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Under cold conditions in dense cores, gas-phase molecules and atoms aredepleted from the gas-phase to the surface of interstellar grains. Consideringthe time scales and physical conditions within these cores, a portion of thesemolecules has to be brought back into the gas-phase to explain theirobservation by milimeter telescopes. We tested the respective efficiencies ofthe different mechanisms commonly included in the models. We also tested theaddition of sputtering of ice grain mantles via a collision with cosmic rays inthe electronic stopping power regime. The ice sputtering induced by cosmic rayshas been added to the Nautilus gas-grain model while the other processes werealready present. Each of these processes were tested on a 1D physical structuredetermined by observations in TMC1 cold cores. The resulting 1D chemicalstructure was also compared to methanol gas-phase abundances observed in thesecores. We found that all species are not sensitive in the same way to thenon-thermal desorption mechanisms, and the sensitivity also depends on thephysical conditions. Thus, it is mandatory to include all of them. Chemicaldesorption seems to be essential in reproducing the observations for Hdensities smaller than $4\times 10^4$~cm$^{-3}$, whereas sputtering isessential above this density. The models are, however, systematically below theobserved methanol abundances. A more efficient chemical desorption and a moreefficient sputtering could better reproduce the observations. In conclusion,the sputtering of ices by cosmic-rays collisions may be the most efficientdesorption mechanism at high density (a few $10^4$~cm$^{-3}$ under theconditions studied here) in cold cores, whereas chemical desorption is stillrequired at smaller densities. Additional works are needed on both mechanismsto assess their efficiency with respect to the main ice composition.

Efficiency of non-thermal desorptions in cold-core conditions. Testing the sputtering of grain mantles induced by cosmic rays