160-min pulsation of the Sun: New observational results

✍ Scribed by V. A. Kotov; T. T. Tsap; V. I. Haneychuk

• Book ID: 104643081
• Publisher: Springer
• Year: 1991
• Tongue: English
• Weight: 421 KB
• Volume: 133
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00149829

✦ Synopsis

The 1974-I988 Crimean measurements of the solar line-of-sight velocity continue to show the presence of a statistically significant periodicity Po -160.009 ( _+ 1) rain with an average harmonic amplitude of about 21 cm s-~. The period is supposed to be that of the global pulsation of the Sun but with a little-known physical mechanism of excitation.

The new observations give some evidence for the existence of a second periodicity, P1 = 160.014(_+ 1)rain. It is hypothesized that the appearance of P1 might be a sidelobe mode (of the Po-oscillation) induced by rapid rotation of the central solar core.

It is also noted that the spacing, in frequency, between Po and P1 corresponds to a beat period of 10 _+ 3 yr, which happens to be in good agreement with the average duration of the 11 yr cycle &the magnetic activity of the Sun. Accordingly, we suppose that the phase shift of the P0-mode between the 1974-1982 and 1986-1988 time intervals reflects a remarkable change of the general magnetic field of the Sun in the course of the 22 yr solar cycle.