arXiv subjects

Timothy R. Bedding

Publications and source records attributed to Timothy R. Bedding.

At least 37 records · Page 2Linked to original sources

arXiv2026

TESS observations of the Pleiades cluster: a nursery for delta Scuti stars

We studied 89 A- and F-type members of the Pleiades open cluster, including five escaped members. We measured projected rotational velocities (v sin i) for 49 stars and confirmed that stellar rotation causes a broadening of the main sequence in the color-magnitude diagram. Using time-series photometry from NASA's TESS Mission (plus one star observed by Kepler/K2), we detected delta Scuti pulsations in 36 stars. The fraction of Pleiades stars in the middle of the instability strip that pulsate is unusually high (over 80%), and their range of effective temperatures agrees well with theoretical models. On the other hand, the characteristics of the pulsation spectra are varied and do not correlate with stellar temperature, calling into question the existence of a useful nu_max relation for delta Scutis, at least for young stars. By including delta Scuti stars observed in the Kepler field, we show that the instability strip is shifted to the red with increasing distance by interstellar reddening. Overall, this work demonstrates the power of combining observations with Gaia and TESS for studying pulsating stars in open clusters.

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arXiv2026

Identifying 850 delta Scuti pulsators in a narrow Gaia colour range with TESS 10-minute full-frame images

We use TESS 10-minute Full Frame Images (Sectors 27-55) to study a sample of 1708 stars within 500 pc of the Sun that lie in a narrow colour range in the centre of the delta Scuti instability strip (0.29 < BP-RP < 0.31). Based on the Fourier amplitude spectra, we identify 848 delta Scuti stars, as well as 47 eclipsing or contact binaries. The strongest pulsation modes of some delta Scuti stars fall on the period-luminosity relation of the fundamental radial mode but many correspond to overtones that are approximately a factor of two higher in frequency. Many of the low-luminosity delta Scuti stars show a series of high-frequency modes with very regular spacings. The fraction of stars in our sample that show delta Scuti pulsations is about 70% for the brightest stars (G<8), consistent with results from Kepler. However, the fraction drops to about 45% for fainter stars and we find that a single sector of TESS data only detects the lowest-amplitude delta Scuti pulsations (around 50 ppm) in stars down to about G=9. Finally, we have found four new high-frequency delta Scuti stars with very regular mode patterns, and have detected pulsations in lambda Mus that make it the fourth-brightest delta Scuti in the sky (G=3.63). Overall, these results confirm the power of TESS and Gaia for studying pulsating stars.

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arXiv2026

Characterizing bright $δ$ Scuti pulsators using TESS lightcurves

We present a study of bright, young $δ$ Scuti stars near the zero-age main sequence using TESS light curves and Gaia DR3 data. From a sample of 2041 stars with G<7 and $G_{BP}-G_{RP}$ colour in the range 0-0.6, we identified 444 $δ$ Scuti pulsators. We measured a pulsator fraction of ~70% in the middle of the instability strip, tapering off towards the edges. A period - luminosity diagram reveals a concentration along the fundamental mode and overtone ridges. We addressed sample completeness and identified low-frequency pulsators possibly exhibiting mixed modes. Cross-matching with nearby young associations showed that 63 $δ$ Scuti stars from our sample are association members.

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arXiv2026

RV$\times$TESS I: Modeling Asteroseismic Signals with Simultaneous Photometry and RVs

Detecting small planets via the radial velocity method remains challenged by signals induced by stellar variability, versus the effects of the planet(s). Here, we explore using Gaussian Process (GP) regression with Transiting Exoplanet Survey Satellite (TESS) photometry in modeling radial velocities (RVs) to help to mitigate stellar jitter from oscillations and granulation for exoplanet detection. We applied GP regression to simultaneous TESS photometric and RV data of HD 5562, a G-type subgiant ($M_\star=1.09M_{\odot}$, $R_\star=1.88R_{\odot}$) with a V magnitude of 7.17, using photometry to inform the priors for RV fitting. The RV data is obtained by the Magellan Planet Finder Spectrograph (PFS). The photometry-informed GP regression reduced the RV scatter of HD~5562 from 2.03 to 0.51 m/s. We performed injection and recovery tests to evaluate the potential of GPs for discovering small exoplanets around evolved stars, which demonstrate that the GP provides comparable noise reduction to the binning method. We also found that the necessity of photometric data depends on the quality of the RV dataset. For long baseline and high-cadence RV observations, GP regression can effectively mitigate stellar jitter without photometric data. However, for intermittent RV observations, incorporating photometric data improves GP fitting and enhances detection capabilities.

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arXiv2026

Testing Red Clump Models with the Asteroseismic Binary KIC 10841730

Binaries in which both stars are pulsating are rare but extremely valuable. We present the first study of an asteroseismic binary system consisting of a core helium-burning red clump (RC) star and a red giant branch (RGB) star. The Kepler target KIC 10841730 is a wide binary (period $2917 \pm 8$ d) that provides ideal conditions to test the accuracy of RC models. While prior studies of RC stars have revealed discrepancies in modelling the period spacings of mixed modes, other model parameters remain largely untested. We perform a detailed modelling analysis using individual mode frequencies and cover a large parameter space in mass, metallicity, He-abundance, mixing length, overshooting, and mass-loss, and we also explore different methods to correct for surface effects. We find two possible results for the red clump models. One solution requires introducing an unexpected offset of the phase shift in the red clump model, yielding an age consistent with the companion star and current masses of $1.01 \pm 0.06$ and $1.08 \pm 0.06$ M$_\odot$ for the RC and RGB star, respectively. Alternatively, we find that excluding the identification of two questionable radial modes resolves the phase-shift offset issue but results in a higher mass and thus a much younger age for the red clump star, contradicting the age obtained from its companion. We conclude that uncertainties in red clump models affect not only the g-mode period spacings but also the properties of the p modes. We show the power of asteroseismic binaries in validating and constraining stellar models and highlight the need for refining red-clump models.

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arXiv2026

Asteroseismology of solar-like oscillators: emulating individual mode frequencies with a branching neural network

Accurately measuring stellar ages and internal structures is challenging, but the inclusion of asteroseismic observables can substantially improve precision. However, the curse of dimensionality means this comes at a high computational cost when using standard interpolation methods across grids of stellar models. Furthermore, without a rigorous treatment of random uncertainties in grid-based modelling, it is not possible to address systematic errors in stellar models. We present PITCHFORK -- a multilayer perceptron neural network with a branching architecture capable of rapid emulation of both classical stellar observables and individual asteroseismic oscillation modes of solar-like oscillators. PITCHFORK can predict the classical observables $T_{\text{eff}}$, $L$, and $\left[\mathrm{Fe}/\mathrm{H}\right]$ with precisions of $5.88\,\text{K}$, $0.014\,\text{L}_{\odot}$, and $0.001\,\text{dex}$, respectively, and can predict 35 individual radial mode frequencies with a uniform precision of $0.02$ per cent. PITCHFORK is coupled to a vectorised Bayesian inference pipeline to return well-sampled and fully marginalised posterior distributions. We validate our rigorous treatment of the random uncertainties -- including the asteroseismic surface effect -- in an extensive hare-and-hounds exercise. We also demonstrate our ability to infer the stellar properties of benchmark stars -- namely, the Sun and the binary stars 16 Cygni A and B. This work demonstrates a computationally scalable and statistically robust framework for stellar parameter inference of solar-like oscillators using individual asteroseismic mode frequencies. This provides a foundation for the treatment of systematics in preparation for the imminent abundance of asteroseismic data from future missions.

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arXiv2025

Discovery of 79 $δ$ Scuti Stars in NGC 3532 Suggests a Decrease of Pulsator Occurrence with Age

Many A-F type stars do not display $δ$ Scuti pulsations, despite being located within the instability strip. Open clusters provide a unique opportunity to study $δ$ Scuti pulsations among coeval populations with uniform chemical composition. Here we use data from the TESS Mission to discover 79 $δ$ Scuti pulsators in the 300 Myr old open cluster NGC 3532, the largest number found within a single open cluster to-date. We report a $50\pm5\%$ pulsator fraction in NGC 3532, considerably lower than in younger stellar populations, such the Pleiades (110 Myr), NGC 2516 (100 Myr), and the Cep-Her Complex ($\leq\,$80 Myr), and similar to the pulsator fraction found among field star samples. We introduce the concept of pulsator occurrence, which corrects for incompleteness, and find it to be $63\pm6\%$. For the stars that do pulsate, we find that the hotter stars occupy a distinct branch in the color-magnitude diagram (CMD) due to faster rotation ($>\,$150 km/s) than their non-pulsating counterparts. These results suggest that pulsator occurrence decreases with age and that rapid rotation is important in maintaining $δ$ Scuti pulsations over time. We also investigate the Period-Luminosity (P-L) relation and the $ν_{\rm max}$--$T_{\rm eff}$ relation of $δ$ Scuti stars in NGC 3532. We find much scatter in the P-L relation of the dominant mode and two distinct branches in the $ν_{\rm max}$--$T_{\rm eff}$ relation, similar to the Cep-Her Complex.

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arXiv2025

Asteroseismology of Carbon-Deficient Red Giants: Merger Products of Hierarchical Triple Systems?

Carbon-deficient giants (CDGs) are a rare and chemically peculiar class of stars whose origins remain under active investigation. We present an asteroseismic analysis of the entire known CDG population, selecting 129 stars observed by $Kepler$, K2, and TESS to obtain seismic constraints. We detect solar-like oscillations in 43 CDGs. By measuring $ν_{\rm max}$ and applying seismic scaling relations, we determine precise masses for these stars, finding that 79\% are low-mass ($M \lesssim 2~M_\odot$). The luminosity distribution is bimodal, and the CDGs separate into three chemically and evolutionarily distinct groups, characterized by clear trends in sodium and CNO abundances, $α$-element enhancement, and kinematics. We find that two of these groups are only distinguished by their initial $α$-element abundances, thus effectively reducing the number of groups to two. Lithium enrichment is common across all groups, linking CDGs to lithium-rich giants and suggesting a shared evolutionary origin. We find that spectroscopic $\log g$ is systematically offset from seismic values. Group~1 CDG patterns are most consistent with formation through core He-flash mixing, while the more massive and more chemically processed Groups~2 and 2$α$ likely formed through mergers involving helium white dwarfs, possibly in hierarchical triples. Pollution from AGB stars appears very unlikely, given the unchanged [C+N+O] abundance across all groups.

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arXiv2025

Galactic seismology: can the Gaia 'phase spiral' co-exist with a clumpy, turbulent interstellar medium?

The Gaia satellite revealed a remarkable spiral pattern ('phase spiral', PS) in the z-Vz phase-plane throughout the solar neighbourhood, where z and Vz are the displacement and velocity of a star perpendicular to the Galactic plane. As demonstrated by many groups, the kinematic signature reflects the Galactic stellar disc's response to a dynamical disturbance some 0.3-3 Gyr ago. However, previous controlled simulations did not consider the impact of the multi-phase interstellar medium (ISM) on the existence of the PS. This is crucial because it has been suggested that this weak signal is highly susceptible to scattering by small-scale density fluctuations typical of the ISM. This has motivated us to explore the formation and fate of the PS in a suite of high-resolution, N-body/hydrodynamical simulations of an idealised Galaxy analogue bearing a realistic ISM that interacts impulsively with a massive perturber. In our models, high gas surface densities within the disc encourage vigorous star formation, which in turn couples with the gas via feedback to drive turbulence. We find that the PS is almost non-existent if the disc potential is too strong or the ISM is highly structured on sub-kiloparsec scales. This can happen in the absence of stellar feedback when the gas is allowed to cool. In the presence of turbulent gas maintained by stellar feedback, the PS has a patchy spatial distribution and a high degree of intermittency on kiloparsec scales. We anticipate that future studies of the phase-spiral behaviour on all scales will provide crucial information on star-gas dynamics.

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arXiv2025

The highest mass Kepler red giants -- II. Spectroscopic parameters, the amplitude-activity relation, and unexpected halo orbits

The high-mass (M$>$2 \Msolar{}) Kepler red giant stars are less well-studied than their lower-mass counterparts. In the previous article, we presented a sample of 48 high-mass Kepler red giants and measured their asteroseismic parameters. This article presents spectroscopic measurements from the same sample, using high-resolution Keck/HIRES spectra to determine \Teff{}, [Fe/H], \logg{}, and $v \sin i$. We refined our previous estimates of the stellar masses and radii based on the new \Teff{}. We also examined spectral features that could indicate binary activity, such as the Li line and [C/N] ratios. We found no Li-rich stars or clear [C/N] anomalies, but we observed a correlation between [C/N] and [Fe/H]. We measured chromospheric activity using the $S$-index of the Ca II H \& K lines and found no correlation with internal magnetic fields. However, we confirmed an anti-correlation between surface chromospheric activity and radial mode oscillation amplitudes, which indicates that strong surface magnetic fields weaken stellar oscillations. Finally, we used the Gaia DR3 astrometric data to show that our sample of stars have orbits consistent with all three Galactic kinematic regions. Although these stars are quite young, their orbits carry them into the thick disk and even the halo, raising questions about the accuracy and viability of kinematics in unravelling Galactic history. In future work, we plan to use the spectroscopic parameters measured here to provide better constraints for boutique frequency modelling, which will allow us to test the asteroseismic scaling relations at the high-mass regime.

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arXiv2025

Luminaries in the Sky: The TESS Legacy Sample of Bright Stars. I. Asteroseismic detections in naked-eye main-sequence and sub-giant solar-like oscillators

We aim to detect and characterise solar-like oscillations in bright naked-eye (V<6) main-sequence (MS) and subgiant stars observed by TESS. We seek to expand the current benchmark sample of oscillators, provide accurate global asteroseismic parameters for these bright targets, and assess their potential for future detailed investigations -- including missions such as the HWO and PLATO. Our sample of bright stars was selected from the Hipparcos/Tycho catalogues. We analysed TESS 120-s and 20-s cadence photometry using SPOC light curves and custom apertures from target pixel files. After applying a filtering of the light curves, we extracted global asteroseismic parameters ($ν_{\rm max}$ and $Δν$) using the pySYD pipeline. Results were cross-validated with independent pipelines and compared to predictions from the ATL, while noise properties were evaluated to quantify improvements from a 20-s observing cadence. We detect solar-like oscillations in a total of 196 stars -- including 128 new detections -- with extracted $ν_{\rm max}$ and $Δν$ values showing strong conformity to expected scaling relations. This corresponds to an increase by more than an order of magnitude in the number of MS stars with detection of solar-like oscillations from TESS. Nearly 40% of our new detections are prime HWO targets, enabling systematic asteroseismic age determinations relevant for interpreting atmospheric biosignatures. Our analysis confirms that 20-s cadence data yields lower high-frequency noise levels compared to 120-s data. Moreover, the precise stellar parameters obtained through asteroseismology establish these bright stars as benchmarks for seismic investigations and provide useful constraints for refining stellar evolution models and for complementary analyses in interferometry, spectroscopy, and exoplanet characterisation.

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arXiv2025

Asteroseismology of the G8 subgiant beta Aquilae with SONG-Tenerife, SONG-Australia and TESS

We present time-series radial velocities of the G8 subgiant star beta Aql obtained in 2022 and 2023 using SONG-Tenerife and, for the first time, SONG-Australia. We also analyse a sector of TESS photometry that overlapped with the 2022 SONG data. The resulting power spectrum clearly shows solar-like oscillations centred at 430 muHz. The TESS light curve shows the oscillations at lower signal-to-noise, reflecting the fact that photometric measurements are much more affected by the granulation background than are radial velocities. The simultaneous observations in velocity and photometry represent the best such measurements for any star apart from the Sun. They allowed us to measure the ratio between the bolometric photometric amplitude and the velocity amplitude to be 26.6 +/- 3.1 ppm/(m/s). We measured this ratio for the Sun from published SOHO data to be 19.5 +/- 0.7 ppm/(m/s) and, after accounting for the difference in effective temperatures of and the Sun, these values align with expectations. In both the Sun and beta Aql, the photometry-to-velocity ratio appears to be a function of frequency. We also measured the phase shift of the oscillations in beta Aql between SONG and TESS to be -113 +/- 7 deg, which agrees with the value for the Sun and also with a 3-D simulation of a star with similar properties to beta Aql. Importantly for exoplanet searches, we argue that simultaneous photometry can be used to predict the contribution of oscillations to radial velocities. We measured frequencies for 22 oscillation modes in beta Aql and carried out asteroseismic modelling, yielding an excellent fit to the frequencies. We derived accurate values for the mass and age, and were able to place quite strong constraints on the mixing-length parameter. Finally, we show that the oscillation properties of beta Aql are very similar to stars in the open cluster M67.

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arXiv2025

Modeling Asteroseismic Yields for the Roman Galactic Bulge Time-Domain Survey

The Galactic Bulge Time Domain Survey (GBTDS) of the Roman Space Telescope will take high cadence data of the Galactic bulge. We investigate the asteroseismic potential of this survey for red giants. We simulate the detectability of global asteroseismic frequencies, $ν_{\mathrm{max}}$ and $Δν$, by modify ing Kepler data to match nominal GBTDS observing strategies, considering different noise models, observing cadences, and detection algorithms. Our baseline case, using conservative assumptions, consistently leads to asteroseismic $ν_{\mathrm{max}}$ detection probabilities above 80% for red clump and red giant branch stars brighter than 16th magnitude in Roman's F146 filter. We then inject these detection probabilities into a Galaxia model of the bulge to estimate asteroseismic yields. For our nominal case, we detect 290,000 stars in total, with 185,000 detections in the bulge. Different assumptions give bulge yields from 135,000 to 349,000 stars. For stars with measured $ν_{\mathrm{max}}$, we find that we can recover $Δν$ in 21% to 42% of red clump stars, and 69% to 92% of RGB stars. Implications for survey strategy and asteroseismic population studies are discussed more.

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arXiv2025

Time-resolved p-mode oscillations for subgiant HD 142091 with NEID at WIYN

Detections of Earth-analog planets in radial velocity observations are limited by stellar astrophysical variability occurring on a variety of timescales. Current state-of-the-art methods to disentangle potential planet signals from intrinsic stellar signals assume that stellar signals introduce asymmetries to the line profiles that can therefore be separated from the pure translational Doppler shifts of planets. Here, we examine this assumption using a time series of resolved stellar p-mode oscillations in HD 142091 ($κ$ CrB), as observed on a single night with the NEID spectrograph at 2-minute cadence and with 25 cm/s precision. As an evolved subgiant star, this target has p-mode oscillations that are larger in amplitude (4-8 m/s) and occur on longer timescales (80 min.) than those of typical Sun-like stars of RV surveys, magnifying their corresponding effects on the stellar spectral profile. We show that for HD 142091, p-mode oscillations manifest primarily as pure Doppler shifts in the average line profile -- measured by the cross-correlation function (CCF) -- with "shape-driven" CCF variations as a higher-order effect. Specifically, we find that the amplitude of the shift varies across the CCF bisector, with 10% larger oscillation amplitudes closer to the core of the CCF, and 25% smaller oscillation amplitudes for bisector velocities derived near the wings; we attribute this trend to larger oscillation velocities higher in the stellar atmosphere. Using a line-by-line analysis, we verify that a similar trend is seen as a function of average line depth, with deeper lines showing larger oscillation amplitudes. Finally, we find no evidence that p-mode oscillations have a chromatic dependence across the NEID bandpass beyond that due to intrinsic line depth differences across the spectrum.

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arXiv2025

Enhanced magnetic activity in rapidly rotating binary stars

Stellar activity is fundamental to stellar evolution and the formation and habitability of exoplanets. The interaction between convective motions and rotation in cool stars results in a dynamo process that drives magnetic surface activity. In single stars, activity increases with rotation rate until it saturates for stars with rotation periods Prot < 3 - 10 d. However, the mechanism responsible for saturation remains unclear. Observations indicate that red giants in binary systems that are in spin-orbit resonance exhibit stronger chromospheric activity than single stars with similar rotation rates, suggesting that tidal flows can influence surface activity. Here, we investigate the chromospheric activity of main-sequence binary stars to understand the impact of tidal forces on saturation phenomena. For binaries with 0.5 < Prot/d < 1, mainly contact binaries that share a common thermal envelope, we find enhanced activity rather than saturation. This result supports theoretical predictions that a large-scale $α$ - $ω$ dynamo during common-envelope evolution can generate strong magnetic fields. We also observe supersaturation in chromospheric activity, a phenomenon tentatively noted previously in coronal activity, where activity levels fall below saturation and decrease with shorter rotation periods. Our findings emphasise the importance of studying stellar activity in stars with extreme properties compared to the Sun's.

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arXiv2025

Acoustic modes in M67 cluster stars trace deepening convective envelopes

Acoustic oscillations in stars are sensitive to stellar interiors. Frequency differences between overtone modes -- large separations -- probe stellar density, while differences between low-degree modes -- small separations -- probe the sound speed gradient in the energy-generating core of main sequence Sun-like stars, and hence their ages. At later phases of stellar evolution, characterised by inert cores, small separations are believed to lose much of their power to probe deep interiors and simply become proportional to large separations. Here, we present clear evidence of a rapidly evolving convective zone as stars evolve from the subgiant phase into red giants. By measuring acoustic oscillations in 27 stars from the open cluster M67, we observe deviations of proportionality between small and large separations, which are caused by the influence of the bottom of the convective envelope. These deviations become apparent as the convective envelope penetrates deep into the star during subgiant and red giant evolution, eventually entering an ultra-deep regime that leads to the red giant branch luminosity bump. The tight sequence of cluster stars, free of large spreads in ages and fundamental properties, is essential for revealing the connection between the observed small separations and the chemical discontinuities occurring at the bottom of the convective envelope. We use this sequence to show that combining large and small separations can improve estimations of the masses and ages of field stars well after the main sequence.

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arXiv2025

K-dwarf Radius Inflation and a 10-Gyr Spin-down Clock Unveiled through Asteroseismology of HD 219134 from the Keck Planet Finder

We present the first asteroseismic analysis of the K3\,V planet host HD~219134, based on four consecutive nights of radial velocities collected with the Keck Planet Finder. We applied Gold deconvolution to the power spectrum to disentangle modes from sidelobes in the spectral window, and extracted 25 mode frequencies with spherical degrees $0\leq\ell\leq3$. We derive the fundamental properties using five different evolutionary-modeling pipelines and report a mass of 0.763 $\pm$ 0.020 (stat) $\pm$ 0.007 (sys) M$_\odot$, a radius of 0.748 $\pm$ 0.007 (stat) $\pm$ 0.002 (sys) R$_\odot$, and an age of 10.151 $\pm$ 1.520 (stat) $\pm$ 0.810 (sys) Gyr. Compared to the interferometric radius 0.783 $\pm$ 0.005~R$_\odot$, the asteroseismic radius is 4\% smaller at the 4-$σ$ level -- a discrepancy not easily explained by known interferometric systematics, modeling assumptions on atmospheric boundary conditions and mixing lengths, magnetic fields, or tidal heating. HD~219134 is the first main-sequence star cooler than 5000~K with an asteroseismic age estimate and will serve as a critical calibration point for stellar spin-down relations. We show that existing calibrated prescriptions for angular momentum loss, incorporating weakened magnetic braking with asteroseismically constrained stellar parameters, accurately reproduce the observed rotation period. Additionally, we revised the masses and radii of the super-Earths in the system, which support their having Earth-like compositions. Finally, we confirm that the oscillation amplitude in radial velocity scales as $(L/M)^{1.5}$ in K dwarfs, in contrast to the $(L/M)^{0.7}$ relation observed in G dwarfs. These findings provide significant insights into the structure and angular momentum loss of K-type stars.

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arXiv2025

Asteroseismic Study of Subgiants and Giants of the Open Cluster M67 using Kepler/K2: Expanded Sample and Precise Masses

Sparked by the asteroseismic space revolution, ensemble studies have been used to produce empirical relations linking observed seismic properties and fundamental stellar properties. Cluster stars are particularly valuable because they have the same metallicity, distance, and age, thus reducing scatter to reveal smoother relations. We present the first study of a cluster that spans the full evolutionary sequence from subgiants to core helium-burning red giants using asteroseismology to characterise the stars in M67, including a yellow straggler. We use Kepler/K2 data to measure seismic surface gravity, examine the potential influence of core magnetic fields, derive an empirical expression for the seismic surface term, and determine the phase term $ε$ of the asymptotic relation for acoustic modes, extending its analysis to evolutionary states previously unexplored in detail. Additionally, we calibrate seismic scaling relations for stellar mass and radius, and quantify their systematic errors if surface term corrections are not applied to state-of-the-art stellar models. Our masses show that the Reimers mass loss parameter can not be larger than $η$ $\sim$ 0.23 at the 2-$σ$ level. We use isochrone models designed for M67 and compare their predictions with individual mode frequencies. We find that the seismic masses for subgiants and red giant branch stars align with the isochrone-predicted masses as per their luminosity and colour. However, our results are inconsistent with the mass of one of the stellar components of an eclipsing binary system near the TAMS. We use traditional seismic $χ^2$ fits to estimate a seismic cluster age of 3.95 $\pm$ 0.35 Gyrs.

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