HR: 1330h
AN: SP13A-04    [Abstracts]
TI: How Well do the Oscillation Frequencies Track the Activity ?
AU: * Tripathy, S C
EM: sushant@nso.edu
AF: National Solar Observatory, 950 N Cherry Avenue, Tucson, AZ 85719 United States
AU: Leibacher, J W
EM: leib@nso.edu
AF: National Solar Observatory, 950 N Cherry Avenue, Tucson, AZ 85719 United States
AB: Variations of solar oscillation frequencies with the solar cycle at both low and intermediate degrees are now well established. This is manifested by an increase in frequencies of the modes from minimum to maximum of the activity cycle. It is also known that the shifts are strongly correlatd with different activity indices on time scales of 72 and 108 days for MDI and GONG data respectively. However, earlier results from cycle 22 indicated that the frequencies change over shorter periods of weeks to months. It is therefore interesting to analyse mode frequencies and other mode parameters from time series of shorter duration. Here, we present results from an analysis where the frequencies are computed from 36 and 108 days long time series; the time series being shifted by three days over a period of about 5 months. The frequencies calculated from the 36 day long time series are much better correlated with the activity indices.
DE: 7500 SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY
DE: 7522 Helioseismology
DE: 7524 Magnetic fields
SC: Solar Physics Division - AAS [SP]
MN: 2005 Joint Assembly