  We analyze a prominence-like cool plasma structure as observed by Atmospheric
Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). We perform
the Differential Emission Measure (DEM) analysis using various filters of AIA,
and also deduce the temperature and density structure in and around the
observed flux-tube. In addition to deducing plasma parameters, we also find an
evidence of multiple harmonics of fast magnetoacoustic kink waves in the
observed prominence-like magnetic structure. Making use of estimated plasma
parameters and observed wave parameters, under the baseline of MHD seismology,
we deduce magnetic field in the flux-tube. The wave period ratio P1/P2 = 2.18
is also observed in the flux-tube, which carries the signature of magnetic
field divergence where we estimate the tube expansion factor as 1.27. We
discuss constraints in the estimation of plasma and magnetic field properties
in such a structure in the current observational perspective, which may shed
new light on the localized plasma dynamics and heating scenario in the solar
atmosphere.

Solar and Stellar Astrophysics