J/A+A/530/A50ivo://CDS.VizieR/J/A+A/530/A50doi:10.26093/cds/vizier.35300050CDSParis I.Petitjean P.Rollinde E.Aubourg E.Busca N.Charlassier R.,Delubac T.Hamilton J.-C.Le Goff J.-M.Palanque-Delabrouille N.,Peirani S.Pichon C.Rich J.Vargas-Magana M.Yeche C.2011-07-15T15:27:10Z2011-05-06T09:24:08ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frastronomical-modelsspectroscopyultraviolet-astronomyquasarsFrom a principal component analysis (PCA) of 78 z~3 high-quality quasar spectra in the SDSS-DR7 we derive the principal components that characterize the QSO continuum over the full available wavelength range. The shape of the mean continuum is similar to that measured at low-z (z~1), but the equivalent width of the emission lines is larger at low redshift. We calculate the correlation between fluxes at different wavelengths and find that the emission line fluxes in the red part of the spectrum are correlated with those in the blue part. We construct a projection matrix to predict the continuum in the Lyman{alpha} forest from the red part of the spectrum.2011A&A...530A..50Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/530/A50CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/530/A50https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/530/A50http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/530/A50https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/530/A50https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/530/A50http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/530/A50GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapUVdefaultJ/A+A/530/A50/xiPrincipal Components over the full wavelengthrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlambdaRestframe wavelength in Angstroms0.1nmem.wlfloatFluxMean Continuum normalized near 1280{AA}phot.flux;arith.ratiodoublexi11st Principal Component {xi}_1_stat.fit.paramdoublexi22nd Principal Component {xi}_2_stat.fit.paramdoublexi33rd Principal Component {xi}_3_stat.fit.paramdoublexi44th Principal Component {xi}_4_stat.fit.paramdoublexi55th Principal Component {xi}_5_stat.fit.paramdoublexi66th Principal Component {xi}_6_stat.fit.paramdoublexi77th Principal Component {xi}_7_stat.fit.paramdoublexi88th Principal Component {xi}_8_stat.fit.paramdoublexi99th Principal Component {xi}_9_stat.fit.paramdoublexi1010th Principal Component {xi}_10_stat.fit.paramdoubleJ/A+A/530/A50/zetaPrincipal Components redwards to Ly-alpha emissionFluxMean Continuum normalized near 1280{AA}phot.flux;arith.ratiodoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWaveRestframe wavelength in Angstroms0.1nmem.wlfloatzeta11st Principal Component {zeta}_1_stat.fit.paramdoublezeta22nd Principal Component {zeta}_2_stat.fit.paramdoublezeta33rd Principal Component {zeta}_3_stat.fit.paramdoublezeta44th Principal Component {zeta}_4_stat.fit.paramdoublezeta55th Principal Component {zeta}_5_stat.fit.paramdoublezeta66th Principal Component {zeta}_6_stat.fit.paramdoublezeta77th Principal Component {zeta}_7_stat.fit.paramdoublezeta88th Principal Component {zeta}_8_stat.fit.paramdoublezeta99th Principal Component {zeta}_9_stat.fit.paramdoublezeta1010th Principal Component {zeta}_10_stat.fit.paramdoubleJ/A+A/530/A50/projProjection matrixrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintXi11st column of projection matrixstat.fit.paramdoubleXi22nd column of projection matrixstat.fit.paramdoubleXi33rd column of projection matrixstat.fit.paramdoubleXi44th column of projection matrixstat.fit.paramdoubleXi55th column of projection matrixstat.fit.paramdoubleXi66th column of projection matrixstat.fit.paramdoubleXi77th column of projection matrixstat.fit.paramdoubleXi88th column of projection matrixstat.fit.paramdoubleXi99th column of projection matrixstat.fit.paramdoubleXi1010th column of projection matrixstat.fit.paramdouble