Analysis of Ca(+) K plage area for short period variation

dc.contributor.author	Singh, J
dc.contributor.author	Jain, S. K
dc.date.accessioned	2008-09-16T14:11:20Z
dc.date.available	2008-09-16T14:11:20Z
dc.date.issued	1989-12
dc.identifier.citation	Journal of Astrophysics and Astronomy , Vol. 10, No. 4, pp. 381 - 389	en
dc.identifier.issn	0250-6335
dc.identifier.uri	http://hdl.handle.net/2248/3645
dc.description.abstract	Observations of solar Ca(+) K daily plage area from 1951 to 1977 are analyzed to search for short-period (12-13 day) variations. The 27-day periodicity due to solar rotation modulation is found at all latitudes. Using an autocorrelation technique a 12-13 day periodicity is found only in three of the 57 data sets examined. However, a weak peak around 12-13 days is found in the power spectrum of all of the data sets. It is suggested that two distinct active longitudes separated by about 140-170 degrees are the cause of the 12-13 day periodicity in the autocorrelation.	en
dc.language.iso	en	en
dc.publisher	Indian Academy of Sciences	en
dc.relation.uri	http://ads.iucaa.ernet.in/abs/1989JApA...10..381S	en
dc.subject	Calcium	en
dc.subject	Faculae	en
dc.subject	Power spectra	en
dc.subject	Sunspot cycle	en
dc.subject	Twenty-seven day variation	en
dc.subject	Autocorrelation	en
dc.subject	Fast fourier transformations	en
dc.subject	Solar rotation	en
dc.subject	Spectrum analysis	en
dc.title	Analysis of Ca(+) K plage area for short period variation	en
dc.type	Article	en