SIMBAD references

We report on detailed Monte Carlo inversion analysis of five OVI systems from the spectrum of the bright quasar HE 0515-4414 (z_em=1.71). The associated system at z_abs=1.697 with the neutral hydrogen column density N(HI)=4.4x10¹³ cm^–2 shows pronounced absorption from highly ionized transitions of CIII, CIV, NV, OVI, SiIV, and probably SVI. We found that only a power law type ionizing spectrum (J_ν∝ν^–1.5) is consistent with the observed sample of the line profiles, i.e. the system is definitely intrinsic. The relative metal abundances give almost the solar pattern and the metallicity of ∼5 times solar. The system originates in a thin shell of the line-of-sight thickness L≲16pc. Two OVI systems at z_abs=1.674 ([C/H]≃-1.6) and 1.602 ([O/H]≃-1.1), arising in intervening halos, have linear sizes of L≃3-14kpc and ≃17kpc, respectively. Absorption systems at z_abs=1.385 ([C/H]≃-0.3, L≃1.7-2.5kpc) and z_abs=1.667 ([C/H]≃-0.5, L≃1kpc) exhibit characteristics very similar to that observed in metal-enriched high velocity clouds in the Milky Way. These systems are probably embedded in extremely metal-poor halos with [C/H]←2.4 (z_abs=1.667) and [C/H]←3.7 (z_abs=1.385). We also found two additional extremely metal-poor Lyα systems at z_abs=1.500 and 1.681 with, respectively, N(HI)≃1.7x10¹⁵ and 1.8x10¹⁵cm^–2 and [C/H]←4.0 and ←3.0, - an indication that the distribution of metals in the metagalactic medium is utterly patchy. Our results show that the ionization states in the analyzed OVI absorbers, ranging from z≃1.4 to 1.7, can be maintained by photoionization only and that the fraction of the shock-heated hot gas with temperature T_kin>10⁵K is negligible in these systems.