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Current analytical and numerical modelling suggest the existence ofubiquitous thin current sheets in the corona that could explain the observedheating requirements. On the other hand, new high resolution observations ofthe corona indicate that its magnetic field may tend to organise itself in finestrand-like structures of few hundred kilometres widths. The link between smallstructure in models and the observed widths of strand-like structure severalorders of magnitude larger is still not clear. A popular theoretical scenariois the nanoflare model, in which each strand is the product of an ensemble ofheating events. Here, we suggest an alternative mechanism for strandgeneration. Through forward modelling of 3D MHD simulations we show that smallamplitude transverse MHD waves can lead in a few periods time to strand-likestructure in loops in EUV intensity images. Our model is based on previousnumerical work showing that transverse MHD oscillations can lead toKelvin-Helmholtz instabilities that deform the cross-sectional area of loops.While previous work has focused on large amplitude oscillations, here we showthat the instability can occur even for low wave amplitudes for long and thinloops, matching those presently observed in the corona. We show that thevortices generated from the instability are velocity sheared regions withenhanced emissivity hosting current sheets. Strands result as a complexcombination of the vortices and the line-of-sight angle, last for timescales ofa period and can be observed for spatial resolutions of a tenth of loop radius.

Fine strand-like structure in the solar corona from MHD transverse oscillations