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The debate on the oxygen abundances of metal-poor stars has its origin incontradictory results obtained using different abundance indicators. To achievea better understanding of the problem we have acquired high quality spectrawith the Ultraviolet and Visual Echelle Spectrograph at VLT, with asignal-to-noise of the order of 100 in the near ultraviolet and 500 in theoptical and near infrared wavelength range. Three different oxygen abundanceindicators, OH ultraviolet lines around 310.0 nm, the [OI] line at 630.03 nmand the OI lines at 777.1-5 nm were observed in the spectra of 13 metal-poorsubgiants with -3.0<=[Fe/H]<=-1.5. Oxygen abundances were obtained from theanalysis of these indicators which was carried out assuming local thermodynamicequilibrium and plane-parallel model atmospheres. Abundances derived from OIwere corrected for departures from local thermodynamic equilibrium. Stellarparameters were computed using Teff-vs-color calibrations based on the infraredflux method and Balmer line profiles, Hipparcos parallaxes and FeII lines.[O/Fe] values derived from the forbidden line at 630.03 nm are consistent withan oxygen/iron ratio that varies linearly with [Fe/H] as[O/Fe]}=-0.09(+/-0.08)[Fe/H]+0.36(+/-0.15). Values based on the OI triplet areon average 0.19+/-0.22 dex(s.d.) higher than the values based on the forbiddenline while the agreement between OH ultraviolet lines and the forbidden line ismuch better with a mean difference of the order of -0.09+/-0.25 dex(s.d.). Ingeneral, our results follow the same trend as previously published results withthe exception of the ones based on OH ultraviolet lines. In that case ourresults lie below the values which gave rise to the oxygen abundance debate formetal-poor stars.Comment: Accepted for publication in A&

Oxygen abundances in metal-poor subgiants as determined from [O I], O I and OH lines