Solar cycle variations of oscillation mode parameters from LOWL and MARK-I instruments

Jimeńez Reyes, S. J.; Corbard, T.; Tomczyk, S.; Pallé, P. L.
Bibliographical reference

American Astronomical Society, SPD Meeting #31, #01.12; Bulletin of the American Astronomical Society, Vol. 32, p.1289

Advertised on:
10
2000
Number of authors
4
IAC number of authors
1
Citations
0
Refereed citations
0
Description
The signature of the Solar-Cycle appears clearly in the p-mode parameters (Jiménez-Reyes et al. 1998, Libbrecht & Woodard 1990, and Anguera et al. 1992). At present, the study of the p-mode parameter variation is a very active topic in helioseismology where, thanks to projects like BISON, IRIS, GONG, LOWL and MDI, we are able for the first time to analyse, using heliosismology, how the Sun internal structure and dynamic change over the magnetic cycle. High-quality observations for low degree p-modes have been accumulated for more than twenty years using the solar spectro photometer MARK-I, located and operating at the Observatorio del Teide (Tenerife, Spain). The data-base available have been re-analyzed over a much wider time interval than before. Moreover, the LOWL instrument, a Potassium Magneto-Optical Filter, located at the Manua Loa Observatory, has been measuring for more than six years solar oscillations of intermadiate p-mode degree. The data-base represents one of the best available to analyze the influence of the Solar-Cycle on the mode parameters, mainly because these data, concerning both low and intermadiate degree modes, give us information over an extensive range of the solar depths which may allow us to locate characteristics of the solar dynamo process. Using different data sets and different techniques, we analyse the behaviour of the solar p-modes in an attempt to better understand the origin of the Solar-Cycle.