Oscillations on Width and Intensity of Slender Ca II H Fibrils from Sunrise/SuFI

DOI: 
10.3847/1538-4365/229/1/7
Publication date: 
17/04/2017
Main author: 
Gafeira R.
IAA authors: 
Del Toro Iniesta, J.C.;Suárez, D.O.
Authors: 
Gafeira R., Jafarzadeh S., Solanki S.K., Lagg A., Van Noort M., Barthol P., Rodríguez J.B., Del Toro Iniesta J.C., Gandorfer A., Gizon L., Hirzberger J., Knölker M., Suárez D.O., Riethmüller T.L., Schmidt W.
Journal: 
Astrophysical Journal, Supplement Series
Publication type: 
Article
Volume: 
229
Number: 
7
Abstract: 
We report the detection of oscillations in slender Ca ii H fibrils (SCFs) from high-resolution observations acquired with the Sunrise balloon-borne solar observatory. The SCFs show obvious oscillations in their intensity, but also their width. The oscillatory behaviors are investigated at several positions along the axes of the SCFs. A large majority of fibrils show signs of oscillations in intensity. Their periods and phase speeds are analyzed using a wavelet analysis. The width and intensity perturbations have overlapping distributions of the wave period. The obtained distributions have median values of the period of 32 ±17 s and 36 ±25 s, respectively. We find that the fluctuations of both parameters propagate in the SCFs with speeds of km s-1 and km s-1, respectively. Furthermore, the width and intensity oscillations have a strong tendency to be either in anti-phase or, to a smaller extent, in phase. This suggests that the oscillations of both parameters are caused by the same wave mode and that the waves are likely propagating. Taking all the evidence together, the most likely wave mode to explain all measurements and criteria is the fast sausage mode. © 2017. The American Astronomical Society. All rights reserved..
Database: 
SCOPUS
ADS
URL: 
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85016160508&doi=10.3847%2f1538-4365%2f229%2f1%2f7&partnerID=40&md5=7f26b586201d5df35cdbc3c671e11c6b
ADS Bibcode: 
2017ApJS..229....7G
Keywords: 
Sun: chromosphere; Sun: magnetic fields; Sun: oscillations; techniques: imaging spectroscopy