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Proper orthogonal decomposition of solar photospheric motions

A. Vecchio·V. Carbone·F. Lepreti·L. Primavera·L. Sorriso-Valvo·P. Veltri·G. Alfonsi·Th. Straus
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Abstract

The spatio-temporal dynamics of the solar photosphere is studied by performing a Proper Orthogonal Decomposition (POD) of line of sight velocity fields computed from high resolution data coming from the MDI/SOHO instrument. Using this technique, we are able to identify and characterize the different dynamical regimes acting in the system. Low frequency oscillations, with frequencies in the range 20-130 microHz, dominate the most energetic POD modes (excluding solar rotation), and are characterized by spatial patterns with typical scales of about 3 Mm. Patterns with larger typical scales of 10 Mm, are associated to p-modes oscillations at frequencies of about 3000 microHz.

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A. Vecchio, V. Carbone, F. Lepreti, L. Primavera, L. Sorriso-Valvo, P. Veltri, G. Alfonsi, Th. Straus. 2005-06-27. Proper orthogonal decomposition of solar photospheric motions. https://doi.org/10.1103/physrevlett.95.061102

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