Asteroseismology from multi-month<i>Kepler</i>photometry: the evolved Sun-like stars KIC 10273246 and KIC 10920273

Campante, Tiago L.; Handberg, R.; Mathur, S.; Appourchaux, T.; Bedding, Timothy R.; Chaplin, W. J.; García, R. A.; Mosser, B.; Benomar, O.; Bonanno, A.; Corsaro, E.; Fletcher, S.M.; Gaulme, P.; Hekker, S.; Karoff, C.; Régulo, C.; Salabert, D.; Verner, G. A.; White, T. R.; Houdek, G.; Brandão, I. M.; Creevey, O.; Doğan, G.; Bazot, M.; Christensen‐Dalsgaard, J.; Cunha, M. S.; Elsworth, Y.; Huber, Daniel; Kjeldsen, H.; Lundkvist, M.; Molenda-Żakowicz, J.; Monteiro, M. J. P. F. G.; Stello, Dennis; Clarke, Bruce; Girouard, Forrest R.; Hall, Jennifer R.

doi:10.1051/0004-6361/201116620

Cited by 84 publications

(107 citation statements)

References 89 publications

(96 reference statements)

Supporting

Mentioning

102

Contrasting

Order By: Relevance

“…In this case the uncertainties in log g, R, and M for C5 reduce by a factor of three. (d) P ROTest as reported by Campante et al (2011) and Mathur et al (2011), with uncertainties in parenthesis. …”

Section: Discussionmentioning

confidence: 99%

“…Campante et al (2011) andMathur et al (2011) study the low frequency range of the power spectra and estimate rotational periods of 36, 23, and 27 days for C1, C2, and C3, respectively. Adopting these as P ROT constrains the stellar inclination angle i = 20 •+18 −15 for C1, i = 44 •+46 −23 for C2, and i = 25 •+65 −20 for C3.…”

Section: Notesmentioning

confidence: 99%

“…For the metal-rich star C1, however, the relatively high Li abundance indicates a non-evolved MS star, while the asteroseismic analysis suggests an incompatible value of ∼4 Gyr. Campante et al (2011) and Mathur et al (2011) analysed the time series and presented the oscillation frequencies for C1, C2, C3, and C5. Using the individual frequencies will yield more precise stellar properties, as well as studies of the stellar interior (Brandão et al 2012, Dogan et al 2012 as shown by Metcalfe et al (2010).…”

Section: Notesmentioning

confidence: 99%

See 2 more Smart Citations

Fundamental properties of fiveKeplerstars using global asteroseismic quantities and ground-based observations

Creevey

Doğan

Frasca

et al. 2012

A&A

Self Cite

View full text Add to dashboard Cite

We present an asteroseismic study of the solar-like stars KIC 11395018, KIC 10273246, KIC 10920273, KIC 10339342, and KIC 11234888 using short-cadence time series of more than eight months from the Kepler satellite. For four of these stars, we derive atmospheric parameters from spectra acquired with the Nordic Optical Telescope. The global seismic quantities (average large frequency separation and frequency of maximum power), combined with the atmospheric parameters, yield the mean density and surface gravity with precisions of 2% and ∼0.03 dex, respectively. We also determine the radius, mass, and age with precisions of 2-5%, 7-11%, and ∼35%, respectively, using grid-based analyses. Coupling the stellar parameters with photometric data yields an asteroseismic distance with a precision better than 10%. A v sin i measurement provides a rotational period-inclination correlation, and using the rotational periods from the recent literature, we constrain the stellar inclination for three of the stars. An Li abundance analysis yields an independent estimate of the age, but this is inconsistent with the asteroseismically determined age for one of the stars. We assess the performance of five grid-based analysis methods and find them all to provide consistent values of the surface gravity to ∼0.03 dex when both atmospheric and seismic constraints are at hand. The different grid-based analyses all yield fitted values of radius and mass to within 2.4σ, and taking the mean of these results reduces it to 1.5σ. The absence of a metallicity constraint when the average large frequency separation is measured with a precision of 1% biases the fitted radius and mass for the stars with non-solar metallicity (metal-rich KIC 11395018 and metal-poor KIC 10273246), while including a metallicity constraint reduces the uncertainties in both of these parameters by almost a factor of two. We found that including the average small frequency separation improves the determination of the age only for KIC 11395018 and KIC 11234888, and for the latter this improvement was due to the lack of strong atmospheric constraints.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Notesmentioning

confidence: 99%

Section: Notesmentioning

confidence: 99%

See 1 more Smart Citation

Fundamental properties of fiveKeplerstars using global asteroseismic quantities and ground-based observations

Creevey

Doğan

Frasca

et al. 2012

A&A

Self Cite

View full text Add to dashboard Cite

show abstract

“…They were first detected from the ground (Kjeldsen et al 1995). More recently, with the advent of space missions CoRoT (Baglin et al 2006) and Kepler (Borucki et al 2010), mixed modes were detected in thousands of subgiants (Deheuvels et al 2010;Campante et al 2011) and red giants (Bedding et al 2011;Mosser et al 2011). The measurement of rotational splittings of mixed modes (Beck et al 2012;Deheuvels et al 2012;Mosser et al 2012) has given direct insight into the internal rotation of red giants and their variations with evolution.…”

Section: Introductionmentioning

confidence: 99%

Near-degeneracy effects on the frequencies of rotationally-split mixed modes in red giants

Deheuvels

Ouazzani

Basu

2017

A&A

View full text Add to dashboard Cite

Context. The Kepler space mission has made it possible to measure the rotational splittings of mixed modes in red giants, thereby providing an unprecedented opportunity to probe the internal rotation of these stars. Aims. Asymmetries have been detected in the rotational multiplets of several red giants. This is unexpected since all the red giants whose rotation profiles have been measured thus far are found to rotate slowly, and low rotation, in principle, produces symmetrical multiplets. Our aim here is to explain these asymmetries and find a way of exploiting them to probe the internal rotation of red giants. Methods. We show that in the cases where asymmetrical multiplets were detected, near-degeneracy effects are expected to occur, because of the combined effects of rotation and mode mixing. Such effects have not been taken into account so far. By using both perturbative and non-perturbative approaches, we show that near-degeneracy effects produce multiplet asymmetries that are very similar to the observations. We then propose and validate a method based on the perturbative approach to probe the internal rotation of red giants using multiplet asymmetries. Results. We successfully apply our method to the asymmetrical l = 2 multiplets of the Kepler young red giant KIC 7341231 and obtain precise estimates of its mean rotation in the core and the envelope. The observed asymmetries are reproduced with a good statistical agreement, which confirms that near-degeneracy effects are very likely the cause of the detected multiplet asymmetries. Conclusions. We expect near-degeneracy effects to be important for l = 2 mixed modes all along the red giant branch (RGB). For l = 1 modes, these effects can be neglected only at the base of the RGB. They must therefore be taken into account when interpreting rotational splittings and as shown here, they can bring valuable information about the internal rotation of red giants.

show abstract

“…While we have followed the fitting strategy used in previous analyses of single stars (e.g. Campante et al 2011;Mathur et al 2011Mathur et al , 2013Appourchaux et al 2012), extra care was required to ensure a correct fit of the power spectrum. Initial values for the mode frequencies were obtained by scaling the solar p-mode frequencies measured by BiSON (Broomhall et al 2009).…”

Section: Mode Parametersmentioning

confidence: 99%

Keplerobservations of the asteroseismic binary HD 176465

White

Benomar

Aguirre

et al. 2017

A&A

Self Cite

View full text Add to dashboard Cite

Binary star systems are important for understanding stellar structure and evolution, and are especially useful when oscillations can be detected and analysed with asteroseismology. However, only four systems are known in which solar-like oscillations are detected in both components. Here, we analyse the fifth such system, HD 176465, which was observed by Kepler. We carefully analysed the system's power spectrum to measure individual mode frequencies, adapting our methods where necessary to accommodate the fact that both stars oscillate in a similar frequency range. We also modelled the two stars independently by fitting stellar models to the frequencies and complementary parameters. We are able to cleanly separate the oscillation modes in both systems. The stellar models produce compatible ages and initial compositions for the stars, as is expected from their common and contemporaneous origin. Combining the individual ages, the system is about 3.0 ± 0.5 Gyr old. The two components of HD 176465 are young physicallysimilar oscillating solar analogues, the first such system to be found, and provide important constraints for stellar evolution and asteroseismology.

show abstract

Asteroseismology from multi-monthKeplerphotometry: the evolved Sun-like stars KIC 10273246 and KIC 10920273

Cited by 84 publications

References 89 publications

Fundamental properties of fiveKeplerstars using global asteroseismic quantities and ground-based observations

Fundamental properties of fiveKeplerstars using global asteroseismic quantities and ground-based observations

Near-degeneracy effects on the frequencies of rotationally-split mixed modes in red giants

Keplerobservations of the asteroseismic binary HD 176465

Contact Info

Product

Resources

About