Abstract:
Longitudinal and transverse oscillations are frequently observed in the solar prominences and
/
or filaments. These oscilla-
tions are excited by a large-scale shock wave, impulsive flares at one leg of the filament threads, or due to any low coronal eruptions.
We report simultaneous longitudinal and transverse oscillations in the filament threads of a quiescent region filament. We observe a
large filament in the northwest of the solar disk on July 6, 2017. On July 7, 2017, it starts rising around 13:00 UT. We then observe a
failed eruption and subsequently the filament threads start to oscillate around 16:00 UT.
Aims.
We analyse oscillations in the threads of a filament and utilize seismology techniques to estimate magnetic field strength and
length of filament threads.
Methods.
We placed horizontal and vertical artificial slits on the filament threads to capture the longitudinal and transverse oscil-
lations of the threads. Data from Atmospheric Imaging Assembly onboard Solar Dynamics Observatory were used to detect the
oscillations.
Results.
We find signatures of large-amplitude longitudinal oscillations (LALOs). We also detect damping in LALOs. In one thread
of the filament, we observe large-amplitude transverse oscillations (LATOs). Using the pendulum model, we estimate the lower limit
of magnetic field strength and radius of curvature from the observed parameter of LALOs.
Conclusions.
We show the co-existence of two di
ff
erent wave modes in the same filament threads. We estimate magnetic field from
LALOs and suggest a possible range of the length of the filament threads using LATOs.
