Identification of solar acoustic modes of low angular degree and low radial order

Citation
L. Bertello et al., Identification of solar acoustic modes of low angular degree and low radial order, ASTROPHYS J, 537(2), 2000, pp. L143-L146
Citations number
26
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICAL JOURNAL
ISSN journal
0004637X → ACNP
Volume
537
Issue
2
Year of publication
2000
Part
2
Pages
L143 - L146
Database
ISI
SICI code
0004-637X(20000710)537:2<L143:IOSAMO>2.0.ZU;2-S
Abstract
We present evidence for the detection of low radial order (n < 10) acoustic modes of low angular degree, l = 0-2, in the 759 day long Global Oscillati ons at Low Frequency and Michelson Doppler Imager time series. We used Rand om-Lag Singular Cross-Spectrum Analysis, which searches for simultaneous os cillatory components in two or more time series. We have determined II mode s in the range n = 3-9, of which eight modes confirm the previous measureme nts by Toutain et al. and three modes of l = 0 and n = 3, 5, and 6 are reli ably measured for the first time. The errors of frequency determination are also significantly reduced for several previously identified modes. New so und speed inversion results suggest that the effect of inhomogeneous initia l composition of the Sun should be included in the standard solar model.