High-frequency oscillations in a solar active region observed with the RAPID DUAL IMAGER


Autoria(s): Jess, D.B.; Andic, A.; Mathioudakis, M.; Bloomfield, D. S.; Keenan, F. P.
Data(s)

01/10/2007

Resumo

High-cadence, synchronized, multiwavelength optical observations of a solar active region (NOAA 10794) are presented. The data were obtained with the Dunn Solar Telescope at the National Solar Observatory/Sacramento Peak using a newly developed camera system: the rapid dual imager. Wavelet analysis is undertaken to search for intensity related oscillatory signatures, and periodicities ranging from 20 to 370 s are found with significance levels exceeding 95%. Observations in the H-α blue wing show more penumbral oscillatory phenomena when compared to simultaneous G-band observations. The H-α oscillations are interpreted as the signatures of plasma motions with a mean velocity of 20 km s-1. The strong oscillatory power over H-α blue-wing and G-band penumbral bright grains is an indication of the Evershed flow with frequencies higher than previously reported.

Identificador

http://pure.qub.ac.uk/portal/en/publications/highfrequency-oscillations-in-a-solar-active-region-observed-with-the-rapid-dual-imager(440f1d10-a371-4e56-a94f-7051e6c8ed54).html

http://dx.doi.org/10.1051/0004-6361:20077142

Idioma(s)

eng

Direitos

info:eu-repo/semantics/restrictedAccess

Fonte

Jess , D B , Andic , A , Mathioudakis , M , Bloomfield , D S & Keenan , F P 2007 , ' High-frequency oscillations in a solar active region observed with the RAPID DUAL IMAGER ' Astronomy and Astrophysics , vol 473 , pp. 943-950 . DOI: 10.1051/0004-6361:20077142

Palavras-Chave #instrumentation: miscellaneous #waves #Sun: chromosphere #Sun: oscillations #Sun: photosphere #Sun: sunspots #/dk/atira/pure/subjectarea/asjc/1900/1912 #Space and Planetary Science
Tipo

article