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tokens: fluencies (chemical equilibrium). The chemical equilibrium during ice processing by photons, electrons or ions occurs at large fluences when parent and daughter species reach abundances that keep each other's abundance constant during reciprocally production-destruction reactions in the presence of incoming energy. This steady state scenario explains the horizontal plateau in chemical abundances observed at fluences larger than ∼1.4 × 10 13 ion cm −2 (see for example Fig. 4 ). Additionally, in the case of ion bombardment, the sputtering may affect drastically the molecular abundances as function of time, mainly in the beginning when parent species are more affected by sputtering. At high fluences, the molecular abundance reaches the chemical equilibrium, the sputtering affects equally all the species and their column densities decrease (in a constant rate) as function of fluence. The chemical equilibrium is also affected by the sample temperature since volatile products tend to desorb from the ice. More details on chemical equilibrium induced by radiation in ices are given elsewhere (Vasconcelos et al. 2017 ). Studying the radiolysis of N 2 : CO (1:1) ice at 10 K by electron beam irradiation with final energy dose similar to the exposure of astrophysical ice to 5 × 10 6 year in the ISM, Jamieson et al. ( 2005 ) have found the result N 2 O/N 2 > 6.0 × 10 −4 . Bombarding N-rich ices by protons and considering the band strengths in the infrared for N 2 O and N 2 derived by Jamieson et al. ( 2005 ), Loeffler et al. ( 2010 ) have found N 2 O/N 2 ∼ 2.0 × 10 −3 for the equilibrium chemistry attainted at longer fluencies. This value is very similar to the one observed in the gas phase at Sgr B2, as shown above (Womack, Ziurys Wyckoff 1992 ). The current manuscript investigates the survival of solid N 2 O against ionizing field (1.5 MeV N + cosmic ray analogues). From the measured destruction cross-section (σ d ) and the ion flux (Φ) in the laboratory, the photodissociation rate at laboratory (k d = σ d × Φ), turns out to be about 7.0 × 10 −4 ions s −1 . Same equation can be employed to derive the photodissociation rate in space. Considering first order kinetics for the destruction of N 2 O by swift ions, the evolution of N 2 O abundance as a function of time is described by equation ( 25 ) where N(t) and N(t 0 ) represents the molecular abundance at a given time (t) and at the beginning of experiment. κ d is the dissociation rate in units of ions s −1 , σ d is the dissociation cross-section in units of cm 2 and Φ is the ion flux in units of ions cm −2 s −1 . To extrapolate the current laboratory results to astrophysical environments, the flux of medium-mass ions (3 Z 11) having energies between 0.1–10.0 MeV/u estimated by Pilling et al. ( 2013 ) is used. The values considered are 3.0 × 10 −1 and 1.0 × 10 −1 ion cm −2 s −1 , for the ISM and inside the Solar system at Pluto orbit, respectively. Fig. 5 presents the evolution of N 2 O abundance, for ices