applied to shed light on stellar interiors and stellar evolution. Mixed modes, behaving like acoustic waves in the envelope and buoyancy modes in the core, are remarkable because they allow for probing the ...
Siddharth Dhanpal +5 more
doaj +1 more source