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Long-term persistence of solar activityWe examine the question of whether or not the non-periodic variations in solar activity are caused by a white-noise, random process. The Hurst exponent, which characterizes the persistence of a time series, is evaluated for the series of C-14 data for the time interval from about 6000 BC to 1950 AD. We find a constant Hurst exponent, suggesting that solar activity in the frequency range from 100 to 3000 years includes an important continuum component in addition to the well-known periodic variations. The value we calculate, H approximately 0.8, is significantly larger than the value of 0.5 that would correspond to variations produced by a white-noise process. This value is in good agreement with the results for the monthly sunspot data reported elsewhere, indicating that the physics that produces the continuum is a correlated random process and that it is the same type of process over a wide range of time interval lengths.
Document ID
19950031090
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Ruzmaikin, Alexander
(California State University Northridge, CA, United States)
Feynman, Joan
(Jet Propulsion Laboratory, Pasadena, CA United States)
Robinson, Paul
(Jet Propulsion Laboratory, Pasadena, CA United States)
Date Acquired
August 16, 2013
Publication Date
February 1, 1994
Publication Information
Publication: Solar Physics
Volume: 149
Issue: 2
ISSN: 0038-0938
Subject Category
Solar Physics
Accession Number
95A62689
Distribution Limits
Public
Copyright
Other

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