Signatures of Cross-sectional Width Modulation in Solar Spicules due to Field-aligned Flows

Authors Organisations
  • Fionnlagh MacKenzie Dover(Author)
    The University of Sheffield
  • Rahul Sharma(Author)
    Universidad de Alcalá
  • Marianna B. Korsós(Author)
    Eötvös L. University
    Hungarian Solar Physics Foundation (HSPF)
  • Robertus Erdélyi(Author)
    The University of Sheffield
    Eötvös L. University
    Hungarian Solar Physics Foundation (HSPF)
Type Article
Original languageEnglish
Article number72
Number of pages9
JournalAstrophysical Journal
Issue number1
Publication statusPublished - 15 Dec 2020
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We report the first observational detection of frequency modulation in the cross-sectional width of spicule structures due to field-aligned plasma flows. Cross-sectional width variations were estimated for the least superimposed off-limb spicules observed in high-resolution Hα imaging spectroscopy data. Analysis of estimated cross-sectional widths suggest periodic oscillations, concurrent with 2D numerical modeling for a jet structure in a stratified solar atmosphere. Spectral analysis for both observed and simulated cross-sectional widths indicate frequency modulation as noticeable shifts in estimated periodicities during rise and fall phases of field-aligned plasma flows in the jet structure. Furthermore, the presence of the first overtone in a dynamic/spicular waveguide is also evident in both the observed and the simulated jet structures. These harmonics can be an important tool for future chromospheric magnetoseismology investigations and applications to dynamic waveguides (like spicules).