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tokens: images are for the HST bands and for the Spitzer bands. We adopt a -CDM cosmological model with km s Mpc, , and . We assume a Salpeter IMF ( Salpeter 1955 ). All magnitudes are expressed in the AB system ( Oke Gunn 1983 ). 2. Data 2.1. Spectroscopy The available low-resolution (LR, ) and medium-resolution (MR, ) VLT/VIMOS spectroscopy covering the spectral ranges 3400–7000 Å and 4800–10 000 Å were obtained during 2005, with 4hr exposure time for both LR and MR spectra. The LR spectrum continuum sensitivity is at 3700 Å with 4 h and assuming seeing and airmass 1.2. It is calculated over one pixel along dispersion and (full width half maximum) along spatial direction. ( Popesso et al. 2009 ; Balestra et al. 2010 ). Slit widths of were adopted and the median seeing during observations was . We have newly reduced both configurations, in particular focusing on the Lyman continuum emission (LR-spectrum) and the ultraviolet spectral properties in the non-ionizing domain (MR-spectrum). Reduction was done in two ways: as described in Balestra et al. (2010) and the AB–BA method as described in Vanzella et al. (2011 , 2014b) . Both methods produce consistent results. Recently, a near infrared spectrum of Ion2 was obtained with Keck/MOSFIRE in March 2015 (PI: Günther Hasinger). Integration time of 32, 32, and 36 min were obtained in the -, -, and -bands, respectively, with the AB–BA dithering pattern of 2.9. The adopted slit width was 0.7 producing a dispersion of 1.30 Å, 1.63 Å, and 2.17 Å per pixel, in the -, -, and -bands, respectively; the pixels scale along the spatial direction was 0.18/pixel. Ion2 was inserted in a mask aimed to target low- objects as well. The -band is useful for monitoring low- emission lines. Reduction was performed using the standard pipeline 1 . Briefly, two-dimensional sky-subtracted spectra, rectified and wavelength calibrated, are produced from which the one-dimensional variance weighted spectrum is extracted with a top-hat aperture. The wavelength solution was computed from sky emission lines (e.g., Rousselot et al. 2000 ) in the three bands reaching an rms accuracy better than 1/20, 1/30, and 1/40 of the pixel size in -, -, and -bands, respectively (typical rms 0.05 Å). Table 1 Emission line properties. Notes. (a) Observed emission line flux and error corrected for slit losses (50%) in units of erg s cm. In parenthesis, the [O iii ] flux adopting the theoretical ratio ( Storey Zeippen 2000 ). (b) The emission line dust correction method is described in Appendix A . (c) FWHM (instrumental corrected) and error in units of km s. (d) Equivalent width and error in units of Å. (e) Sum of the two components. (f) Main component. (g) Marginal detections (Fig. 6 ): , , and . (h) FWHM is the contribution of the two blended components, 1907–1909 Å. (i) The error is large because the line is on the top of a sky line (Fig. 4 ). Flux calibration was performed by observing the standard star A0V HIP 26577. Given the slit width () and the