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It has been shown recently that magnetic twist and axisymmetric MHD modes areubiquitous in the solar atmosphere and therefore, the study of resonantabsorption for these modes have become a pressing issue as it can haveimportant consequences for heating magnetic flux tubes in the solar atmosphereand the observed damping. In this investigation, for the first time, wecalculate the damping rate for axisymmetric MHD waves in weakly twistedmagnetic flux tubes. Our aim is to investigate the impact of resonant dampingof these modes for solar atmospheric conditions. This analytical study is basedon an idealized configuration of a straight magnetic flux tube with a weakmagnetic twist inside as well as outside the tube. By implementing theconservation laws derived by \cite{Sakurai:1991aa} and the analytic solutionsfor weakly twisted flux tubes obtained recently by \cite{Giagkiozis:2015apj},we derive a dispersion relation for resonantly damped axisymmetric modes in thespectrum of the Alfv\'{e}n continuum. We also obtain an insightful analyticalexpression for the damping rate in the long wavelength limit. Furthermore, itshown that both the longitudinal magnetic field and the density, which areallowed to vary continuously in the inhomogeneous layer, have a significantimpact on the damping time. Given the conditions in the solar atmosphere,resonantly damped axisymmetric modes are highly likely to be ubiquitous andplay an important role in energy dissipation.  We also suggest that given the character of these waves, it is likely thatthey have already been observed in the guise of Alfv\'{e}n waves.

Resonant Absorption of Axisymmetric Modes in Twisted Magnetic Flux Tubes