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Progress report on solar age calibration
| Content Provider | Scilit |
|---|---|
| Author | Houdek, G. Gough, D. O. |
| Copyright Year | 2008 |
| Description | We report on an ongoing investigation into a seismic calibration of solar models designed for estimating the main-sequence age and a measure of the chemical abundances of the Sun. Only modes of low degree are employed, so that with appropriate modification the procedure could be applied to other stars. We have found that, as has been anticipated, a separation of the contributions to the seismic frequencies arising from the relatively smooth, glitch-free, background structure of the star and from glitches produced by helium ionization and the abrupt gradient change at the base of the convection zone renders the procedure more robust than earlier calibrations that fitted only raw frequencies to glitch-free asymptotics. As in the past, we use asymptotic analysis to design seismic signatures that are, to the best of our ability, contaminated as little as possible by those uncertain properties of the star that are not directly associated with age and chemical composition. The calibration itself, however, employs only numerically computed eigenfrequencies. It is based on a linear perturbation from a reference model. Two reference models have been used, one somewhat younger, the other somewhat older than the Sun. The two calibrations, which use BiSON data, are more-or-less consistent, and yield a main-sequence $aget_{⊙}$= 4.68 ± 0.02 Gy, coupled with a formal initial heavy-element abundanceZ= 0.0169 ± 0.0005. The error analysis has not yet been completed, so the estimated precision must be taken with a pinch of salt. |
| Related Links | https://www.cambridge.org/core/services/aop-cambridge-core/content/view/8C7931B463A7781A651E70BBD0A6CF64/S1743921308022692a.pdf/div-class-title-progress-report-on-solar-age-calibration-div.pdf |
| Ending Page | 156 |
| Page Count | 8 |
| Starting Page | 149 |
| ISSN | 17439213 |
| e-ISSN | 17439221 |
| DOI | 10.1017/s1743921308022692 |
| Journal | Proceedings of the International Astronomical Union |
| Issue Number | S252 |
| Volume Number | 4 |
| Language | English |
| Publisher | Cambridge University Press (CUP) |
| Publisher Date | 2008-04-01 |
| Access Restriction | Open |
| Subject Keyword | Proceedings of the International Astronomical Union Astronomy and Astrophysics Helioseismology Abundances Oscillations Fundamental Parameters |
| Content Type | Text |
| Resource Type | Article |
| Subject | Astronomy and Astrophysics Space and Planetary Science |
