Abstract
The low l solar acoustic spectrum has been measured with great accuracy (Δv/v ∼ 10−4), for intermediate radial order modes, 11 ≤ n ≤ 34 (Jiménez et al., 1986; Grec, Fossat, and Pomerantz, 1983; Pallé et al., 1986). The measurement of the frequencies of modes of lower n, up to the fundamental one, are very important as they depart from asymptotic behaviour and, therefore, put more severe constraints on solar models. However, their amplitudes are very low (under 2 cm s−1) and when compared to the solar velocity background noise (Jiménez et al., 1986), a S/N ∼ 1 is obtained. Taking advantage of the fact that lifetimes seem to be higher at lower frequencies (lower n values) (Jefferies et al., 1988; Elsworth et al., 1990), very long Doppler velocity measurements, obtained at Teide Observatory, have been used to increase S/N, therefore, providing the possibility to detect such modes. The frequencies observed are compared to those predicted by a solar model (Christensen-Dalsgaard, Däppen, and Lebreton, 1988), using the best equation of state yet computed (Mihalas, Däppen, and Hummer, 1988).
Similar content being viewed by others
References
Bahcall, J. N. and Ulrich, R. K.: 1988, Rev. Mod. Phys. 60, 297.
Brookes, J. R., Isaak, G. R., and van der Raay, H. B.: 1978, Monthly Notices Roy. Astron. Soc. 185, 1.
Christensen-Dalsgaard, J.: 1982, Monthly Notices Roy. Astron. Soc. 199, 735.
Christensen-Dalsgaard, J. and Demarque, P.: 1989, GONG Newsletter 11.
Christensen-Dalsgaard, J., Däppen, W., and Lebreton, Y.: 1988, Nature 336, 634.
Claverie, A., Isaak, G. R., van der Raay, H. B., and Roca Cortés, T.: 1981, Nature 293, 443.
Cox, A. N. and Tabor, J. E.: 1976, Astrophys. J. Suppl. 31, 271.
Cox, A. N., Guzik, J. A., and Kidman, R. B.: 1989, Astrophys. J. 342, 1187.
Elsworth, Y., Isaak, G. R., Jefferies, S. M., McLeod, C. P., New, R., Pallé, P. L., Régulo, C., and Roca Cortés, T.: 1990, Monthly Notices Roy. Astron. Soc. 242, 135.
Grec, G., Fossat, E., and Pomerantz, M. A.: 1983, Solar Phys. 82, 55.
Huebner, W. F., Merts, A. L., Magee, N. H., and Argo, M. F.: 1977, Astrophysical Opacity Library, Los Alamos Scientific Laboratory Report LA-6760-M.3.
Isaak, G. R., van der Raay, H. B., Pallé, P. L., Roca Cortés, T., and Delache, P.: 1984, Mem. Soc. Astron. Ital. 55, 91.
Jefferies, S. M., Pallé, P. L., van der Raay, H. B., Régulo, C., and Roca Cortés, T.: 1988, Nature 333, 646.
Jiménez, A., Pallé, P. L., Pérez Hernández, F., Régulo, C., and Roca Cortés, T.: 1986, Astron. Astrophys. 192, L7.
Jiménez, A., Pallé, P. L., Régulo, C., Roca Cortés, T., Isaak, G. R., McLeod, C. P., and van der Raay, H. B.: 1988, in J. Christensen-Dalsgaard and S. Frandsen (eds.), ‘Advances in Helio- and Asteroseismology’, IAU Symp. 123.
Libbrecht, K.: 1988, in E. Rolfe (ed.), Seismology of the Sun and Sun-Like Stars, ESA SP-286, p. 3.
Mihalas, D., Däppen, W., and Hummer, D. G.: 1988, Astrophys. J. 331, 815.
Pallé, P. L.: 1986, Ph.D. Thesis, Universidad de La Laguna.
Pallé, P. L. and Roca Cortés, T.: 1988, in J. Christensen-Dalsgaard and S. Frandsen (eds.), ‘Advances in Helio- and Asteroseismology’, IAU Symp. 123, 79.
Pallé, P. L., Régulo, C., and Roca Cortés, T.: 1988, in E. Rolfe (ed.), Seismology of the Sun and Sun-Like Stars, ESA SP-286, p. 285.
Pallé, P. L., Régulo, C., and Roca Cortés, T.: 1989, Astron. Astrophys. 224, 253.
Pallé, P. L., Pérez, J. C., Régulo, C., Roca Cortés, T., Isaak, G. R., McLeod, C. P., and van der Raay, H. B.: 1986, Astron. Astrophys. 169, 313.
van der Raay, H. B.: 1988, in E. Rolfe (ed.), Seismology of the Sun and Sun-Like Stars, ESA SP-286, p. 339.
van der Raay, H. B., Pallé, P. L., and Roca Cortés, T.: 1985, in D. O. Gough (ed.), Seismology of the Sun and Distant Stars, Vol. 169, p. 333.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Anguera Gubau, M., Pallé, P.L., Pérez Hernández, F. et al. An attempt to identify low l - low n solar acoustic modes. Sol Phys 128, 79–90 (1990). https://doi.org/10.1007/BF00154149
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00154149