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:

Shallow mixing in the solar photosphere inferred from revised beryllium abundances

Nature volume 392, pages 791–793 (1998)Cite this article

Abstract

The chemical compositions of the Sun and meteorites are the benchmarks against which the abundances of elements in all other astronomical objects are compared. A long-standing problem1 has been the abundance of lithium in the Sun's photosphere, which is ∼140 times less than the meteoritic value (which represents the lithium abundance at the time the Solar System formed). This depletion requires that material from the photosphere be transported below the convective zone into regions where the temperature is high enough that nuclear processing can remove lithium. The models2,3 best able to do so simultaneously deplete beryllium by about a factor of two, which is consistent with previous measurements4,5 of the beryllium abundance in the solar photosphere. But here we show that these previous measurements are in error, because they did not fully account for the continuous opacity in the ultraviolet region of the spectrum where the beryllium lines are observed. We find that, after correcting for this opacity, solar beryllium is not depleted at all with respect to the meteoritic value. This implies that mixing in the solar photosphere is more superficial than had hitherto been supposed, consistent with the shallow mixing inferred from recent helioseismic data6.

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: The solar flux spectrum13 around one clean OH feature (solid line) compared to calculated spectra (dotted lines).
Figure 2: The Be II region in the solar flux spectrum13 (solid line) compared to calculated spectra (dotted lines).

Similar content being viewed by others

References

  1. Pinsonneault, M. H. Mixing in stars. Annu. Rev. Astron. Astrophys. 35, 557–605 (1997).

    Article  ADS  CAS  Google Scholar 

  2. Pinsonneault, M. H., Kawaler, S. D., Sofia, S. & Demarque, P. Evolutionary models of the rotating sun. Astrophys. J. 338, 424–452 (1989).

    Article  ADS  CAS  Google Scholar 

  3. Richard, O., Vauclair, S., Charbonnel, C. & Dziembowski, W. A. New solar models including helioseismological constrains and light-element depletion. Astron. Astrophys. 312, 1000–1011 (1996).

    ADS  CAS  Google Scholar 

  4. King, J. R., Deliyannis, C. P. & Boesgaard, A. M. The 9Be abundances of alpha centauri A and B and the sun: Implications for stellar evolution and mixing. Astrophys. J. 478, 778–786 (1997).

    Article  ADS  CAS  Google Scholar 

  5. Primas, F., Duncan, D. K., Pinsonneault, M. H., Deliyannis, C. P. & Thorburn, J. A. Hubble Space Telescope beryllium abundances in the alpha centauri system. Astrophys. J. 480, 784–793 (1997).

    Article  ADS  CAS  Google Scholar 

  6. Basu, S. Seismology at the base of the solar convective zone. Mont. Not. R. Astron. Soc. 288, 572–584 (1997).

    Article  ADS  Google Scholar 

  7. Gustafsson, B. & Bell, R. A. The colours of G and K type giant stars. I. Astron. Astrophys. 74, 313–352 (1979).

    ADS  CAS  Google Scholar 

  8. Kurucz, R. L. Finding the “missing” solar ultraviolet opacity. Rev. Mex. Astron. Astrofis. 23, 181–194 (1992).

    ADS  CAS  Google Scholar 

  9. Bell, R. A., Paltoglou, G. & Tripicco, M. J. The calibration of synthetic colours. Mon. Not. R. Astron. Soc. 268, 771–792 (1994).

    Article  ADS  CAS  Google Scholar 

  10. Holweger, H. Depression of the solar continuous spectrum by line absorption and Balmer continuum. Astron. Astrophys. 4, 11–17 (1970).

    ADS  CAS  Google Scholar 

  11. Grevesse, N. & Sauval, A. J. in Molecules in the Stellar Environment (ed. Jorgensen, U. G.) 196–208 (IAU Colloq. 146, Springer, Berlin, 1994).

    Book  Google Scholar 

  12. Bauschlicher, C. W. J & Langhoff, S. R. Theoretical determination of the radiative lifetime of the A2Σ+ state of OH. J. Chem. Phys. 87, 4665–4672 (1987).

    Article  ADS  CAS  Google Scholar 

  13. Kurucz, R. L., Furenlid, I., Brault, J. & Testerman, L. Solar Flux Atlas from 296 to 1200 nanometers (Natl Solar Observatory, Tucson, 1984).

    Google Scholar 

  14. Holweger, H. & Müller, E. A. The photospheric barium spectrum — Solar abundance and collisional broadening of Ba II lines by hydrogen. Solar Phys. 39, 19–30 (1974).

    Article  ADS  CAS  Google Scholar 

  15. Kurucz, R. L. Atlas 9 Stellar Atmosphere Programs and 2em/s Grid CD-ROM No. 13(Smithsonian Astrophys. Observatory, 1993).

    Google Scholar 

  16. Edvardsson, B. et al. The chemical evolution of the galactic disk — part one — analysis and results. Astron. Astrophys. 275, 101–152 (1993).

    ADS  CAS  Google Scholar 

  17. Grevesse, N., Sauval, A. J. & van Dischoeck, E. F. An analysis of vibration-rotation lines of OH in the solar infrared spectrum. Astron. Astrophys. 141, 10–16 (1984).

    ADS  CAS  Google Scholar 

  18. Seaton, M. J., Yan, Y., Mihalas, D. & Pradhan, A. K. Opacities for stellar envelopes. Mon. Not. R. Astron. Soc. 266, 805–828 (1994).

    Article  ADS  CAS  Google Scholar 

  19. Dragon, J. N. & Mutschlecner, J. P. The Solar Ultraviolet Continuum. Astrophys. J. 239, 1045–1069 (1980).

    Article  ADS  CAS  Google Scholar 

  20. Kurucz, R. L., van Dischoeck, E. F. & Tarafdar, S. P. OH and CH continuous opacity in solar and stellar atmospheres. Astrophys. J. 322, 992–998 (1987).

    Article  ADS  CAS  Google Scholar 

  21. Chmielewski, Y., Müller, E. A. & Brault, J. W. The solar beryllium abundance. Astron. Astrophys. 42, 37–46 (1975).

    ADS  CAS  Google Scholar 

  22. Woods, T. N. et al. Validation of the UARS solar ultraviolet irradiances: Comparison with the ATLAS1 and 2 measurements. J. Geophys. Res. D6, 9541–9569 (1996).

    Article  ADS  Google Scholar 

  23. Kumar, P. & Quataert, E. J. Angular momentum transport by gravity waves and its effect on the rotation of the solar interior. Astrophys. J. 475, L143–L146 (1997).

    Article  ADS  Google Scholar 

  24. Zahn, J.-P., Talon, S. & Matias, J. Angular momentum transport by internal waves in the solar interior. Astron. Astrophys. 322, 320–328 (1997).

    ADS  Google Scholar 

  25. Stark, G., Brault, J. W. & Abrams, M. C. Fourier-transform spectra of the A2Σ+ − X2II Δν = 0 bands of OH and OD. J. Opt. Soc. Am. B 11, 3–32 (1994).

    Article  ADS  CAS  Google Scholar 

  26. Goldman, A. & Gillis, J. R. Spectral line parameters for the A2Σ+ − X2II(0,0) band of OH for atmospheric and high temperatures. J. Quant. Spectrosc. Radiat. Transfer 25, 111–135 (1981).

    Article  ADS  CAS  Google Scholar 

  27. German, K. R. Direct measurement of the radiative lifetimes of the A2Σ+ (V′ = 0) states of OH and OD. J. Chem. Phys. 62, 2584–2587 (1974).

    Article  ADS  Google Scholar 

  28. Wiese, W. L. & Martin, G. A. Wavelengths and Transition Probabilities for Atoms and Atomic Ions (NBS Monogr. 68, US Govt Print. Off., Washington, DC, 1980).

    Google Scholar 

  29. García López, R. J., Severino, G. & Gomez, M. T. Galactic evolution of beryllium. I. NLTE effects and accuracy of beryllium abundances in metal-poor stars. Astron. Astrophys. 297, 787–801 (1995).

    ADS  Google Scholar 

  30. Kiselman, D. & Carlsson, M. in The Light Element Abundances (ed. Crane, P.) 372–381 (Proc. ESO/EPIC Workshop, Springer, Berlin, 1995).

    Book  Google Scholar 

Download references

Acknowledgements

We thank C. Proffitt and D. Lambert for discussion. This work was supported by a NASA grant to S.C.B. and a NSF grant to R.A.B.

Author information

Authors and Affiliations

  1. Department of Astronomy, University of Maryland, College Park, 20742, Maryland, USA

    Suchitra C. Balachandran & Roger A. Bell

Authors
  1. Suchitra C. Balachandran
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Roger A. Bell
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Suchitra C. Balachandran.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Balachandran, S., Bell, R. Shallow mixing in the solar photosphere inferred from revised beryllium abundances. Nature 392, 791–793 (1998). https://doi.org/10.1038/33879

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/33879

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