322 citations · 3.2k across the 60 of their papers we have counts for
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Anti-Solar Differential Rotation May Have Revived Magnetic Braking in the Subgiant 31 Aquilae
Travis S. Metcalfe, Jennifer L. van Saders, Thomas R. Ayres +16
Recent observations have shown that sufficiently slow rotation disrupts the organization of large-scale magnetic field in older main-sequence stars, leading to weakened magnetic br…
Zeeman Doppler Imaging of Ceti: The Weakest Magnetic Field Detected in a Sun-like Star
Federica Chiti, Oleg Kochukhov, Jennifer L. van Saders +1
For nearly a decade, observations have shown that many older Sun-like stars spin faster than predicted, a phenomenon known as weakened magnetic braking (WMB). The leading hypothesi…
Weakened Magnetic Braking Signals the Collapse of the Global Stellar Dynamo
Travis S. Metcalfe, Jennifer L. van Saders, Marc H. Pinsonneault +7
Weakened magnetic braking (WMB) was originally proposed in 2016 to explain anomalously rapid rotation in old field stars observed by the Kepler mission. The proximate cause was sug…
Testing the Rossby Paradigm: Weakened Magnetic Braking in early K-type Stars
Travis S. Metcalfe, Pascal Petit, Jennifer L. van Saders +12
There is an intricate relationship between the organization of large-scale magnetic fields by a stellar dynamo and the rate of angular momentum loss due to magnetized stellar winds…
Extending the Asteroseismic Calibration of the Stellar Rossby Number
Travis S. Metcalfe, Enrico Corsaro, Alfio Bonanno +2
The stellar Rossby number (Ro) is a dimensionless quantity that is used in the description of fluid flows. It characterizes the relative importance of Coriolis forces on convective…
TESS asteroseismology of Hydri: a subgiant with a born-again dynamo
Travis S. Metcalfe, Jennifer L. van Saders, Daniel Huber +12
The solar-type subgiant Hyi has long been studied as an old analog of the Sun. Although the rotation period has never been measured directly, it was estimated to be near 27 day…
A New Asteroseismic Benchmark Constrains the Onset of Weakened Magnetic Braking in Mature Sun-Like Stars
Vanshree Bhalotia, Daniel Huber, Jennifer L. van Saders +11
Stellar spin down is a critical yet poorly understood component of stellar evolution. In particular, results from the Kepler Mission imply that mature age, solar-type stars have in…
Rotation at the Fully Convective Boundary: Insights from Wide WD + MS Binary Systems
Federica Chiti, Jennifer L. van Saders, Tyler M. Heintz +5
Gyrochronology, a valuable tool for determining ages of low-mass stars where other techniques fail, relies on accurate calibration. We present a sample of 185 wide ( au) wh…
The Gasing Pangkah Collaboration: I. Asteroseismic Identification and Characterisation of a Rapidly-Rotating Engulfment Candidate
J. M. Joel Ong, Marc Teng Yen Hon, Melinda Soares-Furtado +19
We report the discovery and characterisation of TIC 350842552 ("Zvrk"), an apparently isolated, rapidly-rotating () red giant observed by TESS in…
Revisiting the Membership, Multiplicity, and Age of the Beta Pictoris Moving Group in the Gaia Era
Rena A. Lee, Eric Gaidos, Jennifer van Saders +2
Determining the precise ages of young (tens to a few hundred Myr) kinematic (``moving") groups is important for placing star, protoplanetary disk, and planet observations on an evo…
Stellar Flares Are Far-Ultraviolet Luminous
Vera L. Berger, Jason T. Hinkle, Michael A. Tucker +6
We identify 182 flares on 158 stars within 100 pc of the Sun in both the near-ultraviolet (NUV: 1750-2750 Å) and far-ultraviolet (FUV: 1350-1750 Å) using high-cadence light curves…
Scaling and Evolution of Stellar Magnetic Activity
Emre Işık, Jennifer L. van Saders, Ansgar Reiners +1
Magnetic activity is a ubiquitous feature of stars with convective outer layers, with implications from stellar evolution to planetary atmospheres. Investigating the mechanisms res…
Stellar Cruise Control: Weakened Magnetic Braking Leads to Sustained Rapid Rotation of Old Stars
Nicholas Saunders, Jennifer L. van Saders, Alexander J. Lyttle +8
Despite a growing sample of precisely measured stellar rotation periods and ages, the strength of magnetic braking and the degree of departure from standard (Skumanich-like) spindo…
The Structure and Evolution of Stars: Introductory Remarks
Dominic M. Bowman, Jennifer van Saders, Jorick S. Vink
In this introductory chapter of the Special Issue entitled `The Structure and Evolution of Stars', we highlight the recent major progress made in our understanding in the physics t…
TESS Stellar Rotation up to 80 days in the Southern Continuous Viewing Zone
Zachary R. Claytor, Jennifer L. van Saders, Lyra Cao +3
The TESS mission delivers time-series photometry for millions of stars across the sky, offering a probe into stellar astrophysics, including rotation, on a population scale. Howeve…
Magnetic activity evolution of solar-like stars: I. S_ph-Age relation derived from Kepler observations
Savita Mathur, Zachary R. Claytor, Angela R. G. Santos +9
The ages of solar-like stars have been at the center of many studies such as exoplanet characterization or Galactic-archaeology. While ages are usually computed from stellar evolut…
Constraints on Magnetic Braking from the G8 Dwarf Stars 61 UMa and Cet
Travis S. Metcalfe, Klaus G. Strassmeier, Ilya V. Ilyin +11
During the first half of their main-sequence lifetimes, stars rapidly lose angular momentum to their magnetized winds, a process known as magnetic braking. Recent observations sugg…
Core-envelope decoupling drives radial shear dynamos in cool stars
Lyra Cao, Marc H. Pinsonneault, Jennifer L. van Saders
Differential rotation is thought to be responsible for the dynamo process in stars like our Sun, driving magnetic activity and star spots. We report that star spot measurements in…
A 4 Gyr M-dwarf Gyrochrone from CFHT/MegaPrime Monitoring of the Open Cluster M67
Ryan Dungee, Jennifer van Saders, Eric Gaidos +5
We present stellar rotation periods for late K- and early M-dwarf members of the 4 Gyr old open cluster M67 as calibrators for gyrochronology and tests of stellar spin-down models.…
The Origin of Weakened Magnetic Braking in Old Solar Analogs
Travis S. Metcalfe, Adam J. Finley, Oleg Kochukhov +10
The rotation rates of main-sequence stars slow over time as they gradually lose angular momentum to their magnetized stellar winds. The rate of angular momentum loss depends on the…
Is [Y/Mg] a Reliable Age Diagnostic for FGK Stars?
Travis A. Berger, Jennifer L. van Saders, Daniel Huber +3
Current spectroscopic surveys are producing large catalogs of chemical abundances for stars of all types. The yttrium to magnesium ratio, [Y/Mg], has emerged as a candidate age ind…
Testing White Dwarf Age Estimates using Wide Double White Dwarf Binaries from Gaia EDR3
Tyler M. Heintz, J. J. Hermes, Kareem El-Badry +4
White dwarf (WD) stars evolve simply and predictably, making them reliable age indicators. However, self-consistent validation of the methods for determining WD total ages has yet…
Rotation Distributions around the Kraft Break with TESS and Kepler: The Influences of Age, Metallicity, and Binarity
Ellis A. Avallone, Jamie N. Tayar, Jennifer L. van Saders +6
Stellar rotation is a complex function of mass, metallicity, and age and can be altered by binarity. To understand the importance of these parameters in main sequence stars, we hav…
Further Evidence of Modified Spin-down in Sun-like Stars: Pileups in the Temperature-Period Distribution
Trevor J. David, Ruth Angus, Jason L. Curtis +5
We combine stellar surface rotation periods determined from NASA's Kepler mission with spectroscopic temperatures to demonstrate the existence of pileups at the long-period and sho…