https://doi.org/10.5061/dryad.cnp5hqcdd

Data set of figures of the article.

Description of the data and file structure

Text files (ascii) in table form with the physical units in the first line of the table.

Data fig.1: Spectrum of aliphatic rich pixels compared with an average spectrum of the Ernutet region taken by the VIR spectrometer.

Data in Fig.2 :  Energetic ion irradiation experiments were performed at INAF – Osservatorio Astrofisico di Catania (Italy). Three analogs in the form of compact pellets (named CU-1, CU-2, and CU-3) were irradiated under high vacuum at room temperature by 200 keV He+, N+, and H+ ions respectively. At selected fluences, samples were removed from the irradiation chamber and analised by means of diffuse reflectance IR spectroscopy at room pressure and temperature (see Material and Methods section). The data shows the  decrease of  the 3.4 µm feature of the CU-3 sample as prepared and after irradiation with 200 keV H+ at increasing fluences. 

Data in fig.3  show  the trend of  3.4 µm band area of Ceres’ analog samples as a function of irradiation dose after exposure to 200 keV H+, He+, and N+.  The data reported In Fig. 3A are  the normalised 3.4 µm band area  as a function of the dose for the three samples after irradiation with 200 keV He+, N+, and H+, respectively. 

Data of fig.4 show the estimated  Lifetime of the 3.4 µm band exposed to solar particle irradiation (100 keV – 1 GeV) at Ceres. Lifetime is estimated from OMERE simulations adopting the destruction cross section σ in units of 16u/eV obtained from the experimental data for three different porosity values. Dashed vertical lines show the estimated IR photons penetration depth in laboratory analogues (5 µm) and in the Ceres surface (about 100 µm). 

Data in fig.5 show** **Diffuse reflectance spectra of Ceres simulant sample in the range 3.24-3.68 µm at room temperature acquired during UV irradiation.

Data in fig.6  show  the  transmission spectra of the Ceres’ analog sample after continuum subtraction in the range 3.30-3.60 µm as produced and after hydrogen atom exposure for 3600 s and 18000 s; b)  evolution of the integrated optical depth of the aliphatic C-H modes with H atom exposure time.

Data in fig.7  show  the diffuse reflectance spectrum acquired at room temperature of the Ceres analogue sample. 

Data in fig.8 represent  the Residual fraction CH.  Residual fraction of CH bonds after exposure to SEP radiation as a function of depth for different porosity values (0.0, 0.5, and 0.9) and different irradiation time (0.1, 1, and 5 million years).