Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Non-radial oscillation modes with long lifetimes in giant stars

Nature volume 459, pages 398–400 (2009)Cite this article

Abstract

Towards the end of their lives, stars like the Sun greatly expand to become red giant stars. Such evolved stars could provide stringent tests of stellar theory, as many uncertainties of the internal stellar structure accumulate with age. Important examples are convective overshooting and rotational mixing during the central hydrogen-burning phase, which determine the mass of the helium core, but which are not well understood1. In principle, analysis of radial and non-radial stellar oscillations can be used to constrain the mass of the helium core. Although all giants are expected to oscillate2, it has hitherto been unclear whether non-radial modes are observable at all in red giants, or whether the oscillation modes have a short or a long mode lifetime3,4,5,6,7, which determines the observational precision of the frequencies. Here we report the presence of radial and non-radial oscillations in more than 300 giant stars. For at least some of the giants, the mode lifetimes are of the order of a month. We observe giant stars with equally spaced frequency peaks in the Fourier spectrum of the time series, as well as giants for which the spectrum seems to be more complex. No satisfactory theoretical explanation currently exists for our observations.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: A stack of power spectra of nine red giant pulsators.
Figure 2: Power density spectrum of the red giant candidate CoRoT-101034881 showing a frequency pattern with a regular spacing.
Figure 3: Echelle diagram of the modes shown in Fig. 2, showing ‘ridges’ related to radial and non-radial modes.
Figure 4: Power density spectrum of the red giant CoRoT-101600807 showing broad profiles.

Similar content being viewed by others

References

  1. Aerts, C., Christensen-Dalsgaard, J., Cunha, M. & Kurtz, D. W. The current status of asteroseismology. Sol. Phys. 251, 3–20 (2008)

    Article  ADS  Google Scholar 

  2. Dziembowski, W., Gough, D. O., Houdek, G. & Sienkiewicz, R. Oscillations of α UMa and other red giants. Mon. Not. R. Astron. Soc. 382, 601–610 (2001)

    Article  ADS  Google Scholar 

  3. De Ridder, J. et al. Discovery of solar-like oscillations in the red giant ε Ophiuchi. Astron. Astrophys. 448, 689–695 (2006)

    Article  ADS  Google Scholar 

  4. Barban, C. et al. Detection of solar-like oscillations in the red giant star ε Ophiuchi by MOST spacebased photometry. Astron. Astrophys. 468, 1033–1038 (2007)

    Article  ADS  Google Scholar 

  5. Kallinger, T. et al. Nonradial p-modes in the G9.5 giant ε Ophiuchi? Pulsation model fits to MOST photometry. Astron. Astrophys. 478, 497–505 (2008)

    Article  ADS  Google Scholar 

  6. Hekker, S., Aerts, C., De Ridder, J. & Carrier, F. Pulsations detected in the line profile variations of red giants. Modelling of line moments, line bisector and line shape. Astron. Astrophys. 458, 931–940 (2006)

    Article  ADS  Google Scholar 

  7. Stello, D., Kjeldsen, H., Bedding, T. R. & Buzasi, D. Oscillation mode lifetimes in ξ Hydrae: will strong mode damping limit asteroseismology of red giant stars? Astron. Astrophys. 448, 709–715 (2006)

    Article  ADS  Google Scholar 

  8. Edmonds, P. D. & Gilliland, R. L. K giants in 47 Tucanae: Detection of a new class of variable stars. Astrophys. J. 464, L157–L160 (1996)

    Article  ADS  Google Scholar 

  9. Buzasi, D. et al. The detection of multimodal oscillations on α Ursae Majoris. Astrophys. J. 532, L133–L136 (2000)

    Article  ADS  CAS  Google Scholar 

  10. Frandsen, S. et al. Detection of solar-like oscillations in the G7 giant star xi Hya. Astron. Astrophys. 394, L5–L8 (2002)

    Article  ADS  Google Scholar 

  11. Retter, A. et al. Oscillations in Arcturus from WIRE photometry. Astrophys. J. 591, L151–L154 (2003)

    Article  ADS  Google Scholar 

  12. Tarrant, N. J. et al. Asteroseismology of red giants: photometric observations of Arcturus by SMEI. Mon. Not. R. Astron. Soc. Lett. 382, L48–L52 (2007)

    Article  ADS  Google Scholar 

  13. Stello, D. et al. Multisite campaign on the open cluster M67—II. Evidence for solar-like oscillations in red giant stars. Mon. Not. R. Astron. Soc. 377, 584–594 (2007)

    Article  ADS  Google Scholar 

  14. Hatzes, A. P. & Zechmeister, M. The discovery of stellar oscillations in the planet-hosting giant star β Geminorum. Astrophys. J. 670, L37–L40 (2007)

    Article  ADS  Google Scholar 

  15. Stello, D., Bruntt, H., Preston, H. & Buzasi, D. Oscillating K giants with the WIRE satellite: determination of their asteroseismic masses. Astrophys. J. 674, L53–L56 (2008)

    Article  ADS  Google Scholar 

  16. Gilliland, R. L. Photometric oscillations of low-luminosity red giant stars. Astron. J. 136, 566–579 (2008)

    Article  ADS  Google Scholar 

  17. Baglin, A. et al. The CoRoT mission and its scientific objectives. AIP Conf. Proc. 895, 201–209 (2007)

    Article  ADS  Google Scholar 

  18. Pallé, P. L. et al. A measurement of the background solar velocity spectrum. Astrophys. J. 441, 952–959 (1995)

    Article  ADS  Google Scholar 

  19. Kjeldsen, H. & Bedding, T. R. Amplitudes of stellar oscillations: the implications for asteroseismology. Astron. Astrophys. 293, 87–106 (1995)

    ADS  Google Scholar 

  20. Guenther, D. et al. Evolutionary model and oscillation frequencies for α Ursae Majoris: a comparison with observations. Astrophys. J. 530, L45–L48 (2000)

    Article  ADS  CAS  Google Scholar 

  21. Tassoul, M. Asymptotic approximations for stellar nonradial pulsations. Astrophys. J. Suppl. Ser. 43, 469–490 (1980)

    Article  ADS  Google Scholar 

Download references

Acknowledgements

J.D.R., F.C. and S.H. acknowledge support from the Fund for Scientific Research, Flanders, from the research council of K. U. Leuven, and from the Belgian Federal Science Policy. A.P.H. acknowledges the support of the Deutsches Zentrum für Luft- und Raumfahrt. T.K. and W.W.W. acknowledge support by the Austrian Research Promotion Agency (FFG-ARL). J.D.R. thanks A. Miglio, M.-A. Dupret and C. Aerts for discussions.

Author information

Authors and Affiliations

  1. Instituut voor Sterrenkunde, K. U. Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium ,

    Joris De Ridder, Fabien Carrier & Saskia Hekker

  2. LESIA, UMR8109, Université Pierre et Marie Curie, Université Denis Diderot, Observatoire de Paris, 92195 Meudon, France ,

    Caroline Barban, Annie Baglin, Michel Auvergne & Réza Samadi

  3. Institut d’Astrophysique Spatiale, UMR 8617 CNRS-Université Paris XI, Campus d’Orsay, F-91405 Orsay Cedex, France

    Frédéric Baudin

  4. Thüringer Landessternwarte, D-07778 Tautenburg, Germany

    Artie P. Hatzes

  5. Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium ,

    Saskia Hekker

  6. Institute for Astronomy, University of Vienna, Türkenschanzstrasse 17, A-1180 Vienna, Austria ,

    Thomas Kallinger & Werner W. Weiss

  7. Laboratoire d’Astrophysique de Marseille, OAMP, Université Aix-Marseille & CNRS, 38 rue Frédéric Joliot Curie, 13388 Marseille 13, France ,

    Pierre Barge & Magali Deleuil

Authors
  1. Joris De Ridder
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Caroline Barban
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Frédéric Baudin
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Fabien Carrier
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Artie P. Hatzes
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Saskia Hekker
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Thomas Kallinger
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Werner W. Weiss
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Annie Baglin
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Michel Auvergne
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. Réza Samadi
    View author publications

    You can also search for this author in PubMed Google Scholar

  12. Pierre Barge
    View author publications

    You can also search for this author in PubMed Google Scholar

  13. Magali Deleuil
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Joris De Ridder.

Supplementary information

Supplementary Information

This file contains Supplementary Figures 1-4 with Legends, Supplementary Methods, Supplementary Table 1,a Supplementary Discussion, Supplementary Notes and Supplementary References. (PDF 569 kb)

PowerPoint slides

Rights and permissions

Reprints and permissions

About this article

Cite this article

De Ridder, J., Barban, C., Baudin, F. et al. Non-radial oscillation modes with long lifetimes in giant stars. Nature 459, 398–400 (2009). https://doi.org/10.1038/nature08022

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature08022

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing