| Abstract
| - Aims. We investigate the capability of multistranded loop models subject to nanoflare heating to reproduce the properties recently observed in coronal loops at extreme ultraviolet (EUV) wavelengths. Methods. One-dimensional hydrodynamic simulations of magnetic loop strands were performed with an impulsive, footpoint-localised heating, with a moderate asymmetry between the two loop halves that was produced either by a sequence of identical nanoflares with a given cadence time tC or by a single energy pulse. The temporal evolution of the emission of a multistranded loop was modelled by simply combining the results of independent single-strand simulations, neglecting any spatial interaction among the strands, and was compared with TRACE and SDO/AIA light curves. The density excess with respect to hydrostatic equilibrium (the ψ factor) was evaluated with the filter-ratio technique. Results. Both loop models exhibit a density excess compared with hydrostatic equilibrium models, which agrees well with the observed values (1 ≲ ψ ≲ 12). However, in the single-pulse model the light curve and density excess maxima do not match. On the other hand, the models with a sequence of nanoflares predict strong emission at lower temperatures that cannot be reconciled with the available observations.
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